1// SPDX-License-Identifier: GPL-2.0
2/*
3 * trace_events_hist - trace event hist triggers
4 *
5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
6 */
7
8#include <linux/module.h>
9#include <linux/kallsyms.h>
10#include <linux/security.h>
11#include <linux/mutex.h>
12#include <linux/slab.h>
13#include <linux/stacktrace.h>
14#include <linux/rculist.h>
15#include <linux/tracefs.h>
16
17/* for gfp flag names */
18#include <linux/trace_events.h>
19#include <trace/events/mmflags.h>
20
21#include "tracing_map.h"
22#include "trace_synth.h"
23
24#define ERRORS \
25 C(NONE, "No error"), \
26 C(DUPLICATE_VAR, "Variable already defined"), \
27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \
28 C(TOO_MANY_VARS, "Too many variables defined"), \
29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \
30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \
31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \
32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \
33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \
34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \
35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \
36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \
37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \
38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \
39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \
40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \
41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \
42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \
43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \
44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \
45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \
46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \
47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \
48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \
49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \
50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \
51 C(TOO_MANY_PARAMS, "Too many action params"), \
52 C(PARAM_NOT_FOUND, "Couldn't find param"), \
53 C(INVALID_PARAM, "Invalid action param"), \
54 C(ACTION_NOT_FOUND, "No action found"), \
55 C(NO_SAVE_PARAMS, "No params found for save()"), \
56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \
57 C(ACTION_MISMATCH, "Handler doesn't support action"), \
58 C(NO_CLOSING_PAREN, "No closing paren found"), \
59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \
60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \
61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \
62 C(VAR_NOT_FOUND, "Couldn't find variable"), \
63 C(FIELD_NOT_FOUND, "Couldn't find field"), \
64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \
65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \
66 C(EMPTY_SORT_FIELD, "Empty sort field"), \
67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \
68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \
69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \
70 C(EXPECT_NUMBER, "Expecting numeric literal"), \
71 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \
72 C(DIVISION_BY_ZERO, "Division by zero"), \
73 C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"),
74
75#undef C
76#define C(a, b) HIST_ERR_##a
77
78enum { ERRORS };
79
80#undef C
81#define C(a, b) b
82
83static const char *err_text[] = { ERRORS };
84
85struct hist_field;
86
87typedef u64 (*hist_field_fn_t) (struct hist_field *field,
88 struct tracing_map_elt *elt,
89 struct trace_buffer *buffer,
90 struct ring_buffer_event *rbe,
91 void *event);
92
93#define HIST_FIELD_OPERANDS_MAX 2
94#define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
95#define HIST_ACTIONS_MAX 8
96#define HIST_CONST_DIGITS_MAX 21
97#define HIST_DIV_SHIFT 20 /* For optimizing division by constants */
98
99enum field_op_id {
100 FIELD_OP_NONE,
101 FIELD_OP_PLUS,
102 FIELD_OP_MINUS,
103 FIELD_OP_UNARY_MINUS,
104 FIELD_OP_DIV,
105 FIELD_OP_MULT,
106};
107
108enum hist_field_fn {
109 HIST_FIELD_FN_NOP,
110 HIST_FIELD_FN_VAR_REF,
111 HIST_FIELD_FN_COUNTER,
112 HIST_FIELD_FN_CONST,
113 HIST_FIELD_FN_LOG2,
114 HIST_FIELD_FN_BUCKET,
115 HIST_FIELD_FN_TIMESTAMP,
116 HIST_FIELD_FN_CPU,
117 HIST_FIELD_FN_STRING,
118 HIST_FIELD_FN_DYNSTRING,
119 HIST_FIELD_FN_RELDYNSTRING,
120 HIST_FIELD_FN_PSTRING,
121 HIST_FIELD_FN_S64,
122 HIST_FIELD_FN_U64,
123 HIST_FIELD_FN_S32,
124 HIST_FIELD_FN_U32,
125 HIST_FIELD_FN_S16,
126 HIST_FIELD_FN_U16,
127 HIST_FIELD_FN_S8,
128 HIST_FIELD_FN_U8,
129 HIST_FIELD_FN_UMINUS,
130 HIST_FIELD_FN_MINUS,
131 HIST_FIELD_FN_PLUS,
132 HIST_FIELD_FN_DIV,
133 HIST_FIELD_FN_MULT,
134 HIST_FIELD_FN_DIV_POWER2,
135 HIST_FIELD_FN_DIV_NOT_POWER2,
136 HIST_FIELD_FN_DIV_MULT_SHIFT,
137 HIST_FIELD_FN_EXECNAME,
138 HIST_FIELD_FN_STACK,
139};
140
141/*
142 * A hist_var (histogram variable) contains variable information for
143 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF
144 * flag set. A hist_var has a variable name e.g. ts0, and is
145 * associated with a given histogram trigger, as specified by
146 * hist_data. The hist_var idx is the unique index assigned to the
147 * variable by the hist trigger's tracing_map. The idx is what is
148 * used to set a variable's value and, by a variable reference, to
149 * retrieve it.
150 */
151struct hist_var {
152 char *name;
153 struct hist_trigger_data *hist_data;
154 unsigned int idx;
155};
156
157struct hist_field {
158 struct ftrace_event_field *field;
159 unsigned long flags;
160 unsigned long buckets;
161 const char *type;
162 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
163 struct hist_trigger_data *hist_data;
164 enum hist_field_fn fn_num;
165 unsigned int ref;
166 unsigned int size;
167 unsigned int offset;
168 unsigned int is_signed;
169
170 /*
171 * Variable fields contain variable-specific info in var.
172 */
173 struct hist_var var;
174 enum field_op_id operator;
175 char *system;
176 char *event_name;
177
178 /*
179 * The name field is used for EXPR and VAR_REF fields. VAR
180 * fields contain the variable name in var.name.
181 */
182 char *name;
183
184 /*
185 * When a histogram trigger is hit, if it has any references
186 * to variables, the values of those variables are collected
187 * into a var_ref_vals array by resolve_var_refs(). The
188 * current value of each variable is read from the tracing_map
189 * using the hist field's hist_var.idx and entered into the
190 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx].
191 */
192 unsigned int var_ref_idx;
193 bool read_once;
194
195 unsigned int var_str_idx;
196
197 /* Numeric literals are represented as u64 */
198 u64 constant;
199 /* Used to optimize division by constants */
200 u64 div_multiplier;
201};
202
203static u64 hist_fn_call(struct hist_field *hist_field,
204 struct tracing_map_elt *elt,
205 struct trace_buffer *buffer,
206 struct ring_buffer_event *rbe,
207 void *event);
208
209static u64 hist_field_const(struct hist_field *field,
210 struct tracing_map_elt *elt,
211 struct trace_buffer *buffer,
212 struct ring_buffer_event *rbe,
213 void *event)
214{
215 return field->constant;
216}
217
218static u64 hist_field_counter(struct hist_field *field,
219 struct tracing_map_elt *elt,
220 struct trace_buffer *buffer,
221 struct ring_buffer_event *rbe,
222 void *event)
223{
224 return 1;
225}
226
227static u64 hist_field_string(struct hist_field *hist_field,
228 struct tracing_map_elt *elt,
229 struct trace_buffer *buffer,
230 struct ring_buffer_event *rbe,
231 void *event)
232{
233 char *addr = (char *)(event + hist_field->field->offset);
234
235 return (u64)(unsigned long)addr;
236}
237
238static u64 hist_field_dynstring(struct hist_field *hist_field,
239 struct tracing_map_elt *elt,
240 struct trace_buffer *buffer,
241 struct ring_buffer_event *rbe,
242 void *event)
243{
244 u32 str_item = *(u32 *)(event + hist_field->field->offset);
245 int str_loc = str_item & 0xffff;
246 char *addr = (char *)(event + str_loc);
247
248 return (u64)(unsigned long)addr;
249}
250
251static u64 hist_field_reldynstring(struct hist_field *hist_field,
252 struct tracing_map_elt *elt,
253 struct trace_buffer *buffer,
254 struct ring_buffer_event *rbe,
255 void *event)
256{
257 u32 *item = event + hist_field->field->offset;
258 u32 str_item = *item;
259 int str_loc = str_item & 0xffff;
260 char *addr = (char *)&item[1] + str_loc;
261
262 return (u64)(unsigned long)addr;
263}
264
265static u64 hist_field_pstring(struct hist_field *hist_field,
266 struct tracing_map_elt *elt,
267 struct trace_buffer *buffer,
268 struct ring_buffer_event *rbe,
269 void *event)
270{
271 char **addr = (char **)(event + hist_field->field->offset);
272
273 return (u64)(unsigned long)*addr;
274}
275
276static u64 hist_field_log2(struct hist_field *hist_field,
277 struct tracing_map_elt *elt,
278 struct trace_buffer *buffer,
279 struct ring_buffer_event *rbe,
280 void *event)
281{
282 struct hist_field *operand = hist_field->operands[0];
283
284 u64 val = hist_fn_call(hist_field: operand, elt, buffer, rbe, event);
285
286 return (u64) ilog2(roundup_pow_of_two(val));
287}
288
289static u64 hist_field_bucket(struct hist_field *hist_field,
290 struct tracing_map_elt *elt,
291 struct trace_buffer *buffer,
292 struct ring_buffer_event *rbe,
293 void *event)
294{
295 struct hist_field *operand = hist_field->operands[0];
296 unsigned long buckets = hist_field->buckets;
297
298 u64 val = hist_fn_call(hist_field: operand, elt, buffer, rbe, event);
299
300 if (WARN_ON_ONCE(!buckets))
301 return val;
302
303 if (val >= LONG_MAX)
304 val = div64_ul(val, buckets);
305 else
306 val = (u64)((unsigned long)val / buckets);
307 return val * buckets;
308}
309
310static u64 hist_field_plus(struct hist_field *hist_field,
311 struct tracing_map_elt *elt,
312 struct trace_buffer *buffer,
313 struct ring_buffer_event *rbe,
314 void *event)
315{
316 struct hist_field *operand1 = hist_field->operands[0];
317 struct hist_field *operand2 = hist_field->operands[1];
318
319 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
320 u64 val2 = hist_fn_call(hist_field: operand2, elt, buffer, rbe, event);
321
322 return val1 + val2;
323}
324
325static u64 hist_field_minus(struct hist_field *hist_field,
326 struct tracing_map_elt *elt,
327 struct trace_buffer *buffer,
328 struct ring_buffer_event *rbe,
329 void *event)
330{
331 struct hist_field *operand1 = hist_field->operands[0];
332 struct hist_field *operand2 = hist_field->operands[1];
333
334 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
335 u64 val2 = hist_fn_call(hist_field: operand2, elt, buffer, rbe, event);
336
337 return val1 - val2;
338}
339
340static u64 hist_field_div(struct hist_field *hist_field,
341 struct tracing_map_elt *elt,
342 struct trace_buffer *buffer,
343 struct ring_buffer_event *rbe,
344 void *event)
345{
346 struct hist_field *operand1 = hist_field->operands[0];
347 struct hist_field *operand2 = hist_field->operands[1];
348
349 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
350 u64 val2 = hist_fn_call(hist_field: operand2, elt, buffer, rbe, event);
351
352 /* Return -1 for the undefined case */
353 if (!val2)
354 return -1;
355
356 /* Use shift if the divisor is a power of 2 */
357 if (!(val2 & (val2 - 1)))
358 return val1 >> __ffs64(word: val2);
359
360 return div64_u64(dividend: val1, divisor: val2);
361}
362
363static u64 div_by_power_of_two(struct hist_field *hist_field,
364 struct tracing_map_elt *elt,
365 struct trace_buffer *buffer,
366 struct ring_buffer_event *rbe,
367 void *event)
368{
369 struct hist_field *operand1 = hist_field->operands[0];
370 struct hist_field *operand2 = hist_field->operands[1];
371
372 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
373
374 return val1 >> __ffs64(word: operand2->constant);
375}
376
377static u64 div_by_not_power_of_two(struct hist_field *hist_field,
378 struct tracing_map_elt *elt,
379 struct trace_buffer *buffer,
380 struct ring_buffer_event *rbe,
381 void *event)
382{
383 struct hist_field *operand1 = hist_field->operands[0];
384 struct hist_field *operand2 = hist_field->operands[1];
385
386 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
387
388 return div64_u64(dividend: val1, divisor: operand2->constant);
389}
390
391static u64 div_by_mult_and_shift(struct hist_field *hist_field,
392 struct tracing_map_elt *elt,
393 struct trace_buffer *buffer,
394 struct ring_buffer_event *rbe,
395 void *event)
396{
397 struct hist_field *operand1 = hist_field->operands[0];
398 struct hist_field *operand2 = hist_field->operands[1];
399
400 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
401
402 /*
403 * If the divisor is a constant, do a multiplication and shift instead.
404 *
405 * Choose Z = some power of 2. If Y <= Z, then:
406 * X / Y = (X * (Z / Y)) / Z
407 *
408 * (Z / Y) is a constant (mult) which is calculated at parse time, so:
409 * X / Y = (X * mult) / Z
410 *
411 * The division by Z can be replaced by a shift since Z is a power of 2:
412 * X / Y = (X * mult) >> HIST_DIV_SHIFT
413 *
414 * As long, as X < Z the results will not be off by more than 1.
415 */
416 if (val1 < (1 << HIST_DIV_SHIFT)) {
417 u64 mult = operand2->div_multiplier;
418
419 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT;
420 }
421
422 return div64_u64(dividend: val1, divisor: operand2->constant);
423}
424
425static u64 hist_field_mult(struct hist_field *hist_field,
426 struct tracing_map_elt *elt,
427 struct trace_buffer *buffer,
428 struct ring_buffer_event *rbe,
429 void *event)
430{
431 struct hist_field *operand1 = hist_field->operands[0];
432 struct hist_field *operand2 = hist_field->operands[1];
433
434 u64 val1 = hist_fn_call(hist_field: operand1, elt, buffer, rbe, event);
435 u64 val2 = hist_fn_call(hist_field: operand2, elt, buffer, rbe, event);
436
437 return val1 * val2;
438}
439
440static u64 hist_field_unary_minus(struct hist_field *hist_field,
441 struct tracing_map_elt *elt,
442 struct trace_buffer *buffer,
443 struct ring_buffer_event *rbe,
444 void *event)
445{
446 struct hist_field *operand = hist_field->operands[0];
447
448 s64 sval = (s64)hist_fn_call(hist_field: operand, elt, buffer, rbe, event);
449 u64 val = (u64)-sval;
450
451 return val;
452}
453
454#define DEFINE_HIST_FIELD_FN(type) \
455 static u64 hist_field_##type(struct hist_field *hist_field, \
456 struct tracing_map_elt *elt, \
457 struct trace_buffer *buffer, \
458 struct ring_buffer_event *rbe, \
459 void *event) \
460{ \
461 type *addr = (type *)(event + hist_field->field->offset); \
462 \
463 return (u64)(unsigned long)*addr; \
464}
465
466DEFINE_HIST_FIELD_FN(s64);
467DEFINE_HIST_FIELD_FN(u64);
468DEFINE_HIST_FIELD_FN(s32);
469DEFINE_HIST_FIELD_FN(u32);
470DEFINE_HIST_FIELD_FN(s16);
471DEFINE_HIST_FIELD_FN(u16);
472DEFINE_HIST_FIELD_FN(s8);
473DEFINE_HIST_FIELD_FN(u8);
474
475#define for_each_hist_field(i, hist_data) \
476 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
477
478#define for_each_hist_val_field(i, hist_data) \
479 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
480
481#define for_each_hist_key_field(i, hist_data) \
482 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
483
484#define HITCOUNT_IDX 0
485#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
486
487enum hist_field_flags {
488 HIST_FIELD_FL_HITCOUNT = 1 << 0,
489 HIST_FIELD_FL_KEY = 1 << 1,
490 HIST_FIELD_FL_STRING = 1 << 2,
491 HIST_FIELD_FL_HEX = 1 << 3,
492 HIST_FIELD_FL_SYM = 1 << 4,
493 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
494 HIST_FIELD_FL_EXECNAME = 1 << 6,
495 HIST_FIELD_FL_SYSCALL = 1 << 7,
496 HIST_FIELD_FL_STACKTRACE = 1 << 8,
497 HIST_FIELD_FL_LOG2 = 1 << 9,
498 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
499 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
500 HIST_FIELD_FL_VAR = 1 << 12,
501 HIST_FIELD_FL_EXPR = 1 << 13,
502 HIST_FIELD_FL_VAR_REF = 1 << 14,
503 HIST_FIELD_FL_CPU = 1 << 15,
504 HIST_FIELD_FL_ALIAS = 1 << 16,
505 HIST_FIELD_FL_BUCKET = 1 << 17,
506 HIST_FIELD_FL_CONST = 1 << 18,
507 HIST_FIELD_FL_PERCENT = 1 << 19,
508 HIST_FIELD_FL_GRAPH = 1 << 20,
509};
510
511struct var_defs {
512 unsigned int n_vars;
513 char *name[TRACING_MAP_VARS_MAX];
514 char *expr[TRACING_MAP_VARS_MAX];
515};
516
517struct hist_trigger_attrs {
518 char *keys_str;
519 char *vals_str;
520 char *sort_key_str;
521 char *name;
522 char *clock;
523 bool pause;
524 bool cont;
525 bool clear;
526 bool ts_in_usecs;
527 bool no_hitcount;
528 unsigned int map_bits;
529
530 char *assignment_str[TRACING_MAP_VARS_MAX];
531 unsigned int n_assignments;
532
533 char *action_str[HIST_ACTIONS_MAX];
534 unsigned int n_actions;
535
536 struct var_defs var_defs;
537};
538
539struct field_var {
540 struct hist_field *var;
541 struct hist_field *val;
542};
543
544struct field_var_hist {
545 struct hist_trigger_data *hist_data;
546 char *cmd;
547};
548
549struct hist_trigger_data {
550 struct hist_field *fields[HIST_FIELDS_MAX];
551 unsigned int n_vals;
552 unsigned int n_keys;
553 unsigned int n_fields;
554 unsigned int n_vars;
555 unsigned int n_var_str;
556 unsigned int key_size;
557 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
558 unsigned int n_sort_keys;
559 struct trace_event_file *event_file;
560 struct hist_trigger_attrs *attrs;
561 struct tracing_map *map;
562 bool enable_timestamps;
563 bool remove;
564 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
565 unsigned int n_var_refs;
566
567 struct action_data *actions[HIST_ACTIONS_MAX];
568 unsigned int n_actions;
569
570 struct field_var *field_vars[SYNTH_FIELDS_MAX];
571 unsigned int n_field_vars;
572 unsigned int n_field_var_str;
573 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
574 unsigned int n_field_var_hists;
575
576 struct field_var *save_vars[SYNTH_FIELDS_MAX];
577 unsigned int n_save_vars;
578 unsigned int n_save_var_str;
579};
580
581struct action_data;
582
583typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
584 struct tracing_map_elt *elt,
585 struct trace_buffer *buffer, void *rec,
586 struct ring_buffer_event *rbe, void *key,
587 struct action_data *data, u64 *var_ref_vals);
588
589typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val);
590
591enum handler_id {
592 HANDLER_ONMATCH = 1,
593 HANDLER_ONMAX,
594 HANDLER_ONCHANGE,
595};
596
597enum action_id {
598 ACTION_SAVE = 1,
599 ACTION_TRACE,
600 ACTION_SNAPSHOT,
601};
602
603struct action_data {
604 enum handler_id handler;
605 enum action_id action;
606 char *action_name;
607 action_fn_t fn;
608
609 unsigned int n_params;
610 char *params[SYNTH_FIELDS_MAX];
611
612 /*
613 * When a histogram trigger is hit, the values of any
614 * references to variables, including variables being passed
615 * as parameters to synthetic events, are collected into a
616 * var_ref_vals array. This var_ref_idx array is an array of
617 * indices into the var_ref_vals array, one for each synthetic
618 * event param, and is passed to the synthetic event
619 * invocation.
620 */
621 unsigned int var_ref_idx[SYNTH_FIELDS_MAX];
622 struct synth_event *synth_event;
623 bool use_trace_keyword;
624 char *synth_event_name;
625
626 union {
627 struct {
628 char *event;
629 char *event_system;
630 } match_data;
631
632 struct {
633 /*
634 * var_str contains the $-unstripped variable
635 * name referenced by var_ref, and used when
636 * printing the action. Because var_ref
637 * creation is deferred to create_actions(),
638 * we need a per-action way to save it until
639 * then, thus var_str.
640 */
641 char *var_str;
642
643 /*
644 * var_ref refers to the variable being
645 * tracked e.g onmax($var).
646 */
647 struct hist_field *var_ref;
648
649 /*
650 * track_var contains the 'invisible' tracking
651 * variable created to keep the current
652 * e.g. max value.
653 */
654 struct hist_field *track_var;
655
656 check_track_val_fn_t check_val;
657 action_fn_t save_data;
658 } track_data;
659 };
660};
661
662struct track_data {
663 u64 track_val;
664 bool updated;
665
666 unsigned int key_len;
667 void *key;
668 struct tracing_map_elt elt;
669
670 struct action_data *action_data;
671 struct hist_trigger_data *hist_data;
672};
673
674struct hist_elt_data {
675 char *comm;
676 u64 *var_ref_vals;
677 char **field_var_str;
678 int n_field_var_str;
679};
680
681struct snapshot_context {
682 struct tracing_map_elt *elt;
683 void *key;
684};
685
686/*
687 * Returns the specific division function to use if the divisor
688 * is constant. This avoids extra branches when the trigger is hit.
689 */
690static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor)
691{
692 u64 div = divisor->constant;
693
694 if (!(div & (div - 1)))
695 return HIST_FIELD_FN_DIV_POWER2;
696
697 /* If the divisor is too large, do a regular division */
698 if (div > (1 << HIST_DIV_SHIFT))
699 return HIST_FIELD_FN_DIV_NOT_POWER2;
700
701 divisor->div_multiplier = div64_u64(dividend: (u64)(1 << HIST_DIV_SHIFT), divisor: div);
702 return HIST_FIELD_FN_DIV_MULT_SHIFT;
703}
704
705static void track_data_free(struct track_data *track_data)
706{
707 struct hist_elt_data *elt_data;
708
709 if (!track_data)
710 return;
711
712 kfree(objp: track_data->key);
713
714 elt_data = track_data->elt.private_data;
715 if (elt_data) {
716 kfree(objp: elt_data->comm);
717 kfree(objp: elt_data);
718 }
719
720 kfree(objp: track_data);
721}
722
723static struct track_data *track_data_alloc(unsigned int key_len,
724 struct action_data *action_data,
725 struct hist_trigger_data *hist_data)
726{
727 struct track_data *data = kzalloc(size: sizeof(*data), GFP_KERNEL);
728 struct hist_elt_data *elt_data;
729
730 if (!data)
731 return ERR_PTR(error: -ENOMEM);
732
733 data->key = kzalloc(size: key_len, GFP_KERNEL);
734 if (!data->key) {
735 track_data_free(track_data: data);
736 return ERR_PTR(error: -ENOMEM);
737 }
738
739 data->key_len = key_len;
740 data->action_data = action_data;
741 data->hist_data = hist_data;
742
743 elt_data = kzalloc(size: sizeof(*elt_data), GFP_KERNEL);
744 if (!elt_data) {
745 track_data_free(track_data: data);
746 return ERR_PTR(error: -ENOMEM);
747 }
748
749 data->elt.private_data = elt_data;
750
751 elt_data->comm = kzalloc(size: TASK_COMM_LEN, GFP_KERNEL);
752 if (!elt_data->comm) {
753 track_data_free(track_data: data);
754 return ERR_PTR(error: -ENOMEM);
755 }
756
757 return data;
758}
759
760#define HIST_PREFIX "hist:"
761
762static char *last_cmd;
763static char last_cmd_loc[MAX_FILTER_STR_VAL];
764
765static int errpos(char *str)
766{
767 if (!str || !last_cmd)
768 return 0;
769
770 return err_pos(cmd: last_cmd, str);
771}
772
773static void last_cmd_set(struct trace_event_file *file, char *str)
774{
775 const char *system = NULL, *name = NULL;
776 struct trace_event_call *call;
777
778 if (!str)
779 return;
780
781 kfree(objp: last_cmd);
782
783 last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str);
784 if (!last_cmd)
785 return;
786
787 if (file) {
788 call = file->event_call;
789 system = call->class->system;
790 if (system) {
791 name = trace_event_name(call);
792 if (!name)
793 system = NULL;
794 }
795 }
796
797 if (system)
798 snprintf(buf: last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name);
799}
800
801static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos)
802{
803 if (!last_cmd)
804 return;
805
806 tracing_log_err(tr, loc: last_cmd_loc, cmd: last_cmd, errs: err_text,
807 type: err_type, pos: err_pos);
808}
809
810static void hist_err_clear(void)
811{
812 if (last_cmd)
813 last_cmd[0] = '\0';
814 last_cmd_loc[0] = '\0';
815}
816
817typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
818 unsigned int *var_ref_idx);
819
820static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
821 unsigned int *var_ref_idx)
822{
823 struct tracepoint *tp = event->tp;
824
825 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
826 struct tracepoint_func *probe_func_ptr;
827 synth_probe_func_t probe_func;
828 void *__data;
829
830 if (!(cpu_online(raw_smp_processor_id())))
831 return;
832
833 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
834 if (probe_func_ptr) {
835 do {
836 probe_func = probe_func_ptr->func;
837 __data = probe_func_ptr->data;
838 probe_func(__data, var_ref_vals, var_ref_idx);
839 } while ((++probe_func_ptr)->func);
840 }
841 }
842}
843
844static void action_trace(struct hist_trigger_data *hist_data,
845 struct tracing_map_elt *elt,
846 struct trace_buffer *buffer, void *rec,
847 struct ring_buffer_event *rbe, void *key,
848 struct action_data *data, u64 *var_ref_vals)
849{
850 struct synth_event *event = data->synth_event;
851
852 trace_synth(event, var_ref_vals, var_ref_idx: data->var_ref_idx);
853}
854
855struct hist_var_data {
856 struct list_head list;
857 struct hist_trigger_data *hist_data;
858};
859
860static u64 hist_field_timestamp(struct hist_field *hist_field,
861 struct tracing_map_elt *elt,
862 struct trace_buffer *buffer,
863 struct ring_buffer_event *rbe,
864 void *event)
865{
866 struct hist_trigger_data *hist_data = hist_field->hist_data;
867 struct trace_array *tr = hist_data->event_file->tr;
868
869 u64 ts = ring_buffer_event_time_stamp(buffer, event: rbe);
870
871 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
872 ts = ns2usecs(nsec: ts);
873
874 return ts;
875}
876
877static u64 hist_field_cpu(struct hist_field *hist_field,
878 struct tracing_map_elt *elt,
879 struct trace_buffer *buffer,
880 struct ring_buffer_event *rbe,
881 void *event)
882{
883 int cpu = smp_processor_id();
884
885 return cpu;
886}
887
888/**
889 * check_field_for_var_ref - Check if a VAR_REF field references a variable
890 * @hist_field: The VAR_REF field to check
891 * @var_data: The hist trigger that owns the variable
892 * @var_idx: The trigger variable identifier
893 *
894 * Check the given VAR_REF field to see whether or not it references
895 * the given variable associated with the given trigger.
896 *
897 * Return: The VAR_REF field if it does reference the variable, NULL if not
898 */
899static struct hist_field *
900check_field_for_var_ref(struct hist_field *hist_field,
901 struct hist_trigger_data *var_data,
902 unsigned int var_idx)
903{
904 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
905
906 if (hist_field && hist_field->var.idx == var_idx &&
907 hist_field->var.hist_data == var_data)
908 return hist_field;
909
910 return NULL;
911}
912
913/**
914 * find_var_ref - Check if a trigger has a reference to a trigger variable
915 * @hist_data: The hist trigger that might have a reference to the variable
916 * @var_data: The hist trigger that owns the variable
917 * @var_idx: The trigger variable identifier
918 *
919 * Check the list of var_refs[] on the first hist trigger to see
920 * whether any of them are references to the variable on the second
921 * trigger.
922 *
923 * Return: The VAR_REF field referencing the variable if so, NULL if not
924 */
925static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
926 struct hist_trigger_data *var_data,
927 unsigned int var_idx)
928{
929 struct hist_field *hist_field;
930 unsigned int i;
931
932 for (i = 0; i < hist_data->n_var_refs; i++) {
933 hist_field = hist_data->var_refs[i];
934 if (check_field_for_var_ref(hist_field, var_data, var_idx))
935 return hist_field;
936 }
937
938 return NULL;
939}
940
941/**
942 * find_any_var_ref - Check if there is a reference to a given trigger variable
943 * @hist_data: The hist trigger
944 * @var_idx: The trigger variable identifier
945 *
946 * Check to see whether the given variable is currently referenced by
947 * any other trigger.
948 *
949 * The trigger the variable is defined on is explicitly excluded - the
950 * assumption being that a self-reference doesn't prevent a trigger
951 * from being removed.
952 *
953 * Return: The VAR_REF field referencing the variable if so, NULL if not
954 */
955static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
956 unsigned int var_idx)
957{
958 struct trace_array *tr = hist_data->event_file->tr;
959 struct hist_field *found = NULL;
960 struct hist_var_data *var_data;
961
962 list_for_each_entry(var_data, &tr->hist_vars, list) {
963 if (var_data->hist_data == hist_data)
964 continue;
965 found = find_var_ref(hist_data: var_data->hist_data, var_data: hist_data, var_idx);
966 if (found)
967 break;
968 }
969
970 return found;
971}
972
973/**
974 * check_var_refs - Check if there is a reference to any of trigger's variables
975 * @hist_data: The hist trigger
976 *
977 * A trigger can define one or more variables. If any one of them is
978 * currently referenced by any other trigger, this function will
979 * determine that.
980 *
981 * Typically used to determine whether or not a trigger can be removed
982 * - if there are any references to a trigger's variables, it cannot.
983 *
984 * Return: True if there is a reference to any of trigger's variables
985 */
986static bool check_var_refs(struct hist_trigger_data *hist_data)
987{
988 struct hist_field *field;
989 bool found = false;
990 int i;
991
992 for_each_hist_field(i, hist_data) {
993 field = hist_data->fields[i];
994 if (field && field->flags & HIST_FIELD_FL_VAR) {
995 if (find_any_var_ref(hist_data, var_idx: field->var.idx)) {
996 found = true;
997 break;
998 }
999 }
1000 }
1001
1002 return found;
1003}
1004
1005static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
1006{
1007 struct trace_array *tr = hist_data->event_file->tr;
1008 struct hist_var_data *var_data, *found = NULL;
1009
1010 list_for_each_entry(var_data, &tr->hist_vars, list) {
1011 if (var_data->hist_data == hist_data) {
1012 found = var_data;
1013 break;
1014 }
1015 }
1016
1017 return found;
1018}
1019
1020static bool field_has_hist_vars(struct hist_field *hist_field,
1021 unsigned int level)
1022{
1023 int i;
1024
1025 if (level > 3)
1026 return false;
1027
1028 if (!hist_field)
1029 return false;
1030
1031 if (hist_field->flags & HIST_FIELD_FL_VAR ||
1032 hist_field->flags & HIST_FIELD_FL_VAR_REF)
1033 return true;
1034
1035 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1036 struct hist_field *operand;
1037
1038 operand = hist_field->operands[i];
1039 if (field_has_hist_vars(hist_field: operand, level: level + 1))
1040 return true;
1041 }
1042
1043 return false;
1044}
1045
1046static bool has_hist_vars(struct hist_trigger_data *hist_data)
1047{
1048 struct hist_field *hist_field;
1049 int i;
1050
1051 for_each_hist_field(i, hist_data) {
1052 hist_field = hist_data->fields[i];
1053 if (field_has_hist_vars(hist_field, level: 0))
1054 return true;
1055 }
1056
1057 return false;
1058}
1059
1060static int save_hist_vars(struct hist_trigger_data *hist_data)
1061{
1062 struct trace_array *tr = hist_data->event_file->tr;
1063 struct hist_var_data *var_data;
1064
1065 var_data = find_hist_vars(hist_data);
1066 if (var_data)
1067 return 0;
1068
1069 if (tracing_check_open_get_tr(tr))
1070 return -ENODEV;
1071
1072 var_data = kzalloc(size: sizeof(*var_data), GFP_KERNEL);
1073 if (!var_data) {
1074 trace_array_put(tr);
1075 return -ENOMEM;
1076 }
1077
1078 var_data->hist_data = hist_data;
1079 list_add(new: &var_data->list, head: &tr->hist_vars);
1080
1081 return 0;
1082}
1083
1084static void remove_hist_vars(struct hist_trigger_data *hist_data)
1085{
1086 struct trace_array *tr = hist_data->event_file->tr;
1087 struct hist_var_data *var_data;
1088
1089 var_data = find_hist_vars(hist_data);
1090 if (!var_data)
1091 return;
1092
1093 if (WARN_ON(check_var_refs(hist_data)))
1094 return;
1095
1096 list_del(entry: &var_data->list);
1097
1098 kfree(objp: var_data);
1099
1100 trace_array_put(tr);
1101}
1102
1103static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
1104 const char *var_name)
1105{
1106 struct hist_field *hist_field, *found = NULL;
1107 int i;
1108
1109 for_each_hist_field(i, hist_data) {
1110 hist_field = hist_data->fields[i];
1111 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
1112 strcmp(hist_field->var.name, var_name) == 0) {
1113 found = hist_field;
1114 break;
1115 }
1116 }
1117
1118 return found;
1119}
1120
1121static struct hist_field *find_var(struct hist_trigger_data *hist_data,
1122 struct trace_event_file *file,
1123 const char *var_name)
1124{
1125 struct hist_trigger_data *test_data;
1126 struct event_trigger_data *test;
1127 struct hist_field *hist_field;
1128
1129 lockdep_assert_held(&event_mutex);
1130
1131 hist_field = find_var_field(hist_data, var_name);
1132 if (hist_field)
1133 return hist_field;
1134
1135 list_for_each_entry(test, &file->triggers, list) {
1136 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1137 test_data = test->private_data;
1138 hist_field = find_var_field(hist_data: test_data, var_name);
1139 if (hist_field)
1140 return hist_field;
1141 }
1142 }
1143
1144 return NULL;
1145}
1146
1147static struct trace_event_file *find_var_file(struct trace_array *tr,
1148 char *system,
1149 char *event_name,
1150 char *var_name)
1151{
1152 struct hist_trigger_data *var_hist_data;
1153 struct hist_var_data *var_data;
1154 struct trace_event_file *file, *found = NULL;
1155
1156 if (system)
1157 return find_event_file(tr, system, event: event_name);
1158
1159 list_for_each_entry(var_data, &tr->hist_vars, list) {
1160 var_hist_data = var_data->hist_data;
1161 file = var_hist_data->event_file;
1162 if (file == found)
1163 continue;
1164
1165 if (find_var_field(hist_data: var_hist_data, var_name)) {
1166 if (found) {
1167 hist_err(tr, err_type: HIST_ERR_VAR_NOT_UNIQUE, err_pos: errpos(str: var_name));
1168 return NULL;
1169 }
1170
1171 found = file;
1172 }
1173 }
1174
1175 return found;
1176}
1177
1178static struct hist_field *find_file_var(struct trace_event_file *file,
1179 const char *var_name)
1180{
1181 struct hist_trigger_data *test_data;
1182 struct event_trigger_data *test;
1183 struct hist_field *hist_field;
1184
1185 lockdep_assert_held(&event_mutex);
1186
1187 list_for_each_entry(test, &file->triggers, list) {
1188 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1189 test_data = test->private_data;
1190 hist_field = find_var_field(hist_data: test_data, var_name);
1191 if (hist_field)
1192 return hist_field;
1193 }
1194 }
1195
1196 return NULL;
1197}
1198
1199static struct hist_field *
1200find_match_var(struct hist_trigger_data *hist_data, char *var_name)
1201{
1202 struct trace_array *tr = hist_data->event_file->tr;
1203 struct hist_field *hist_field, *found = NULL;
1204 struct trace_event_file *file;
1205 unsigned int i;
1206
1207 for (i = 0; i < hist_data->n_actions; i++) {
1208 struct action_data *data = hist_data->actions[i];
1209
1210 if (data->handler == HANDLER_ONMATCH) {
1211 char *system = data->match_data.event_system;
1212 char *event_name = data->match_data.event;
1213
1214 file = find_var_file(tr, system, event_name, var_name);
1215 if (!file)
1216 continue;
1217 hist_field = find_file_var(file, var_name);
1218 if (hist_field) {
1219 if (found) {
1220 hist_err(tr, err_type: HIST_ERR_VAR_NOT_UNIQUE,
1221 err_pos: errpos(str: var_name));
1222 return ERR_PTR(error: -EINVAL);
1223 }
1224
1225 found = hist_field;
1226 }
1227 }
1228 }
1229 return found;
1230}
1231
1232static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
1233 char *system,
1234 char *event_name,
1235 char *var_name)
1236{
1237 struct trace_array *tr = hist_data->event_file->tr;
1238 struct hist_field *hist_field = NULL;
1239 struct trace_event_file *file;
1240
1241 if (!system || !event_name) {
1242 hist_field = find_match_var(hist_data, var_name);
1243 if (IS_ERR(ptr: hist_field))
1244 return NULL;
1245 if (hist_field)
1246 return hist_field;
1247 }
1248
1249 file = find_var_file(tr, system, event_name, var_name);
1250 if (!file)
1251 return NULL;
1252
1253 hist_field = find_file_var(file, var_name);
1254
1255 return hist_field;
1256}
1257
1258static u64 hist_field_var_ref(struct hist_field *hist_field,
1259 struct tracing_map_elt *elt,
1260 struct trace_buffer *buffer,
1261 struct ring_buffer_event *rbe,
1262 void *event)
1263{
1264 struct hist_elt_data *elt_data;
1265 u64 var_val = 0;
1266
1267 if (WARN_ON_ONCE(!elt))
1268 return var_val;
1269
1270 elt_data = elt->private_data;
1271 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1272
1273 return var_val;
1274}
1275
1276static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1277 u64 *var_ref_vals, bool self)
1278{
1279 struct hist_trigger_data *var_data;
1280 struct tracing_map_elt *var_elt;
1281 struct hist_field *hist_field;
1282 unsigned int i, var_idx;
1283 bool resolved = true;
1284 u64 var_val = 0;
1285
1286 for (i = 0; i < hist_data->n_var_refs; i++) {
1287 hist_field = hist_data->var_refs[i];
1288 var_idx = hist_field->var.idx;
1289 var_data = hist_field->var.hist_data;
1290
1291 if (var_data == NULL) {
1292 resolved = false;
1293 break;
1294 }
1295
1296 if ((self && var_data != hist_data) ||
1297 (!self && var_data == hist_data))
1298 continue;
1299
1300 var_elt = tracing_map_lookup(map: var_data->map, key);
1301 if (!var_elt) {
1302 resolved = false;
1303 break;
1304 }
1305
1306 if (!tracing_map_var_set(elt: var_elt, i: var_idx)) {
1307 resolved = false;
1308 break;
1309 }
1310
1311 if (self || !hist_field->read_once)
1312 var_val = tracing_map_read_var(elt: var_elt, i: var_idx);
1313 else
1314 var_val = tracing_map_read_var_once(elt: var_elt, i: var_idx);
1315
1316 var_ref_vals[i] = var_val;
1317 }
1318
1319 return resolved;
1320}
1321
1322static const char *hist_field_name(struct hist_field *field,
1323 unsigned int level)
1324{
1325 const char *field_name = "";
1326
1327 if (WARN_ON_ONCE(!field))
1328 return field_name;
1329
1330 if (level > 1)
1331 return field_name;
1332
1333 if (field->field)
1334 field_name = field->field->name;
1335 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1336 field->flags & HIST_FIELD_FL_ALIAS ||
1337 field->flags & HIST_FIELD_FL_BUCKET)
1338 field_name = hist_field_name(field: field->operands[0], level: ++level);
1339 else if (field->flags & HIST_FIELD_FL_CPU)
1340 field_name = "common_cpu";
1341 else if (field->flags & HIST_FIELD_FL_EXPR ||
1342 field->flags & HIST_FIELD_FL_VAR_REF) {
1343 if (field->system) {
1344 static char full_name[MAX_FILTER_STR_VAL];
1345
1346 strcat(p: full_name, q: field->system);
1347 strcat(p: full_name, q: ".");
1348 strcat(p: full_name, q: field->event_name);
1349 strcat(p: full_name, q: ".");
1350 strcat(p: full_name, q: field->name);
1351 field_name = full_name;
1352 } else
1353 field_name = field->name;
1354 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1355 field_name = "common_timestamp";
1356 else if (field->flags & HIST_FIELD_FL_STACKTRACE) {
1357 if (field->field)
1358 field_name = field->field->name;
1359 else
1360 field_name = "common_stacktrace";
1361 } else if (field->flags & HIST_FIELD_FL_HITCOUNT)
1362 field_name = "hitcount";
1363
1364 if (field_name == NULL)
1365 field_name = "";
1366
1367 return field_name;
1368}
1369
1370static enum hist_field_fn select_value_fn(int field_size, int field_is_signed)
1371{
1372 switch (field_size) {
1373 case 8:
1374 if (field_is_signed)
1375 return HIST_FIELD_FN_S64;
1376 else
1377 return HIST_FIELD_FN_U64;
1378 case 4:
1379 if (field_is_signed)
1380 return HIST_FIELD_FN_S32;
1381 else
1382 return HIST_FIELD_FN_U32;
1383 case 2:
1384 if (field_is_signed)
1385 return HIST_FIELD_FN_S16;
1386 else
1387 return HIST_FIELD_FN_U16;
1388 case 1:
1389 if (field_is_signed)
1390 return HIST_FIELD_FN_S8;
1391 else
1392 return HIST_FIELD_FN_U8;
1393 }
1394
1395 return HIST_FIELD_FN_NOP;
1396}
1397
1398static int parse_map_size(char *str)
1399{
1400 unsigned long size, map_bits;
1401 int ret;
1402
1403 ret = kstrtoul(s: str, base: 0, res: &size);
1404 if (ret)
1405 goto out;
1406
1407 map_bits = ilog2(roundup_pow_of_two(size));
1408 if (map_bits < TRACING_MAP_BITS_MIN ||
1409 map_bits > TRACING_MAP_BITS_MAX)
1410 ret = -EINVAL;
1411 else
1412 ret = map_bits;
1413 out:
1414 return ret;
1415}
1416
1417static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1418{
1419 unsigned int i;
1420
1421 if (!attrs)
1422 return;
1423
1424 for (i = 0; i < attrs->n_assignments; i++)
1425 kfree(objp: attrs->assignment_str[i]);
1426
1427 for (i = 0; i < attrs->n_actions; i++)
1428 kfree(objp: attrs->action_str[i]);
1429
1430 kfree(objp: attrs->name);
1431 kfree(objp: attrs->sort_key_str);
1432 kfree(objp: attrs->keys_str);
1433 kfree(objp: attrs->vals_str);
1434 kfree(objp: attrs->clock);
1435 kfree(objp: attrs);
1436}
1437
1438static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1439{
1440 int ret = -EINVAL;
1441
1442 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1443 return ret;
1444
1445 if ((str_has_prefix(str, prefix: "onmatch(")) ||
1446 (str_has_prefix(str, prefix: "onmax(")) ||
1447 (str_has_prefix(str, prefix: "onchange("))) {
1448 attrs->action_str[attrs->n_actions] = kstrdup(s: str, GFP_KERNEL);
1449 if (!attrs->action_str[attrs->n_actions]) {
1450 ret = -ENOMEM;
1451 return ret;
1452 }
1453 attrs->n_actions++;
1454 ret = 0;
1455 }
1456 return ret;
1457}
1458
1459static int parse_assignment(struct trace_array *tr,
1460 char *str, struct hist_trigger_attrs *attrs)
1461{
1462 int len, ret = 0;
1463
1464 if ((len = str_has_prefix(str, prefix: "key=")) ||
1465 (len = str_has_prefix(str, prefix: "keys="))) {
1466 attrs->keys_str = kstrdup(s: str + len, GFP_KERNEL);
1467 if (!attrs->keys_str) {
1468 ret = -ENOMEM;
1469 goto out;
1470 }
1471 } else if ((len = str_has_prefix(str, prefix: "val=")) ||
1472 (len = str_has_prefix(str, prefix: "vals=")) ||
1473 (len = str_has_prefix(str, prefix: "values="))) {
1474 attrs->vals_str = kstrdup(s: str + len, GFP_KERNEL);
1475 if (!attrs->vals_str) {
1476 ret = -ENOMEM;
1477 goto out;
1478 }
1479 } else if ((len = str_has_prefix(str, prefix: "sort="))) {
1480 attrs->sort_key_str = kstrdup(s: str + len, GFP_KERNEL);
1481 if (!attrs->sort_key_str) {
1482 ret = -ENOMEM;
1483 goto out;
1484 }
1485 } else if (str_has_prefix(str, prefix: "name=")) {
1486 attrs->name = kstrdup(s: str, GFP_KERNEL);
1487 if (!attrs->name) {
1488 ret = -ENOMEM;
1489 goto out;
1490 }
1491 } else if ((len = str_has_prefix(str, prefix: "clock="))) {
1492 str += len;
1493
1494 str = strstrip(str);
1495 attrs->clock = kstrdup(s: str, GFP_KERNEL);
1496 if (!attrs->clock) {
1497 ret = -ENOMEM;
1498 goto out;
1499 }
1500 } else if ((len = str_has_prefix(str, prefix: "size="))) {
1501 int map_bits = parse_map_size(str: str + len);
1502
1503 if (map_bits < 0) {
1504 ret = map_bits;
1505 goto out;
1506 }
1507 attrs->map_bits = map_bits;
1508 } else {
1509 char *assignment;
1510
1511 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1512 hist_err(tr, err_type: HIST_ERR_TOO_MANY_VARS, err_pos: errpos(str));
1513 ret = -EINVAL;
1514 goto out;
1515 }
1516
1517 assignment = kstrdup(s: str, GFP_KERNEL);
1518 if (!assignment) {
1519 ret = -ENOMEM;
1520 goto out;
1521 }
1522
1523 attrs->assignment_str[attrs->n_assignments++] = assignment;
1524 }
1525 out:
1526 return ret;
1527}
1528
1529static struct hist_trigger_attrs *
1530parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
1531{
1532 struct hist_trigger_attrs *attrs;
1533 int ret = 0;
1534
1535 attrs = kzalloc(size: sizeof(*attrs), GFP_KERNEL);
1536 if (!attrs)
1537 return ERR_PTR(error: -ENOMEM);
1538
1539 while (trigger_str) {
1540 char *str = strsep(&trigger_str, ":");
1541 char *rhs;
1542
1543 rhs = strchr(str, '=');
1544 if (rhs) {
1545 if (!strlen(++rhs)) {
1546 ret = -EINVAL;
1547 hist_err(tr, err_type: HIST_ERR_EMPTY_ASSIGNMENT, err_pos: errpos(str));
1548 goto free;
1549 }
1550 ret = parse_assignment(tr, str, attrs);
1551 if (ret)
1552 goto free;
1553 } else if (strcmp(str, "nohitcount") == 0 ||
1554 strcmp(str, "NOHC") == 0)
1555 attrs->no_hitcount = true;
1556 else if (strcmp(str, "pause") == 0)
1557 attrs->pause = true;
1558 else if ((strcmp(str, "cont") == 0) ||
1559 (strcmp(str, "continue") == 0))
1560 attrs->cont = true;
1561 else if (strcmp(str, "clear") == 0)
1562 attrs->clear = true;
1563 else {
1564 ret = parse_action(str, attrs);
1565 if (ret)
1566 goto free;
1567 }
1568 }
1569
1570 if (!attrs->keys_str) {
1571 ret = -EINVAL;
1572 goto free;
1573 }
1574
1575 if (!attrs->clock) {
1576 attrs->clock = kstrdup(s: "global", GFP_KERNEL);
1577 if (!attrs->clock) {
1578 ret = -ENOMEM;
1579 goto free;
1580 }
1581 }
1582
1583 return attrs;
1584 free:
1585 destroy_hist_trigger_attrs(attrs);
1586
1587 return ERR_PTR(error: ret);
1588}
1589
1590static inline void save_comm(char *comm, struct task_struct *task)
1591{
1592 if (!task->pid) {
1593 strcpy(p: comm, q: "<idle>");
1594 return;
1595 }
1596
1597 if (WARN_ON_ONCE(task->pid < 0)) {
1598 strcpy(p: comm, q: "<XXX>");
1599 return;
1600 }
1601
1602 strncpy(p: comm, q: task->comm, size: TASK_COMM_LEN);
1603}
1604
1605static void hist_elt_data_free(struct hist_elt_data *elt_data)
1606{
1607 unsigned int i;
1608
1609 for (i = 0; i < elt_data->n_field_var_str; i++)
1610 kfree(objp: elt_data->field_var_str[i]);
1611
1612 kfree(objp: elt_data->field_var_str);
1613
1614 kfree(objp: elt_data->comm);
1615 kfree(objp: elt_data);
1616}
1617
1618static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1619{
1620 struct hist_elt_data *elt_data = elt->private_data;
1621
1622 hist_elt_data_free(elt_data);
1623}
1624
1625static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1626{
1627 struct hist_trigger_data *hist_data = elt->map->private_data;
1628 unsigned int size = TASK_COMM_LEN;
1629 struct hist_elt_data *elt_data;
1630 struct hist_field *hist_field;
1631 unsigned int i, n_str;
1632
1633 elt_data = kzalloc(size: sizeof(*elt_data), GFP_KERNEL);
1634 if (!elt_data)
1635 return -ENOMEM;
1636
1637 for_each_hist_field(i, hist_data) {
1638 hist_field = hist_data->fields[i];
1639
1640 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) {
1641 elt_data->comm = kzalloc(size, GFP_KERNEL);
1642 if (!elt_data->comm) {
1643 kfree(objp: elt_data);
1644 return -ENOMEM;
1645 }
1646 break;
1647 }
1648 }
1649
1650 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str +
1651 hist_data->n_var_str;
1652 if (n_str > SYNTH_FIELDS_MAX) {
1653 hist_elt_data_free(elt_data);
1654 return -EINVAL;
1655 }
1656
1657 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1));
1658
1659 size = STR_VAR_LEN_MAX;
1660
1661 elt_data->field_var_str = kcalloc(n: n_str, size: sizeof(char *), GFP_KERNEL);
1662 if (!elt_data->field_var_str) {
1663 hist_elt_data_free(elt_data);
1664 return -EINVAL;
1665 }
1666 elt_data->n_field_var_str = n_str;
1667
1668 for (i = 0; i < n_str; i++) {
1669 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
1670 if (!elt_data->field_var_str[i]) {
1671 hist_elt_data_free(elt_data);
1672 return -ENOMEM;
1673 }
1674 }
1675
1676 elt->private_data = elt_data;
1677
1678 return 0;
1679}
1680
1681static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
1682{
1683 struct hist_elt_data *elt_data = elt->private_data;
1684
1685 if (elt_data->comm)
1686 save_comm(comm: elt_data->comm, current);
1687}
1688
1689static const struct tracing_map_ops hist_trigger_elt_data_ops = {
1690 .elt_alloc = hist_trigger_elt_data_alloc,
1691 .elt_free = hist_trigger_elt_data_free,
1692 .elt_init = hist_trigger_elt_data_init,
1693};
1694
1695static const char *get_hist_field_flags(struct hist_field *hist_field)
1696{
1697 const char *flags_str = NULL;
1698
1699 if (hist_field->flags & HIST_FIELD_FL_HEX)
1700 flags_str = "hex";
1701 else if (hist_field->flags & HIST_FIELD_FL_SYM)
1702 flags_str = "sym";
1703 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
1704 flags_str = "sym-offset";
1705 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
1706 flags_str = "execname";
1707 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
1708 flags_str = "syscall";
1709 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
1710 flags_str = "log2";
1711 else if (hist_field->flags & HIST_FIELD_FL_BUCKET)
1712 flags_str = "buckets";
1713 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1714 flags_str = "usecs";
1715 else if (hist_field->flags & HIST_FIELD_FL_PERCENT)
1716 flags_str = "percent";
1717 else if (hist_field->flags & HIST_FIELD_FL_GRAPH)
1718 flags_str = "graph";
1719 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
1720 flags_str = "stacktrace";
1721
1722 return flags_str;
1723}
1724
1725static void expr_field_str(struct hist_field *field, char *expr)
1726{
1727 if (field->flags & HIST_FIELD_FL_VAR_REF)
1728 strcat(p: expr, q: "$");
1729 else if (field->flags & HIST_FIELD_FL_CONST) {
1730 char str[HIST_CONST_DIGITS_MAX];
1731
1732 snprintf(buf: str, HIST_CONST_DIGITS_MAX, fmt: "%llu", field->constant);
1733 strcat(p: expr, q: str);
1734 }
1735
1736 strcat(p: expr, q: hist_field_name(field, level: 0));
1737
1738 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
1739 const char *flags_str = get_hist_field_flags(hist_field: field);
1740
1741 if (flags_str) {
1742 strcat(p: expr, q: ".");
1743 strcat(p: expr, q: flags_str);
1744 }
1745 }
1746}
1747
1748static char *expr_str(struct hist_field *field, unsigned int level)
1749{
1750 char *expr;
1751
1752 if (level > 1)
1753 return NULL;
1754
1755 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
1756 if (!expr)
1757 return NULL;
1758
1759 if (!field->operands[0]) {
1760 expr_field_str(field, expr);
1761 return expr;
1762 }
1763
1764 if (field->operator == FIELD_OP_UNARY_MINUS) {
1765 char *subexpr;
1766
1767 strcat(p: expr, q: "-(");
1768 subexpr = expr_str(field: field->operands[0], level: ++level);
1769 if (!subexpr) {
1770 kfree(objp: expr);
1771 return NULL;
1772 }
1773 strcat(p: expr, q: subexpr);
1774 strcat(p: expr, q: ")");
1775
1776 kfree(objp: subexpr);
1777
1778 return expr;
1779 }
1780
1781 expr_field_str(field: field->operands[0], expr);
1782
1783 switch (field->operator) {
1784 case FIELD_OP_MINUS:
1785 strcat(p: expr, q: "-");
1786 break;
1787 case FIELD_OP_PLUS:
1788 strcat(p: expr, q: "+");
1789 break;
1790 case FIELD_OP_DIV:
1791 strcat(p: expr, q: "/");
1792 break;
1793 case FIELD_OP_MULT:
1794 strcat(p: expr, q: "*");
1795 break;
1796 default:
1797 kfree(objp: expr);
1798 return NULL;
1799 }
1800
1801 expr_field_str(field: field->operands[1], expr);
1802
1803 return expr;
1804}
1805
1806/*
1807 * If field_op != FIELD_OP_NONE, *sep points to the root operator
1808 * of the expression tree to be evaluated.
1809 */
1810static int contains_operator(char *str, char **sep)
1811{
1812 enum field_op_id field_op = FIELD_OP_NONE;
1813 char *minus_op, *plus_op, *div_op, *mult_op;
1814
1815
1816 /*
1817 * Report the last occurrence of the operators first, so that the
1818 * expression is evaluated left to right. This is important since
1819 * subtraction and division are not associative.
1820 *
1821 * e.g
1822 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2
1823 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2
1824 */
1825
1826 /*
1827 * First, find lower precedence addition and subtraction
1828 * since the expression will be evaluated recursively.
1829 */
1830 minus_op = strrchr(str, '-');
1831 if (minus_op) {
1832 /*
1833 * Unary minus is not supported in sub-expressions. If
1834 * present, it is always the next root operator.
1835 */
1836 if (minus_op == str) {
1837 field_op = FIELD_OP_UNARY_MINUS;
1838 goto out;
1839 }
1840
1841 field_op = FIELD_OP_MINUS;
1842 }
1843
1844 plus_op = strrchr(str, '+');
1845 if (plus_op || minus_op) {
1846 /*
1847 * For operators of the same precedence use to rightmost as the
1848 * root, so that the expression is evaluated left to right.
1849 */
1850 if (plus_op > minus_op)
1851 field_op = FIELD_OP_PLUS;
1852 goto out;
1853 }
1854
1855 /*
1856 * Multiplication and division have higher precedence than addition and
1857 * subtraction.
1858 */
1859 div_op = strrchr(str, '/');
1860 if (div_op)
1861 field_op = FIELD_OP_DIV;
1862
1863 mult_op = strrchr(str, '*');
1864 /*
1865 * For operators of the same precedence use to rightmost as the
1866 * root, so that the expression is evaluated left to right.
1867 */
1868 if (mult_op > div_op)
1869 field_op = FIELD_OP_MULT;
1870
1871out:
1872 if (sep) {
1873 switch (field_op) {
1874 case FIELD_OP_UNARY_MINUS:
1875 case FIELD_OP_MINUS:
1876 *sep = minus_op;
1877 break;
1878 case FIELD_OP_PLUS:
1879 *sep = plus_op;
1880 break;
1881 case FIELD_OP_DIV:
1882 *sep = div_op;
1883 break;
1884 case FIELD_OP_MULT:
1885 *sep = mult_op;
1886 break;
1887 case FIELD_OP_NONE:
1888 default:
1889 *sep = NULL;
1890 break;
1891 }
1892 }
1893
1894 return field_op;
1895}
1896
1897static void get_hist_field(struct hist_field *hist_field)
1898{
1899 hist_field->ref++;
1900}
1901
1902static void __destroy_hist_field(struct hist_field *hist_field)
1903{
1904 if (--hist_field->ref > 1)
1905 return;
1906
1907 kfree(objp: hist_field->var.name);
1908 kfree(objp: hist_field->name);
1909
1910 /* Can likely be a const */
1911 kfree_const(x: hist_field->type);
1912
1913 kfree(objp: hist_field->system);
1914 kfree(objp: hist_field->event_name);
1915
1916 kfree(objp: hist_field);
1917}
1918
1919static void destroy_hist_field(struct hist_field *hist_field,
1920 unsigned int level)
1921{
1922 unsigned int i;
1923
1924 if (level > 3)
1925 return;
1926
1927 if (!hist_field)
1928 return;
1929
1930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
1931 return; /* var refs will be destroyed separately */
1932
1933 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
1934 destroy_hist_field(hist_field: hist_field->operands[i], level: level + 1);
1935
1936 __destroy_hist_field(hist_field);
1937}
1938
1939static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
1940 struct ftrace_event_field *field,
1941 unsigned long flags,
1942 char *var_name)
1943{
1944 struct hist_field *hist_field;
1945
1946 if (field && is_function_field(field))
1947 return NULL;
1948
1949 hist_field = kzalloc(size: sizeof(struct hist_field), GFP_KERNEL);
1950 if (!hist_field)
1951 return NULL;
1952
1953 hist_field->ref = 1;
1954
1955 hist_field->hist_data = hist_data;
1956
1957 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
1958 goto out; /* caller will populate */
1959
1960 if (flags & HIST_FIELD_FL_VAR_REF) {
1961 hist_field->fn_num = HIST_FIELD_FN_VAR_REF;
1962 goto out;
1963 }
1964
1965 if (flags & HIST_FIELD_FL_HITCOUNT) {
1966 hist_field->fn_num = HIST_FIELD_FN_COUNTER;
1967 hist_field->size = sizeof(u64);
1968 hist_field->type = "u64";
1969 goto out;
1970 }
1971
1972 if (flags & HIST_FIELD_FL_CONST) {
1973 hist_field->fn_num = HIST_FIELD_FN_CONST;
1974 hist_field->size = sizeof(u64);
1975 hist_field->type = kstrdup(s: "u64", GFP_KERNEL);
1976 if (!hist_field->type)
1977 goto free;
1978 goto out;
1979 }
1980
1981 if (flags & HIST_FIELD_FL_STACKTRACE) {
1982 if (field)
1983 hist_field->fn_num = HIST_FIELD_FN_STACK;
1984 else
1985 hist_field->fn_num = HIST_FIELD_FN_NOP;
1986 hist_field->size = HIST_STACKTRACE_SIZE;
1987 hist_field->type = kstrdup_const(s: "unsigned long[]", GFP_KERNEL);
1988 if (!hist_field->type)
1989 goto free;
1990 goto out;
1991 }
1992
1993 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) {
1994 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET);
1995 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 :
1996 HIST_FIELD_FN_BUCKET;
1997 hist_field->operands[0] = create_hist_field(hist_data, field, flags: fl, NULL);
1998 if (!hist_field->operands[0])
1999 goto free;
2000 hist_field->size = hist_field->operands[0]->size;
2001 hist_field->type = kstrdup_const(s: hist_field->operands[0]->type, GFP_KERNEL);
2002 if (!hist_field->type)
2003 goto free;
2004 goto out;
2005 }
2006
2007 if (flags & HIST_FIELD_FL_TIMESTAMP) {
2008 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP;
2009 hist_field->size = sizeof(u64);
2010 hist_field->type = "u64";
2011 goto out;
2012 }
2013
2014 if (flags & HIST_FIELD_FL_CPU) {
2015 hist_field->fn_num = HIST_FIELD_FN_CPU;
2016 hist_field->size = sizeof(int);
2017 hist_field->type = "unsigned int";
2018 goto out;
2019 }
2020
2021 if (WARN_ON_ONCE(!field))
2022 goto out;
2023
2024 /* Pointers to strings are just pointers and dangerous to dereference */
2025 if (is_string_field(field) &&
2026 (field->filter_type != FILTER_PTR_STRING)) {
2027 flags |= HIST_FIELD_FL_STRING;
2028
2029 hist_field->size = MAX_FILTER_STR_VAL;
2030 hist_field->type = kstrdup_const(s: field->type, GFP_KERNEL);
2031 if (!hist_field->type)
2032 goto free;
2033
2034 if (field->filter_type == FILTER_STATIC_STRING) {
2035 hist_field->fn_num = HIST_FIELD_FN_STRING;
2036 hist_field->size = field->size;
2037 } else if (field->filter_type == FILTER_DYN_STRING) {
2038 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING;
2039 } else if (field->filter_type == FILTER_RDYN_STRING)
2040 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING;
2041 else
2042 hist_field->fn_num = HIST_FIELD_FN_PSTRING;
2043 } else {
2044 hist_field->size = field->size;
2045 hist_field->is_signed = field->is_signed;
2046 hist_field->type = kstrdup_const(s: field->type, GFP_KERNEL);
2047 if (!hist_field->type)
2048 goto free;
2049
2050 hist_field->fn_num = select_value_fn(field_size: field->size,
2051 field_is_signed: field->is_signed);
2052 if (hist_field->fn_num == HIST_FIELD_FN_NOP) {
2053 destroy_hist_field(hist_field, level: 0);
2054 return NULL;
2055 }
2056 }
2057 out:
2058 hist_field->field = field;
2059 hist_field->flags = flags;
2060
2061 if (var_name) {
2062 hist_field->var.name = kstrdup(s: var_name, GFP_KERNEL);
2063 if (!hist_field->var.name)
2064 goto free;
2065 }
2066
2067 return hist_field;
2068 free:
2069 destroy_hist_field(hist_field, level: 0);
2070 return NULL;
2071}
2072
2073static void destroy_hist_fields(struct hist_trigger_data *hist_data)
2074{
2075 unsigned int i;
2076
2077 for (i = 0; i < HIST_FIELDS_MAX; i++) {
2078 if (hist_data->fields[i]) {
2079 destroy_hist_field(hist_field: hist_data->fields[i], level: 0);
2080 hist_data->fields[i] = NULL;
2081 }
2082 }
2083
2084 for (i = 0; i < hist_data->n_var_refs; i++) {
2085 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF));
2086 __destroy_hist_field(hist_field: hist_data->var_refs[i]);
2087 hist_data->var_refs[i] = NULL;
2088 }
2089}
2090
2091static int init_var_ref(struct hist_field *ref_field,
2092 struct hist_field *var_field,
2093 char *system, char *event_name)
2094{
2095 int err = 0;
2096
2097 ref_field->var.idx = var_field->var.idx;
2098 ref_field->var.hist_data = var_field->hist_data;
2099 ref_field->size = var_field->size;
2100 ref_field->is_signed = var_field->is_signed;
2101 ref_field->flags |= var_field->flags &
2102 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2103
2104 if (system) {
2105 ref_field->system = kstrdup(s: system, GFP_KERNEL);
2106 if (!ref_field->system)
2107 return -ENOMEM;
2108 }
2109
2110 if (event_name) {
2111 ref_field->event_name = kstrdup(s: event_name, GFP_KERNEL);
2112 if (!ref_field->event_name) {
2113 err = -ENOMEM;
2114 goto free;
2115 }
2116 }
2117
2118 if (var_field->var.name) {
2119 ref_field->name = kstrdup(s: var_field->var.name, GFP_KERNEL);
2120 if (!ref_field->name) {
2121 err = -ENOMEM;
2122 goto free;
2123 }
2124 } else if (var_field->name) {
2125 ref_field->name = kstrdup(s: var_field->name, GFP_KERNEL);
2126 if (!ref_field->name) {
2127 err = -ENOMEM;
2128 goto free;
2129 }
2130 }
2131
2132 ref_field->type = kstrdup_const(s: var_field->type, GFP_KERNEL);
2133 if (!ref_field->type) {
2134 err = -ENOMEM;
2135 goto free;
2136 }
2137 out:
2138 return err;
2139 free:
2140 kfree(objp: ref_field->system);
2141 ref_field->system = NULL;
2142 kfree(objp: ref_field->event_name);
2143 ref_field->event_name = NULL;
2144 kfree(objp: ref_field->name);
2145 ref_field->name = NULL;
2146
2147 goto out;
2148}
2149
2150static int find_var_ref_idx(struct hist_trigger_data *hist_data,
2151 struct hist_field *var_field)
2152{
2153 struct hist_field *ref_field;
2154 int i;
2155
2156 for (i = 0; i < hist_data->n_var_refs; i++) {
2157 ref_field = hist_data->var_refs[i];
2158 if (ref_field->var.idx == var_field->var.idx &&
2159 ref_field->var.hist_data == var_field->hist_data)
2160 return i;
2161 }
2162
2163 return -ENOENT;
2164}
2165
2166/**
2167 * create_var_ref - Create a variable reference and attach it to trigger
2168 * @hist_data: The trigger that will be referencing the variable
2169 * @var_field: The VAR field to create a reference to
2170 * @system: The optional system string
2171 * @event_name: The optional event_name string
2172 *
2173 * Given a variable hist_field, create a VAR_REF hist_field that
2174 * represents a reference to it.
2175 *
2176 * This function also adds the reference to the trigger that
2177 * now references the variable.
2178 *
2179 * Return: The VAR_REF field if successful, NULL if not
2180 */
2181static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
2182 struct hist_field *var_field,
2183 char *system, char *event_name)
2184{
2185 unsigned long flags = HIST_FIELD_FL_VAR_REF;
2186 struct hist_field *ref_field;
2187 int i;
2188
2189 /* Check if the variable already exists */
2190 for (i = 0; i < hist_data->n_var_refs; i++) {
2191 ref_field = hist_data->var_refs[i];
2192 if (ref_field->var.idx == var_field->var.idx &&
2193 ref_field->var.hist_data == var_field->hist_data) {
2194 get_hist_field(hist_field: ref_field);
2195 return ref_field;
2196 }
2197 }
2198 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */
2199 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX)
2200 return NULL;
2201 ref_field = create_hist_field(hist_data: var_field->hist_data, NULL, flags, NULL);
2202 if (ref_field) {
2203 if (init_var_ref(ref_field, var_field, system, event_name)) {
2204 destroy_hist_field(hist_field: ref_field, level: 0);
2205 return NULL;
2206 }
2207
2208 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
2209 ref_field->var_ref_idx = hist_data->n_var_refs++;
2210 }
2211
2212 return ref_field;
2213}
2214
2215static bool is_var_ref(char *var_name)
2216{
2217 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
2218 return false;
2219
2220 return true;
2221}
2222
2223static char *field_name_from_var(struct hist_trigger_data *hist_data,
2224 char *var_name)
2225{
2226 char *name, *field;
2227 unsigned int i;
2228
2229 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
2230 name = hist_data->attrs->var_defs.name[i];
2231
2232 if (strcmp(var_name, name) == 0) {
2233 field = hist_data->attrs->var_defs.expr[i];
2234 if (contains_operator(str: field, NULL) || is_var_ref(var_name: field))
2235 continue;
2236 return field;
2237 }
2238 }
2239
2240 return NULL;
2241}
2242
2243static char *local_field_var_ref(struct hist_trigger_data *hist_data,
2244 char *system, char *event_name,
2245 char *var_name)
2246{
2247 struct trace_event_call *call;
2248
2249 if (system && event_name) {
2250 call = hist_data->event_file->event_call;
2251
2252 if (strcmp(system, call->class->system) != 0)
2253 return NULL;
2254
2255 if (strcmp(event_name, trace_event_name(call)) != 0)
2256 return NULL;
2257 }
2258
2259 if (!!system != !!event_name)
2260 return NULL;
2261
2262 if (!is_var_ref(var_name))
2263 return NULL;
2264
2265 var_name++;
2266
2267 return field_name_from_var(hist_data, var_name);
2268}
2269
2270static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
2271 char *system, char *event_name,
2272 char *var_name)
2273{
2274 struct hist_field *var_field = NULL, *ref_field = NULL;
2275 struct trace_array *tr = hist_data->event_file->tr;
2276
2277 if (!is_var_ref(var_name))
2278 return NULL;
2279
2280 var_name++;
2281
2282 var_field = find_event_var(hist_data, system, event_name, var_name);
2283 if (var_field)
2284 ref_field = create_var_ref(hist_data, var_field,
2285 system, event_name);
2286
2287 if (!ref_field)
2288 hist_err(tr, err_type: HIST_ERR_VAR_NOT_FOUND, err_pos: errpos(str: var_name));
2289
2290 return ref_field;
2291}
2292
2293static struct ftrace_event_field *
2294parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
2295 char *field_str, unsigned long *flags, unsigned long *buckets)
2296{
2297 struct ftrace_event_field *field = NULL;
2298 char *field_name, *modifier, *str;
2299 struct trace_array *tr = file->tr;
2300
2301 modifier = str = kstrdup(s: field_str, GFP_KERNEL);
2302 if (!modifier)
2303 return ERR_PTR(error: -ENOMEM);
2304
2305 field_name = strsep(&modifier, ".");
2306 if (modifier) {
2307 if (strcmp(modifier, "hex") == 0)
2308 *flags |= HIST_FIELD_FL_HEX;
2309 else if (strcmp(modifier, "sym") == 0)
2310 *flags |= HIST_FIELD_FL_SYM;
2311 /*
2312 * 'sym-offset' occurrences in the trigger string are modified
2313 * to 'symXoffset' to simplify arithmetic expression parsing.
2314 */
2315 else if (strcmp(modifier, "symXoffset") == 0)
2316 *flags |= HIST_FIELD_FL_SYM_OFFSET;
2317 else if ((strcmp(modifier, "execname") == 0) &&
2318 (strcmp(field_name, "common_pid") == 0))
2319 *flags |= HIST_FIELD_FL_EXECNAME;
2320 else if (strcmp(modifier, "syscall") == 0)
2321 *flags |= HIST_FIELD_FL_SYSCALL;
2322 else if (strcmp(modifier, "stacktrace") == 0)
2323 *flags |= HIST_FIELD_FL_STACKTRACE;
2324 else if (strcmp(modifier, "log2") == 0)
2325 *flags |= HIST_FIELD_FL_LOG2;
2326 else if (strcmp(modifier, "usecs") == 0)
2327 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
2328 else if (strncmp(modifier, "bucket", 6) == 0) {
2329 int ret;
2330
2331 modifier += 6;
2332
2333 if (*modifier == 's')
2334 modifier++;
2335 if (*modifier != '=')
2336 goto error;
2337 modifier++;
2338 ret = kstrtoul(s: modifier, base: 0, res: buckets);
2339 if (ret || !(*buckets))
2340 goto error;
2341 *flags |= HIST_FIELD_FL_BUCKET;
2342 } else if (strncmp(modifier, "percent", 7) == 0) {
2343 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY))
2344 goto error;
2345 *flags |= HIST_FIELD_FL_PERCENT;
2346 } else if (strncmp(modifier, "graph", 5) == 0) {
2347 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY))
2348 goto error;
2349 *flags |= HIST_FIELD_FL_GRAPH;
2350 } else {
2351 error:
2352 hist_err(tr, err_type: HIST_ERR_BAD_FIELD_MODIFIER, err_pos: errpos(str: modifier));
2353 field = ERR_PTR(error: -EINVAL);
2354 goto out;
2355 }
2356 }
2357
2358 if (strcmp(field_name, "common_timestamp") == 0) {
2359 *flags |= HIST_FIELD_FL_TIMESTAMP;
2360 hist_data->enable_timestamps = true;
2361 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2362 hist_data->attrs->ts_in_usecs = true;
2363 } else if (strcmp(field_name, "common_stacktrace") == 0) {
2364 *flags |= HIST_FIELD_FL_STACKTRACE;
2365 } else if (strcmp(field_name, "common_cpu") == 0)
2366 *flags |= HIST_FIELD_FL_CPU;
2367 else if (strcmp(field_name, "hitcount") == 0)
2368 *flags |= HIST_FIELD_FL_HITCOUNT;
2369 else {
2370 field = trace_find_event_field(call: file->event_call, name: field_name);
2371 if (!field || !field->size) {
2372 /*
2373 * For backward compatibility, if field_name
2374 * was "cpu" or "stacktrace", then we treat this
2375 * the same as common_cpu and common_stacktrace
2376 * respectively. This also works for "CPU", and
2377 * "STACKTRACE".
2378 */
2379 if (field && field->filter_type == FILTER_CPU) {
2380 *flags |= HIST_FIELD_FL_CPU;
2381 } else if (field && field->filter_type == FILTER_STACKTRACE) {
2382 *flags |= HIST_FIELD_FL_STACKTRACE;
2383 } else {
2384 hist_err(tr, err_type: HIST_ERR_FIELD_NOT_FOUND,
2385 err_pos: errpos(str: field_name));
2386 field = ERR_PTR(error: -EINVAL);
2387 goto out;
2388 }
2389 }
2390 }
2391 out:
2392 kfree(objp: str);
2393
2394 return field;
2395}
2396
2397static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2398 struct hist_field *var_ref,
2399 char *var_name)
2400{
2401 struct hist_field *alias = NULL;
2402 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2403
2404 alias = create_hist_field(hist_data, NULL, flags, var_name);
2405 if (!alias)
2406 return NULL;
2407
2408 alias->fn_num = var_ref->fn_num;
2409 alias->operands[0] = var_ref;
2410
2411 if (init_var_ref(ref_field: alias, var_field: var_ref, system: var_ref->system, event_name: var_ref->event_name)) {
2412 destroy_hist_field(hist_field: alias, level: 0);
2413 return NULL;
2414 }
2415
2416 alias->var_ref_idx = var_ref->var_ref_idx;
2417
2418 return alias;
2419}
2420
2421static struct hist_field *parse_const(struct hist_trigger_data *hist_data,
2422 char *str, char *var_name,
2423 unsigned long *flags)
2424{
2425 struct trace_array *tr = hist_data->event_file->tr;
2426 struct hist_field *field = NULL;
2427 u64 constant;
2428
2429 if (kstrtoull(s: str, base: 0, res: &constant)) {
2430 hist_err(tr, err_type: HIST_ERR_EXPECT_NUMBER, err_pos: errpos(str));
2431 return NULL;
2432 }
2433
2434 *flags |= HIST_FIELD_FL_CONST;
2435 field = create_hist_field(hist_data, NULL, flags: *flags, var_name);
2436 if (!field)
2437 return NULL;
2438
2439 field->constant = constant;
2440
2441 return field;
2442}
2443
2444static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2445 struct trace_event_file *file, char *str,
2446 unsigned long *flags, char *var_name)
2447{
2448 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2449 struct ftrace_event_field *field = NULL;
2450 struct hist_field *hist_field = NULL;
2451 unsigned long buckets = 0;
2452 int ret = 0;
2453
2454 if (isdigit(c: str[0])) {
2455 hist_field = parse_const(hist_data, str, var_name, flags);
2456 if (!hist_field) {
2457 ret = -EINVAL;
2458 goto out;
2459 }
2460 return hist_field;
2461 }
2462
2463 s = strchr(str, '.');
2464 if (s) {
2465 s = strchr(++s, '.');
2466 if (s) {
2467 ref_system = strsep(&str, ".");
2468 if (!str) {
2469 ret = -EINVAL;
2470 goto out;
2471 }
2472 ref_event = strsep(&str, ".");
2473 if (!str) {
2474 ret = -EINVAL;
2475 goto out;
2476 }
2477 ref_var = str;
2478 }
2479 }
2480
2481 s = local_field_var_ref(hist_data, system: ref_system, event_name: ref_event, var_name: ref_var);
2482 if (!s) {
2483 hist_field = parse_var_ref(hist_data, system: ref_system,
2484 event_name: ref_event, var_name: ref_var);
2485 if (hist_field) {
2486 if (var_name) {
2487 hist_field = create_alias(hist_data, var_ref: hist_field, var_name);
2488 if (!hist_field) {
2489 ret = -ENOMEM;
2490 goto out;
2491 }
2492 }
2493 return hist_field;
2494 }
2495 } else
2496 str = s;
2497
2498 field = parse_field(hist_data, file, field_str: str, flags, buckets: &buckets);
2499 if (IS_ERR(ptr: field)) {
2500 ret = PTR_ERR(ptr: field);
2501 goto out;
2502 }
2503
2504 hist_field = create_hist_field(hist_data, field, flags: *flags, var_name);
2505 if (!hist_field) {
2506 ret = -ENOMEM;
2507 goto out;
2508 }
2509 hist_field->buckets = buckets;
2510
2511 return hist_field;
2512 out:
2513 return ERR_PTR(error: ret);
2514}
2515
2516static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2517 struct trace_event_file *file,
2518 char *str, unsigned long flags,
2519 char *var_name, unsigned int *n_subexprs);
2520
2521static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2522 struct trace_event_file *file,
2523 char *str, unsigned long flags,
2524 char *var_name, unsigned int *n_subexprs)
2525{
2526 struct hist_field *operand1, *expr = NULL;
2527 unsigned long operand_flags;
2528 int ret = 0;
2529 char *s;
2530
2531 /* Unary minus operator, increment n_subexprs */
2532 ++*n_subexprs;
2533
2534 /* we support only -(xxx) i.e. explicit parens required */
2535
2536 if (*n_subexprs > 3) {
2537 hist_err(tr: file->tr, err_type: HIST_ERR_TOO_MANY_SUBEXPR, err_pos: errpos(str));
2538 ret = -EINVAL;
2539 goto free;
2540 }
2541
2542 str++; /* skip leading '-' */
2543
2544 s = strchr(str, '(');
2545 if (s)
2546 str++;
2547 else {
2548 ret = -EINVAL;
2549 goto free;
2550 }
2551
2552 s = strrchr(str, ')');
2553 if (s) {
2554 /* unary minus not supported in sub-expressions */
2555 if (*(s+1) != '\0') {
2556 hist_err(tr: file->tr, err_type: HIST_ERR_UNARY_MINUS_SUBEXPR,
2557 err_pos: errpos(str));
2558 ret = -EINVAL;
2559 goto free;
2560 }
2561 *s = '\0';
2562 }
2563 else {
2564 ret = -EINVAL; /* no closing ')' */
2565 goto free;
2566 }
2567
2568 flags |= HIST_FIELD_FL_EXPR;
2569 expr = create_hist_field(hist_data, NULL, flags, var_name);
2570 if (!expr) {
2571 ret = -ENOMEM;
2572 goto free;
2573 }
2574
2575 operand_flags = 0;
2576 operand1 = parse_expr(hist_data, file, str, flags: operand_flags, NULL, n_subexprs);
2577 if (IS_ERR(ptr: operand1)) {
2578 ret = PTR_ERR(ptr: operand1);
2579 goto free;
2580 }
2581 if (operand1->flags & HIST_FIELD_FL_STRING) {
2582 /* String type can not be the operand of unary operator. */
2583 hist_err(tr: file->tr, err_type: HIST_ERR_INVALID_STR_OPERAND, err_pos: errpos(str));
2584 destroy_hist_field(hist_field: operand1, level: 0);
2585 ret = -EINVAL;
2586 goto free;
2587 }
2588
2589 expr->flags |= operand1->flags &
2590 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2591 expr->fn_num = HIST_FIELD_FN_UMINUS;
2592 expr->operands[0] = operand1;
2593 expr->size = operand1->size;
2594 expr->is_signed = operand1->is_signed;
2595 expr->operator = FIELD_OP_UNARY_MINUS;
2596 expr->name = expr_str(field: expr, level: 0);
2597 expr->type = kstrdup_const(s: operand1->type, GFP_KERNEL);
2598 if (!expr->type) {
2599 ret = -ENOMEM;
2600 goto free;
2601 }
2602
2603 return expr;
2604 free:
2605 destroy_hist_field(hist_field: expr, level: 0);
2606 return ERR_PTR(error: ret);
2607}
2608
2609/*
2610 * If the operands are var refs, return pointers the
2611 * variable(s) referenced in var1 and var2, else NULL.
2612 */
2613static int check_expr_operands(struct trace_array *tr,
2614 struct hist_field *operand1,
2615 struct hist_field *operand2,
2616 struct hist_field **var1,
2617 struct hist_field **var2)
2618{
2619 unsigned long operand1_flags = operand1->flags;
2620 unsigned long operand2_flags = operand2->flags;
2621
2622 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2623 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2624 struct hist_field *var;
2625
2626 var = find_var_field(hist_data: operand1->var.hist_data, var_name: operand1->name);
2627 if (!var)
2628 return -EINVAL;
2629 operand1_flags = var->flags;
2630 *var1 = var;
2631 }
2632
2633 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2634 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2635 struct hist_field *var;
2636
2637 var = find_var_field(hist_data: operand2->var.hist_data, var_name: operand2->name);
2638 if (!var)
2639 return -EINVAL;
2640 operand2_flags = var->flags;
2641 *var2 = var;
2642 }
2643
2644 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2645 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2646 hist_err(tr, err_type: HIST_ERR_TIMESTAMP_MISMATCH, err_pos: 0);
2647 return -EINVAL;
2648 }
2649
2650 return 0;
2651}
2652
2653static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2654 struct trace_event_file *file,
2655 char *str, unsigned long flags,
2656 char *var_name, unsigned int *n_subexprs)
2657{
2658 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2659 struct hist_field *var1 = NULL, *var2 = NULL;
2660 unsigned long operand_flags, operand2_flags;
2661 int field_op, ret = -EINVAL;
2662 char *sep, *operand1_str;
2663 enum hist_field_fn op_fn;
2664 bool combine_consts;
2665
2666 if (*n_subexprs > 3) {
2667 hist_err(tr: file->tr, err_type: HIST_ERR_TOO_MANY_SUBEXPR, err_pos: errpos(str));
2668 return ERR_PTR(error: -EINVAL);
2669 }
2670
2671 field_op = contains_operator(str, sep: &sep);
2672
2673 if (field_op == FIELD_OP_NONE)
2674 return parse_atom(hist_data, file, str, flags: &flags, var_name);
2675
2676 if (field_op == FIELD_OP_UNARY_MINUS)
2677 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs);
2678
2679 /* Binary operator found, increment n_subexprs */
2680 ++*n_subexprs;
2681
2682 /* Split the expression string at the root operator */
2683 if (!sep)
2684 return ERR_PTR(error: -EINVAL);
2685
2686 *sep = '\0';
2687 operand1_str = str;
2688 str = sep+1;
2689
2690 /* Binary operator requires both operands */
2691 if (*operand1_str == '\0' || *str == '\0')
2692 return ERR_PTR(error: -EINVAL);
2693
2694 operand_flags = 0;
2695
2696 /* LHS of string is an expression e.g. a+b in a+b+c */
2697 operand1 = parse_expr(hist_data, file, str: operand1_str, flags: operand_flags, NULL, n_subexprs);
2698 if (IS_ERR(ptr: operand1))
2699 return ERR_CAST(ptr: operand1);
2700
2701 if (operand1->flags & HIST_FIELD_FL_STRING) {
2702 hist_err(tr: file->tr, err_type: HIST_ERR_INVALID_STR_OPERAND, err_pos: errpos(str: operand1_str));
2703 ret = -EINVAL;
2704 goto free_op1;
2705 }
2706
2707 /* RHS of string is another expression e.g. c in a+b+c */
2708 operand_flags = 0;
2709 operand2 = parse_expr(hist_data, file, str, flags: operand_flags, NULL, n_subexprs);
2710 if (IS_ERR(ptr: operand2)) {
2711 ret = PTR_ERR(ptr: operand2);
2712 goto free_op1;
2713 }
2714 if (operand2->flags & HIST_FIELD_FL_STRING) {
2715 hist_err(tr: file->tr, err_type: HIST_ERR_INVALID_STR_OPERAND, err_pos: errpos(str));
2716 ret = -EINVAL;
2717 goto free_operands;
2718 }
2719
2720 switch (field_op) {
2721 case FIELD_OP_MINUS:
2722 op_fn = HIST_FIELD_FN_MINUS;
2723 break;
2724 case FIELD_OP_PLUS:
2725 op_fn = HIST_FIELD_FN_PLUS;
2726 break;
2727 case FIELD_OP_DIV:
2728 op_fn = HIST_FIELD_FN_DIV;
2729 break;
2730 case FIELD_OP_MULT:
2731 op_fn = HIST_FIELD_FN_MULT;
2732 break;
2733 default:
2734 ret = -EINVAL;
2735 goto free_operands;
2736 }
2737
2738 ret = check_expr_operands(tr: file->tr, operand1, operand2, var1: &var1, var2: &var2);
2739 if (ret)
2740 goto free_operands;
2741
2742 operand_flags = var1 ? var1->flags : operand1->flags;
2743 operand2_flags = var2 ? var2->flags : operand2->flags;
2744
2745 /*
2746 * If both operands are constant, the expression can be
2747 * collapsed to a single constant.
2748 */
2749 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST;
2750
2751 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR;
2752
2753 flags |= operand1->flags &
2754 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2755
2756 expr = create_hist_field(hist_data, NULL, flags, var_name);
2757 if (!expr) {
2758 ret = -ENOMEM;
2759 goto free_operands;
2760 }
2761
2762 operand1->read_once = true;
2763 operand2->read_once = true;
2764
2765 /* The operands are now owned and free'd by 'expr' */
2766 expr->operands[0] = operand1;
2767 expr->operands[1] = operand2;
2768
2769 if (field_op == FIELD_OP_DIV &&
2770 operand2_flags & HIST_FIELD_FL_CONST) {
2771 u64 divisor = var2 ? var2->constant : operand2->constant;
2772
2773 if (!divisor) {
2774 hist_err(tr: file->tr, err_type: HIST_ERR_DIVISION_BY_ZERO, err_pos: errpos(str));
2775 ret = -EDOM;
2776 goto free_expr;
2777 }
2778
2779 /*
2780 * Copy the divisor here so we don't have to look it up
2781 * later if this is a var ref
2782 */
2783 operand2->constant = divisor;
2784 op_fn = hist_field_get_div_fn(divisor: operand2);
2785 }
2786
2787 expr->fn_num = op_fn;
2788
2789 if (combine_consts) {
2790 if (var1)
2791 expr->operands[0] = var1;
2792 if (var2)
2793 expr->operands[1] = var2;
2794
2795 expr->constant = hist_fn_call(hist_field: expr, NULL, NULL, NULL, NULL);
2796 expr->fn_num = HIST_FIELD_FN_CONST;
2797
2798 expr->operands[0] = NULL;
2799 expr->operands[1] = NULL;
2800
2801 /*
2802 * var refs won't be destroyed immediately
2803 * See: destroy_hist_field()
2804 */
2805 destroy_hist_field(hist_field: operand2, level: 0);
2806 destroy_hist_field(hist_field: operand1, level: 0);
2807
2808 expr->name = expr_str(field: expr, level: 0);
2809 } else {
2810 /* The operand sizes should be the same, so just pick one */
2811 expr->size = operand1->size;
2812 expr->is_signed = operand1->is_signed;
2813
2814 expr->operator = field_op;
2815 expr->type = kstrdup_const(s: operand1->type, GFP_KERNEL);
2816 if (!expr->type) {
2817 ret = -ENOMEM;
2818 goto free_expr;
2819 }
2820
2821 expr->name = expr_str(field: expr, level: 0);
2822 }
2823
2824 return expr;
2825
2826free_operands:
2827 destroy_hist_field(hist_field: operand2, level: 0);
2828free_op1:
2829 destroy_hist_field(hist_field: operand1, level: 0);
2830 return ERR_PTR(error: ret);
2831
2832free_expr:
2833 destroy_hist_field(hist_field: expr, level: 0);
2834 return ERR_PTR(error: ret);
2835}
2836
2837static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2838 struct trace_event_file *file)
2839{
2840 struct event_trigger_data *test;
2841
2842 lockdep_assert_held(&event_mutex);
2843
2844 list_for_each_entry(test, &file->triggers, list) {
2845 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2846 if (test->private_data == hist_data)
2847 return test->filter_str;
2848 }
2849 }
2850
2851 return NULL;
2852}
2853
2854static struct event_command trigger_hist_cmd;
2855static int event_hist_trigger_parse(struct event_command *cmd_ops,
2856 struct trace_event_file *file,
2857 char *glob, char *cmd,
2858 char *param_and_filter);
2859
2860static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2861 struct hist_trigger_data *hist_data,
2862 unsigned int n_keys)
2863{
2864 struct hist_field *target_hist_field, *hist_field;
2865 unsigned int n, i, j;
2866
2867 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2868 return false;
2869
2870 i = hist_data->n_vals;
2871 j = target_hist_data->n_vals;
2872
2873 for (n = 0; n < n_keys; n++) {
2874 hist_field = hist_data->fields[i + n];
2875 target_hist_field = target_hist_data->fields[j + n];
2876
2877 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2878 return false;
2879 if (hist_field->size != target_hist_field->size)
2880 return false;
2881 if (hist_field->is_signed != target_hist_field->is_signed)
2882 return false;
2883 }
2884
2885 return true;
2886}
2887
2888static struct hist_trigger_data *
2889find_compatible_hist(struct hist_trigger_data *target_hist_data,
2890 struct trace_event_file *file)
2891{
2892 struct hist_trigger_data *hist_data;
2893 struct event_trigger_data *test;
2894 unsigned int n_keys;
2895
2896 lockdep_assert_held(&event_mutex);
2897
2898 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2899
2900 list_for_each_entry(test, &file->triggers, list) {
2901 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2902 hist_data = test->private_data;
2903
2904 if (compatible_keys(target_hist_data, hist_data, n_keys))
2905 return hist_data;
2906 }
2907 }
2908
2909 return NULL;
2910}
2911
2912static struct trace_event_file *event_file(struct trace_array *tr,
2913 char *system, char *event_name)
2914{
2915 struct trace_event_file *file;
2916
2917 file = __find_event_file(tr, system, event: event_name);
2918 if (!file)
2919 return ERR_PTR(error: -EINVAL);
2920
2921 return file;
2922}
2923
2924static struct hist_field *
2925find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2926 char *system, char *event_name, char *field_name)
2927{
2928 struct hist_field *event_var;
2929 char *synthetic_name;
2930
2931 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2932 if (!synthetic_name)
2933 return ERR_PTR(error: -ENOMEM);
2934
2935 strcpy(p: synthetic_name, q: "synthetic_");
2936 strcat(p: synthetic_name, q: field_name);
2937
2938 event_var = find_event_var(hist_data: target_hist_data, system, event_name, var_name: synthetic_name);
2939
2940 kfree(objp: synthetic_name);
2941
2942 return event_var;
2943}
2944
2945/**
2946 * create_field_var_hist - Automatically create a histogram and var for a field
2947 * @target_hist_data: The target hist trigger
2948 * @subsys_name: Optional subsystem name
2949 * @event_name: Optional event name
2950 * @field_name: The name of the field (and the resulting variable)
2951 *
2952 * Hist trigger actions fetch data from variables, not directly from
2953 * events. However, for convenience, users are allowed to directly
2954 * specify an event field in an action, which will be automatically
2955 * converted into a variable on their behalf.
2956 *
2957 * If a user specifies a field on an event that isn't the event the
2958 * histogram currently being defined (the target event histogram), the
2959 * only way that can be accomplished is if a new hist trigger is
2960 * created and the field variable defined on that.
2961 *
2962 * This function creates a new histogram compatible with the target
2963 * event (meaning a histogram with the same key as the target
2964 * histogram), and creates a variable for the specified field, but
2965 * with 'synthetic_' prepended to the variable name in order to avoid
2966 * collision with normal field variables.
2967 *
2968 * Return: The variable created for the field.
2969 */
2970static struct hist_field *
2971create_field_var_hist(struct hist_trigger_data *target_hist_data,
2972 char *subsys_name, char *event_name, char *field_name)
2973{
2974 struct trace_array *tr = target_hist_data->event_file->tr;
2975 struct hist_trigger_data *hist_data;
2976 unsigned int i, n, first = true;
2977 struct field_var_hist *var_hist;
2978 struct trace_event_file *file;
2979 struct hist_field *key_field;
2980 struct hist_field *event_var;
2981 char *saved_filter;
2982 char *cmd;
2983 int ret;
2984
2985 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2986 hist_err(tr, err_type: HIST_ERR_TOO_MANY_FIELD_VARS, err_pos: errpos(str: field_name));
2987 return ERR_PTR(error: -EINVAL);
2988 }
2989
2990 file = event_file(tr, system: subsys_name, event_name);
2991
2992 if (IS_ERR(ptr: file)) {
2993 hist_err(tr, err_type: HIST_ERR_EVENT_FILE_NOT_FOUND, err_pos: errpos(str: field_name));
2994 ret = PTR_ERR(ptr: file);
2995 return ERR_PTR(error: ret);
2996 }
2997
2998 /*
2999 * Look for a histogram compatible with target. We'll use the
3000 * found histogram specification to create a new matching
3001 * histogram with our variable on it. target_hist_data is not
3002 * yet a registered histogram so we can't use that.
3003 */
3004 hist_data = find_compatible_hist(target_hist_data, file);
3005 if (!hist_data) {
3006 hist_err(tr, err_type: HIST_ERR_HIST_NOT_FOUND, err_pos: errpos(str: field_name));
3007 return ERR_PTR(error: -EINVAL);
3008 }
3009
3010 /* See if a synthetic field variable has already been created */
3011 event_var = find_synthetic_field_var(target_hist_data, system: subsys_name,
3012 event_name, field_name);
3013 if (!IS_ERR_OR_NULL(ptr: event_var))
3014 return event_var;
3015
3016 var_hist = kzalloc(size: sizeof(*var_hist), GFP_KERNEL);
3017 if (!var_hist)
3018 return ERR_PTR(error: -ENOMEM);
3019
3020 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
3021 if (!cmd) {
3022 kfree(objp: var_hist);
3023 return ERR_PTR(error: -ENOMEM);
3024 }
3025
3026 /* Use the same keys as the compatible histogram */
3027 strcat(p: cmd, q: "keys=");
3028
3029 for_each_hist_key_field(i, hist_data) {
3030 key_field = hist_data->fields[i];
3031 if (!first)
3032 strcat(p: cmd, q: ",");
3033 strcat(p: cmd, q: key_field->field->name);
3034 first = false;
3035 }
3036
3037 /* Create the synthetic field variable specification */
3038 strcat(p: cmd, q: ":synthetic_");
3039 strcat(p: cmd, q: field_name);
3040 strcat(p: cmd, q: "=");
3041 strcat(p: cmd, q: field_name);
3042
3043 /* Use the same filter as the compatible histogram */
3044 saved_filter = find_trigger_filter(hist_data, file);
3045 if (saved_filter) {
3046 strcat(p: cmd, q: " if ");
3047 strcat(p: cmd, q: saved_filter);
3048 }
3049
3050 var_hist->cmd = kstrdup(s: cmd, GFP_KERNEL);
3051 if (!var_hist->cmd) {
3052 kfree(objp: cmd);
3053 kfree(objp: var_hist);
3054 return ERR_PTR(error: -ENOMEM);
3055 }
3056
3057 /* Save the compatible histogram information */
3058 var_hist->hist_data = hist_data;
3059
3060 /* Create the new histogram with our variable */
3061 ret = event_hist_trigger_parse(cmd_ops: &trigger_hist_cmd, file,
3062 glob: "", cmd: "hist", param_and_filter: cmd);
3063 if (ret) {
3064 kfree(objp: cmd);
3065 kfree(objp: var_hist->cmd);
3066 kfree(objp: var_hist);
3067 hist_err(tr, err_type: HIST_ERR_HIST_CREATE_FAIL, err_pos: errpos(str: field_name));
3068 return ERR_PTR(error: ret);
3069 }
3070
3071 kfree(objp: cmd);
3072
3073 /* If we can't find the variable, something went wrong */
3074 event_var = find_synthetic_field_var(target_hist_data, system: subsys_name,
3075 event_name, field_name);
3076 if (IS_ERR_OR_NULL(ptr: event_var)) {
3077 kfree(objp: var_hist->cmd);
3078 kfree(objp: var_hist);
3079 hist_err(tr, err_type: HIST_ERR_SYNTH_VAR_NOT_FOUND, err_pos: errpos(str: field_name));
3080 return ERR_PTR(error: -EINVAL);
3081 }
3082
3083 n = target_hist_data->n_field_var_hists;
3084 target_hist_data->field_var_hists[n] = var_hist;
3085 target_hist_data->n_field_var_hists++;
3086
3087 return event_var;
3088}
3089
3090static struct hist_field *
3091find_target_event_var(struct hist_trigger_data *hist_data,
3092 char *subsys_name, char *event_name, char *var_name)
3093{
3094 struct trace_event_file *file = hist_data->event_file;
3095 struct hist_field *hist_field = NULL;
3096
3097 if (subsys_name) {
3098 struct trace_event_call *call;
3099
3100 if (!event_name)
3101 return NULL;
3102
3103 call = file->event_call;
3104
3105 if (strcmp(subsys_name, call->class->system) != 0)
3106 return NULL;
3107
3108 if (strcmp(event_name, trace_event_name(call)) != 0)
3109 return NULL;
3110 }
3111
3112 hist_field = find_var_field(hist_data, var_name);
3113
3114 return hist_field;
3115}
3116
3117static inline void __update_field_vars(struct tracing_map_elt *elt,
3118 struct trace_buffer *buffer,
3119 struct ring_buffer_event *rbe,
3120 void *rec,
3121 struct field_var **field_vars,
3122 unsigned int n_field_vars,
3123 unsigned int field_var_str_start)
3124{
3125 struct hist_elt_data *elt_data = elt->private_data;
3126 unsigned int i, j, var_idx;
3127 u64 var_val;
3128
3129 /* Make sure stacktrace can fit in the string variable length */
3130 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX);
3131
3132 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3133 struct field_var *field_var = field_vars[i];
3134 struct hist_field *var = field_var->var;
3135 struct hist_field *val = field_var->val;
3136
3137 var_val = hist_fn_call(hist_field: val, elt, buffer, rbe, event: rec);
3138 var_idx = var->var.idx;
3139
3140 if (val->flags & (HIST_FIELD_FL_STRING |
3141 HIST_FIELD_FL_STACKTRACE)) {
3142 char *str = elt_data->field_var_str[j++];
3143 char *val_str = (char *)(uintptr_t)var_val;
3144 unsigned int size;
3145
3146 if (val->flags & HIST_FIELD_FL_STRING) {
3147 size = min(val->size, STR_VAR_LEN_MAX);
3148 strscpy(p: str, q: val_str, size);
3149 } else {
3150 char *stack_start = str + sizeof(unsigned long);
3151 int e;
3152
3153 e = stack_trace_save(store: (void *)stack_start,
3154 HIST_STACKTRACE_DEPTH,
3155 HIST_STACKTRACE_SKIP);
3156 if (e < HIST_STACKTRACE_DEPTH - 1)
3157 ((unsigned long *)stack_start)[e] = 0;
3158 *((unsigned long *)str) = e;
3159 }
3160 var_val = (u64)(uintptr_t)str;
3161 }
3162 tracing_map_set_var(elt, i: var_idx, n: var_val);
3163 }
3164}
3165
3166static void update_field_vars(struct hist_trigger_data *hist_data,
3167 struct tracing_map_elt *elt,
3168 struct trace_buffer *buffer,
3169 struct ring_buffer_event *rbe,
3170 void *rec)
3171{
3172 __update_field_vars(elt, buffer, rbe, rec, field_vars: hist_data->field_vars,
3173 n_field_vars: hist_data->n_field_vars, field_var_str_start: 0);
3174}
3175
3176static void save_track_data_vars(struct hist_trigger_data *hist_data,
3177 struct tracing_map_elt *elt,
3178 struct trace_buffer *buffer, void *rec,
3179 struct ring_buffer_event *rbe, void *key,
3180 struct action_data *data, u64 *var_ref_vals)
3181{
3182 __update_field_vars(elt, buffer, rbe, rec, field_vars: hist_data->save_vars,
3183 n_field_vars: hist_data->n_save_vars, field_var_str_start: hist_data->n_field_var_str);
3184}
3185
3186static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3187 struct trace_event_file *file,
3188 char *name, int size, const char *type)
3189{
3190 struct hist_field *var;
3191 int idx;
3192
3193 if (find_var(hist_data, file, var_name: name) && !hist_data->remove) {
3194 var = ERR_PTR(error: -EINVAL);
3195 goto out;
3196 }
3197
3198 var = kzalloc(size: sizeof(struct hist_field), GFP_KERNEL);
3199 if (!var) {
3200 var = ERR_PTR(error: -ENOMEM);
3201 goto out;
3202 }
3203
3204 idx = tracing_map_add_var(map: hist_data->map);
3205 if (idx < 0) {
3206 kfree(objp: var);
3207 var = ERR_PTR(error: -EINVAL);
3208 goto out;
3209 }
3210
3211 var->ref = 1;
3212 var->flags = HIST_FIELD_FL_VAR;
3213 var->var.idx = idx;
3214 var->var.hist_data = var->hist_data = hist_data;
3215 var->size = size;
3216 var->var.name = kstrdup(s: name, GFP_KERNEL);
3217 var->type = kstrdup_const(s: type, GFP_KERNEL);
3218 if (!var->var.name || !var->type) {
3219 kfree_const(x: var->type);
3220 kfree(objp: var->var.name);
3221 kfree(objp: var);
3222 var = ERR_PTR(error: -ENOMEM);
3223 }
3224 out:
3225 return var;
3226}
3227
3228static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3229 struct trace_event_file *file,
3230 char *field_name)
3231{
3232 struct hist_field *val = NULL, *var = NULL;
3233 unsigned long flags = HIST_FIELD_FL_VAR;
3234 struct trace_array *tr = file->tr;
3235 struct field_var *field_var;
3236 int ret = 0;
3237
3238 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3239 hist_err(tr, err_type: HIST_ERR_TOO_MANY_FIELD_VARS, err_pos: errpos(str: field_name));
3240 ret = -EINVAL;
3241 goto err;
3242 }
3243
3244 val = parse_atom(hist_data, file, str: field_name, flags: &flags, NULL);
3245 if (IS_ERR(ptr: val)) {
3246 hist_err(tr, err_type: HIST_ERR_FIELD_VAR_PARSE_FAIL, err_pos: errpos(str: field_name));
3247 ret = PTR_ERR(ptr: val);
3248 goto err;
3249 }
3250
3251 var = create_var(hist_data, file, name: field_name, size: val->size, type: val->type);
3252 if (IS_ERR(ptr: var)) {
3253 hist_err(tr, err_type: HIST_ERR_VAR_CREATE_FIND_FAIL, err_pos: errpos(str: field_name));
3254 kfree(objp: val);
3255 ret = PTR_ERR(ptr: var);
3256 goto err;
3257 }
3258
3259 field_var = kzalloc(size: sizeof(struct field_var), GFP_KERNEL);
3260 if (!field_var) {
3261 kfree(objp: val);
3262 kfree(objp: var);
3263 ret = -ENOMEM;
3264 goto err;
3265 }
3266
3267 field_var->var = var;
3268 field_var->val = val;
3269 out:
3270 return field_var;
3271 err:
3272 field_var = ERR_PTR(error: ret);
3273 goto out;
3274}
3275
3276/**
3277 * create_target_field_var - Automatically create a variable for a field
3278 * @target_hist_data: The target hist trigger
3279 * @subsys_name: Optional subsystem name
3280 * @event_name: Optional event name
3281 * @var_name: The name of the field (and the resulting variable)
3282 *
3283 * Hist trigger actions fetch data from variables, not directly from
3284 * events. However, for convenience, users are allowed to directly
3285 * specify an event field in an action, which will be automatically
3286 * converted into a variable on their behalf.
3287 *
3288 * This function creates a field variable with the name var_name on
3289 * the hist trigger currently being defined on the target event. If
3290 * subsys_name and event_name are specified, this function simply
3291 * verifies that they do in fact match the target event subsystem and
3292 * event name.
3293 *
3294 * Return: The variable created for the field.
3295 */
3296static struct field_var *
3297create_target_field_var(struct hist_trigger_data *target_hist_data,
3298 char *subsys_name, char *event_name, char *var_name)
3299{
3300 struct trace_event_file *file = target_hist_data->event_file;
3301
3302 if (subsys_name) {
3303 struct trace_event_call *call;
3304
3305 if (!event_name)
3306 return NULL;
3307
3308 call = file->event_call;
3309
3310 if (strcmp(subsys_name, call->class->system) != 0)
3311 return NULL;
3312
3313 if (strcmp(event_name, trace_event_name(call)) != 0)
3314 return NULL;
3315 }
3316
3317 return create_field_var(hist_data: target_hist_data, file, field_name: var_name);
3318}
3319
3320static bool check_track_val_max(u64 track_val, u64 var_val)
3321{
3322 if (var_val <= track_val)
3323 return false;
3324
3325 return true;
3326}
3327
3328static bool check_track_val_changed(u64 track_val, u64 var_val)
3329{
3330 if (var_val == track_val)
3331 return false;
3332
3333 return true;
3334}
3335
3336static u64 get_track_val(struct hist_trigger_data *hist_data,
3337 struct tracing_map_elt *elt,
3338 struct action_data *data)
3339{
3340 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3341 u64 track_val;
3342
3343 track_val = tracing_map_read_var(elt, i: track_var_idx);
3344
3345 return track_val;
3346}
3347
3348static void save_track_val(struct hist_trigger_data *hist_data,
3349 struct tracing_map_elt *elt,
3350 struct action_data *data, u64 var_val)
3351{
3352 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3353
3354 tracing_map_set_var(elt, i: track_var_idx, n: var_val);
3355}
3356
3357static void save_track_data(struct hist_trigger_data *hist_data,
3358 struct tracing_map_elt *elt,
3359 struct trace_buffer *buffer, void *rec,
3360 struct ring_buffer_event *rbe, void *key,
3361 struct action_data *data, u64 *var_ref_vals)
3362{
3363 if (data->track_data.save_data)
3364 data->track_data.save_data(hist_data, elt, buffer, rec, rbe,
3365 key, data, var_ref_vals);
3366}
3367
3368static bool check_track_val(struct tracing_map_elt *elt,
3369 struct action_data *data,
3370 u64 var_val)
3371{
3372 struct hist_trigger_data *hist_data;
3373 u64 track_val;
3374
3375 hist_data = data->track_data.track_var->hist_data;
3376 track_val = get_track_val(hist_data, elt, data);
3377
3378 return data->track_data.check_val(track_val, var_val);
3379}
3380
3381#ifdef CONFIG_TRACER_SNAPSHOT
3382static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3383{
3384 /* called with tr->max_lock held */
3385 struct track_data *track_data = tr->cond_snapshot->cond_data;
3386 struct hist_elt_data *elt_data, *track_elt_data;
3387 struct snapshot_context *context = cond_data;
3388 struct action_data *action;
3389 u64 track_val;
3390
3391 if (!track_data)
3392 return false;
3393
3394 action = track_data->action_data;
3395
3396 track_val = get_track_val(hist_data: track_data->hist_data, elt: context->elt,
3397 data: track_data->action_data);
3398
3399 if (!action->track_data.check_val(track_data->track_val, track_val))
3400 return false;
3401
3402 track_data->track_val = track_val;
3403 memcpy(track_data->key, context->key, track_data->key_len);
3404
3405 elt_data = context->elt->private_data;
3406 track_elt_data = track_data->elt.private_data;
3407 if (elt_data->comm)
3408 strncpy(p: track_elt_data->comm, q: elt_data->comm, size: TASK_COMM_LEN);
3409
3410 track_data->updated = true;
3411
3412 return true;
3413}
3414
3415static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3416 struct tracing_map_elt *elt,
3417 struct trace_buffer *buffer, void *rec,
3418 struct ring_buffer_event *rbe, void *key,
3419 struct action_data *data,
3420 u64 *var_ref_vals)
3421{
3422 struct trace_event_file *file = hist_data->event_file;
3423 struct snapshot_context context;
3424
3425 context.elt = elt;
3426 context.key = key;
3427
3428 tracing_snapshot_cond(tr: file->tr, cond_data: &context);
3429}
3430
3431static void hist_trigger_print_key(struct seq_file *m,
3432 struct hist_trigger_data *hist_data,
3433 void *key,
3434 struct tracing_map_elt *elt);
3435
3436static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
3437{
3438 unsigned int i;
3439
3440 if (!hist_data->n_actions)
3441 return NULL;
3442
3443 for (i = 0; i < hist_data->n_actions; i++) {
3444 struct action_data *data = hist_data->actions[i];
3445
3446 if (data->action == ACTION_SNAPSHOT)
3447 return data;
3448 }
3449
3450 return NULL;
3451}
3452
3453static void track_data_snapshot_print(struct seq_file *m,
3454 struct hist_trigger_data *hist_data)
3455{
3456 struct trace_event_file *file = hist_data->event_file;
3457 struct track_data *track_data;
3458 struct action_data *action;
3459
3460 track_data = tracing_cond_snapshot_data(tr: file->tr);
3461 if (!track_data)
3462 return;
3463
3464 if (!track_data->updated)
3465 return;
3466
3467 action = snapshot_action(hist_data);
3468 if (!action)
3469 return;
3470
3471 seq_puts(m, s: "\nSnapshot taken (see tracing/snapshot). Details:\n");
3472 seq_printf(m, fmt: "\ttriggering value { %s(%s) }: %10llu",
3473 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
3474 action->track_data.var_str, track_data->track_val);
3475
3476 seq_puts(m, s: "\ttriggered by event with key: ");
3477 hist_trigger_print_key(m, hist_data, key: track_data->key, elt: &track_data->elt);
3478 seq_putc(m, c: '\n');
3479}
3480#else
3481static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3482{
3483 return false;
3484}
3485static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3486 struct tracing_map_elt *elt,
3487 struct trace_buffer *buffer, void *rec,
3488 struct ring_buffer_event *rbe, void *key,
3489 struct action_data *data,
3490 u64 *var_ref_vals) {}
3491static void track_data_snapshot_print(struct seq_file *m,
3492 struct hist_trigger_data *hist_data) {}
3493#endif /* CONFIG_TRACER_SNAPSHOT */
3494
3495static void track_data_print(struct seq_file *m,
3496 struct hist_trigger_data *hist_data,
3497 struct tracing_map_elt *elt,
3498 struct action_data *data)
3499{
3500 u64 track_val = get_track_val(hist_data, elt, data);
3501 unsigned int i, save_var_idx;
3502
3503 if (data->handler == HANDLER_ONMAX)
3504 seq_printf(m, fmt: "\n\tmax: %10llu", track_val);
3505 else if (data->handler == HANDLER_ONCHANGE)
3506 seq_printf(m, fmt: "\n\tchanged: %10llu", track_val);
3507
3508 if (data->action == ACTION_SNAPSHOT)
3509 return;
3510
3511 for (i = 0; i < hist_data->n_save_vars; i++) {
3512 struct hist_field *save_val = hist_data->save_vars[i]->val;
3513 struct hist_field *save_var = hist_data->save_vars[i]->var;
3514 u64 val;
3515
3516 save_var_idx = save_var->var.idx;
3517
3518 val = tracing_map_read_var(elt, i: save_var_idx);
3519
3520 if (save_val->flags & HIST_FIELD_FL_STRING) {
3521 seq_printf(m, fmt: " %s: %-32s", save_var->var.name,
3522 (char *)(uintptr_t)(val));
3523 } else
3524 seq_printf(m, fmt: " %s: %10llu", save_var->var.name, val);
3525 }
3526}
3527
3528static void ontrack_action(struct hist_trigger_data *hist_data,
3529 struct tracing_map_elt *elt,
3530 struct trace_buffer *buffer, void *rec,
3531 struct ring_buffer_event *rbe, void *key,
3532 struct action_data *data, u64 *var_ref_vals)
3533{
3534 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
3535
3536 if (check_track_val(elt, data, var_val)) {
3537 save_track_val(hist_data, elt, data, var_val);
3538 save_track_data(hist_data, elt, buffer, rec, rbe,
3539 key, data, var_ref_vals);
3540 }
3541}
3542
3543static void action_data_destroy(struct action_data *data)
3544{
3545 unsigned int i;
3546
3547 lockdep_assert_held(&event_mutex);
3548
3549 kfree(objp: data->action_name);
3550
3551 for (i = 0; i < data->n_params; i++)
3552 kfree(objp: data->params[i]);
3553
3554 if (data->synth_event)
3555 data->synth_event->ref--;
3556
3557 kfree(objp: data->synth_event_name);
3558
3559 kfree(objp: data);
3560}
3561
3562static void track_data_destroy(struct hist_trigger_data *hist_data,
3563 struct action_data *data)
3564{
3565 struct trace_event_file *file = hist_data->event_file;
3566
3567 destroy_hist_field(hist_field: data->track_data.track_var, level: 0);
3568
3569 if (data->action == ACTION_SNAPSHOT) {
3570 struct track_data *track_data;
3571
3572 track_data = tracing_cond_snapshot_data(tr: file->tr);
3573 if (track_data && track_data->hist_data == hist_data) {
3574 tracing_snapshot_cond_disable(tr: file->tr);
3575 track_data_free(track_data);
3576 }
3577 }
3578
3579 kfree(objp: data->track_data.var_str);
3580
3581 action_data_destroy(data);
3582}
3583
3584static int action_create(struct hist_trigger_data *hist_data,
3585 struct action_data *data);
3586
3587static int track_data_create(struct hist_trigger_data *hist_data,
3588 struct action_data *data)
3589{
3590 struct hist_field *var_field, *ref_field, *track_var = NULL;
3591 struct trace_event_file *file = hist_data->event_file;
3592 struct trace_array *tr = file->tr;
3593 char *track_data_var_str;
3594 int ret = 0;
3595
3596 track_data_var_str = data->track_data.var_str;
3597 if (track_data_var_str[0] != '$') {
3598 hist_err(tr, err_type: HIST_ERR_ONX_NOT_VAR, err_pos: errpos(str: track_data_var_str));
3599 return -EINVAL;
3600 }
3601 track_data_var_str++;
3602
3603 var_field = find_target_event_var(hist_data, NULL, NULL, var_name: track_data_var_str);
3604 if (!var_field) {
3605 hist_err(tr, err_type: HIST_ERR_ONX_VAR_NOT_FOUND, err_pos: errpos(str: track_data_var_str));
3606 return -EINVAL;
3607 }
3608
3609 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3610 if (!ref_field)
3611 return -ENOMEM;
3612
3613 data->track_data.var_ref = ref_field;
3614
3615 if (data->handler == HANDLER_ONMAX)
3616 track_var = create_var(hist_data, file, name: "__max", size: sizeof(u64), type: "u64");
3617 if (IS_ERR(ptr: track_var)) {
3618 hist_err(tr, err_type: HIST_ERR_ONX_VAR_CREATE_FAIL, err_pos: 0);
3619 ret = PTR_ERR(ptr: track_var);
3620 goto out;
3621 }
3622
3623 if (data->handler == HANDLER_ONCHANGE)
3624 track_var = create_var(hist_data, file, name: "__change", size: sizeof(u64), type: "u64");
3625 if (IS_ERR(ptr: track_var)) {
3626 hist_err(tr, err_type: HIST_ERR_ONX_VAR_CREATE_FAIL, err_pos: 0);
3627 ret = PTR_ERR(ptr: track_var);
3628 goto out;
3629 }
3630 data->track_data.track_var = track_var;
3631
3632 ret = action_create(hist_data, data);
3633 out:
3634 return ret;
3635}
3636
3637static int parse_action_params(struct trace_array *tr, char *params,
3638 struct action_data *data)
3639{
3640 char *param, *saved_param;
3641 bool first_param = true;
3642 int ret = 0;
3643
3644 while (params) {
3645 if (data->n_params >= SYNTH_FIELDS_MAX) {
3646 hist_err(tr, err_type: HIST_ERR_TOO_MANY_PARAMS, err_pos: 0);
3647 ret = -EINVAL;
3648 goto out;
3649 }
3650
3651 param = strsep(&params, ",");
3652 if (!param) {
3653 hist_err(tr, err_type: HIST_ERR_PARAM_NOT_FOUND, err_pos: 0);
3654 ret = -EINVAL;
3655 goto out;
3656 }
3657
3658 param = strstrip(str: param);
3659 if (strlen(param) < 2) {
3660 hist_err(tr, err_type: HIST_ERR_INVALID_PARAM, err_pos: errpos(str: param));
3661 ret = -EINVAL;
3662 goto out;
3663 }
3664
3665 saved_param = kstrdup(s: param, GFP_KERNEL);
3666 if (!saved_param) {
3667 ret = -ENOMEM;
3668 goto out;
3669 }
3670
3671 if (first_param && data->use_trace_keyword) {
3672 data->synth_event_name = saved_param;
3673 first_param = false;
3674 continue;
3675 }
3676 first_param = false;
3677
3678 data->params[data->n_params++] = saved_param;
3679 }
3680 out:
3681 return ret;
3682}
3683
3684static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3685 enum handler_id handler)
3686{
3687 char *action_name;
3688 int ret = 0;
3689
3690 strsep(&str, ".");
3691 if (!str) {
3692 hist_err(tr, err_type: HIST_ERR_ACTION_NOT_FOUND, err_pos: 0);
3693 ret = -EINVAL;
3694 goto out;
3695 }
3696
3697 action_name = strsep(&str, "(");
3698 if (!action_name || !str) {
3699 hist_err(tr, err_type: HIST_ERR_ACTION_NOT_FOUND, err_pos: 0);
3700 ret = -EINVAL;
3701 goto out;
3702 }
3703
3704 if (str_has_prefix(str: action_name, prefix: "save")) {
3705 char *params = strsep(&str, ")");
3706
3707 if (!params) {
3708 hist_err(tr, err_type: HIST_ERR_NO_SAVE_PARAMS, err_pos: 0);
3709 ret = -EINVAL;
3710 goto out;
3711 }
3712
3713 ret = parse_action_params(tr, params, data);
3714 if (ret)
3715 goto out;
3716
3717 if (handler == HANDLER_ONMAX)
3718 data->track_data.check_val = check_track_val_max;
3719 else if (handler == HANDLER_ONCHANGE)
3720 data->track_data.check_val = check_track_val_changed;
3721 else {
3722 hist_err(tr, err_type: HIST_ERR_ACTION_MISMATCH, err_pos: errpos(str: action_name));
3723 ret = -EINVAL;
3724 goto out;
3725 }
3726
3727 data->track_data.save_data = save_track_data_vars;
3728 data->fn = ontrack_action;
3729 data->action = ACTION_SAVE;
3730 } else if (str_has_prefix(str: action_name, prefix: "snapshot")) {
3731 char *params = strsep(&str, ")");
3732
3733 if (!str) {
3734 hist_err(tr, err_type: HIST_ERR_NO_CLOSING_PAREN, err_pos: errpos(str: params));
3735 ret = -EINVAL;
3736 goto out;
3737 }
3738
3739 if (handler == HANDLER_ONMAX)
3740 data->track_data.check_val = check_track_val_max;
3741 else if (handler == HANDLER_ONCHANGE)
3742 data->track_data.check_val = check_track_val_changed;
3743 else {
3744 hist_err(tr, err_type: HIST_ERR_ACTION_MISMATCH, err_pos: errpos(str: action_name));
3745 ret = -EINVAL;
3746 goto out;
3747 }
3748
3749 data->track_data.save_data = save_track_data_snapshot;
3750 data->fn = ontrack_action;
3751 data->action = ACTION_SNAPSHOT;
3752 } else {
3753 char *params = strsep(&str, ")");
3754
3755 if (str_has_prefix(str: action_name, prefix: "trace"))
3756 data->use_trace_keyword = true;
3757
3758 if (params) {
3759 ret = parse_action_params(tr, params, data);
3760 if (ret)
3761 goto out;
3762 }
3763
3764 if (handler == HANDLER_ONMAX)
3765 data->track_data.check_val = check_track_val_max;
3766 else if (handler == HANDLER_ONCHANGE)
3767 data->track_data.check_val = check_track_val_changed;
3768
3769 if (handler != HANDLER_ONMATCH) {
3770 data->track_data.save_data = action_trace;
3771 data->fn = ontrack_action;
3772 } else
3773 data->fn = action_trace;
3774
3775 data->action = ACTION_TRACE;
3776 }
3777
3778 data->action_name = kstrdup(s: action_name, GFP_KERNEL);
3779 if (!data->action_name) {
3780 ret = -ENOMEM;
3781 goto out;
3782 }
3783
3784 data->handler = handler;
3785 out:
3786 return ret;
3787}
3788
3789static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3790 char *str, enum handler_id handler)
3791{
3792 struct action_data *data;
3793 int ret = -EINVAL;
3794 char *var_str;
3795
3796 data = kzalloc(size: sizeof(*data), GFP_KERNEL);
3797 if (!data)
3798 return ERR_PTR(error: -ENOMEM);
3799
3800 var_str = strsep(&str, ")");
3801 if (!var_str || !str) {
3802 ret = -EINVAL;
3803 goto free;
3804 }
3805
3806 data->track_data.var_str = kstrdup(s: var_str, GFP_KERNEL);
3807 if (!data->track_data.var_str) {
3808 ret = -ENOMEM;
3809 goto free;
3810 }
3811
3812 ret = action_parse(tr: hist_data->event_file->tr, str, data, handler);
3813 if (ret)
3814 goto free;
3815 out:
3816 return data;
3817 free:
3818 track_data_destroy(hist_data, data);
3819 data = ERR_PTR(error: ret);
3820 goto out;
3821}
3822
3823static void onmatch_destroy(struct action_data *data)
3824{
3825 kfree(objp: data->match_data.event);
3826 kfree(objp: data->match_data.event_system);
3827
3828 action_data_destroy(data);
3829}
3830
3831static void destroy_field_var(struct field_var *field_var)
3832{
3833 if (!field_var)
3834 return;
3835
3836 destroy_hist_field(hist_field: field_var->var, level: 0);
3837 destroy_hist_field(hist_field: field_var->val, level: 0);
3838
3839 kfree(objp: field_var);
3840}
3841
3842static void destroy_field_vars(struct hist_trigger_data *hist_data)
3843{
3844 unsigned int i;
3845
3846 for (i = 0; i < hist_data->n_field_vars; i++)
3847 destroy_field_var(field_var: hist_data->field_vars[i]);
3848
3849 for (i = 0; i < hist_data->n_save_vars; i++)
3850 destroy_field_var(field_var: hist_data->save_vars[i]);
3851}
3852
3853static void save_field_var(struct hist_trigger_data *hist_data,
3854 struct field_var *field_var)
3855{
3856 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3857
3858 /* Stack traces are saved in the string storage too */
3859 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
3860 hist_data->n_field_var_str++;
3861}
3862
3863
3864static int check_synth_field(struct synth_event *event,
3865 struct hist_field *hist_field,
3866 unsigned int field_pos)
3867{
3868 struct synth_field *field;
3869
3870 if (field_pos >= event->n_fields)
3871 return -EINVAL;
3872
3873 field = event->fields[field_pos];
3874
3875 /*
3876 * A dynamic string synth field can accept static or
3877 * dynamic. A static string synth field can only accept a
3878 * same-sized static string, which is checked for later.
3879 */
3880 if (strstr(hist_field->type, "char[") && field->is_string
3881 && field->is_dynamic)
3882 return 0;
3883
3884 if (strstr(hist_field->type, "long[") && field->is_stack)
3885 return 0;
3886
3887 if (strcmp(field->type, hist_field->type) != 0) {
3888 if (field->size != hist_field->size ||
3889 (!field->is_string && field->is_signed != hist_field->is_signed))
3890 return -EINVAL;
3891 }
3892
3893 return 0;
3894}
3895
3896static struct hist_field *
3897trace_action_find_var(struct hist_trigger_data *hist_data,
3898 struct action_data *data,
3899 char *system, char *event, char *var)
3900{
3901 struct trace_array *tr = hist_data->event_file->tr;
3902 struct hist_field *hist_field;
3903
3904 var++; /* skip '$' */
3905
3906 hist_field = find_target_event_var(hist_data, subsys_name: system, event_name: event, var_name: var);
3907 if (!hist_field) {
3908 if (!system && data->handler == HANDLER_ONMATCH) {
3909 system = data->match_data.event_system;
3910 event = data->match_data.event;
3911 }
3912
3913 hist_field = find_event_var(hist_data, system, event_name: event, var_name: var);
3914 }
3915
3916 if (!hist_field)
3917 hist_err(tr, err_type: HIST_ERR_PARAM_NOT_FOUND, err_pos: errpos(str: var));
3918
3919 return hist_field;
3920}
3921
3922static struct hist_field *
3923trace_action_create_field_var(struct hist_trigger_data *hist_data,
3924 struct action_data *data, char *system,
3925 char *event, char *var)
3926{
3927 struct hist_field *hist_field = NULL;
3928 struct field_var *field_var;
3929
3930 /*
3931 * First try to create a field var on the target event (the
3932 * currently being defined). This will create a variable for
3933 * unqualified fields on the target event, or if qualified,
3934 * target fields that have qualified names matching the target.
3935 */
3936 field_var = create_target_field_var(target_hist_data: hist_data, subsys_name: system, event_name: event, var_name: var);
3937
3938 if (field_var && !IS_ERR(ptr: field_var)) {
3939 save_field_var(hist_data, field_var);
3940 hist_field = field_var->var;
3941 } else {
3942 field_var = NULL;
3943 /*
3944 * If no explicit system.event is specified, default to
3945 * looking for fields on the onmatch(system.event.xxx)
3946 * event.
3947 */
3948 if (!system && data->handler == HANDLER_ONMATCH) {
3949 system = data->match_data.event_system;
3950 event = data->match_data.event;
3951 }
3952
3953 if (!event)
3954 goto free;
3955 /*
3956 * At this point, we're looking at a field on another
3957 * event. Because we can't modify a hist trigger on
3958 * another event to add a variable for a field, we need
3959 * to create a new trigger on that event and create the
3960 * variable at the same time.
3961 */
3962 hist_field = create_field_var_hist(target_hist_data: hist_data, subsys_name: system, event_name: event, field_name: var);
3963 if (IS_ERR(ptr: hist_field))
3964 goto free;
3965 }
3966 out:
3967 return hist_field;
3968 free:
3969 destroy_field_var(field_var);
3970 hist_field = NULL;
3971 goto out;
3972}
3973
3974static int trace_action_create(struct hist_trigger_data *hist_data,
3975 struct action_data *data)
3976{
3977 struct trace_array *tr = hist_data->event_file->tr;
3978 char *event_name, *param, *system = NULL;
3979 struct hist_field *hist_field, *var_ref;
3980 unsigned int i;
3981 unsigned int field_pos = 0;
3982 struct synth_event *event;
3983 char *synth_event_name;
3984 int var_ref_idx, ret = 0;
3985
3986 lockdep_assert_held(&event_mutex);
3987
3988 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */
3989 if (data->n_params > SYNTH_FIELDS_MAX)
3990 return -EINVAL;
3991
3992 if (data->use_trace_keyword)
3993 synth_event_name = data->synth_event_name;
3994 else
3995 synth_event_name = data->action_name;
3996
3997 event = find_synth_event(name: synth_event_name);
3998 if (!event) {
3999 hist_err(tr, err_type: HIST_ERR_SYNTH_EVENT_NOT_FOUND, err_pos: errpos(str: synth_event_name));
4000 return -EINVAL;
4001 }
4002
4003 event->ref++;
4004
4005 for (i = 0; i < data->n_params; i++) {
4006 char *p;
4007
4008 p = param = kstrdup(s: data->params[i], GFP_KERNEL);
4009 if (!param) {
4010 ret = -ENOMEM;
4011 goto err;
4012 }
4013
4014 system = strsep(&param, ".");
4015 if (!param) {
4016 param = (char *)system;
4017 system = event_name = NULL;
4018 } else {
4019 event_name = strsep(&param, ".");
4020 if (!param) {
4021 kfree(objp: p);
4022 ret = -EINVAL;
4023 goto err;
4024 }
4025 }
4026
4027 if (param[0] == '$')
4028 hist_field = trace_action_find_var(hist_data, data,
4029 system, event: event_name,
4030 var: param);
4031 else
4032 hist_field = trace_action_create_field_var(hist_data,
4033 data,
4034 system,
4035 event: event_name,
4036 var: param);
4037
4038 if (!hist_field) {
4039 kfree(objp: p);
4040 ret = -EINVAL;
4041 goto err;
4042 }
4043
4044 if (check_synth_field(event, hist_field, field_pos) == 0) {
4045 var_ref = create_var_ref(hist_data, var_field: hist_field,
4046 system, event_name);
4047 if (!var_ref) {
4048 kfree(objp: p);
4049 ret = -ENOMEM;
4050 goto err;
4051 }
4052
4053 var_ref_idx = find_var_ref_idx(hist_data, var_field: var_ref);
4054 if (WARN_ON(var_ref_idx < 0)) {
4055 kfree(objp: p);
4056 ret = var_ref_idx;
4057 goto err;
4058 }
4059
4060 data->var_ref_idx[i] = var_ref_idx;
4061
4062 field_pos++;
4063 kfree(objp: p);
4064 continue;
4065 }
4066
4067 hist_err(tr, err_type: HIST_ERR_SYNTH_TYPE_MISMATCH, err_pos: errpos(str: param));
4068 kfree(objp: p);
4069 ret = -EINVAL;
4070 goto err;
4071 }
4072
4073 if (field_pos != event->n_fields) {
4074 hist_err(tr, err_type: HIST_ERR_SYNTH_COUNT_MISMATCH, err_pos: errpos(str: event->name));
4075 ret = -EINVAL;
4076 goto err;
4077 }
4078
4079 data->synth_event = event;
4080 out:
4081 return ret;
4082 err:
4083 event->ref--;
4084
4085 goto out;
4086}
4087
4088static int action_create(struct hist_trigger_data *hist_data,
4089 struct action_data *data)
4090{
4091 struct trace_event_file *file = hist_data->event_file;
4092 struct trace_array *tr = file->tr;
4093 struct track_data *track_data;
4094 struct field_var *field_var;
4095 unsigned int i;
4096 char *param;
4097 int ret = 0;
4098
4099 if (data->action == ACTION_TRACE)
4100 return trace_action_create(hist_data, data);
4101
4102 if (data->action == ACTION_SNAPSHOT) {
4103 track_data = track_data_alloc(key_len: hist_data->key_size, action_data: data, hist_data);
4104 if (IS_ERR(ptr: track_data)) {
4105 ret = PTR_ERR(ptr: track_data);
4106 goto out;
4107 }
4108
4109 ret = tracing_snapshot_cond_enable(tr: file->tr, cond_data: track_data,
4110 update: cond_snapshot_update);
4111 if (ret)
4112 track_data_free(track_data);
4113
4114 goto out;
4115 }
4116
4117 if (data->action == ACTION_SAVE) {
4118 if (hist_data->n_save_vars) {
4119 ret = -EEXIST;
4120 hist_err(tr, err_type: HIST_ERR_TOO_MANY_SAVE_ACTIONS, err_pos: 0);
4121 goto out;
4122 }
4123
4124 for (i = 0; i < data->n_params; i++) {
4125 param = kstrdup(s: data->params[i], GFP_KERNEL);
4126 if (!param) {
4127 ret = -ENOMEM;
4128 goto out;
4129 }
4130
4131 field_var = create_target_field_var(target_hist_data: hist_data, NULL, NULL, var_name: param);
4132 if (IS_ERR(ptr: field_var)) {
4133 hist_err(tr, err_type: HIST_ERR_FIELD_VAR_CREATE_FAIL,
4134 err_pos: errpos(str: param));
4135 ret = PTR_ERR(ptr: field_var);
4136 kfree(objp: param);
4137 goto out;
4138 }
4139
4140 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
4141 if (field_var->val->flags &
4142 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
4143 hist_data->n_save_var_str++;
4144 kfree(objp: param);
4145 }
4146 }
4147 out:
4148 return ret;
4149}
4150
4151static int onmatch_create(struct hist_trigger_data *hist_data,
4152 struct action_data *data)
4153{
4154 return action_create(hist_data, data);
4155}
4156
4157static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
4158{
4159 char *match_event, *match_event_system;
4160 struct action_data *data;
4161 int ret = -EINVAL;
4162
4163 data = kzalloc(size: sizeof(*data), GFP_KERNEL);
4164 if (!data)
4165 return ERR_PTR(error: -ENOMEM);
4166
4167 match_event = strsep(&str, ")");
4168 if (!match_event || !str) {
4169 hist_err(tr, err_type: HIST_ERR_NO_CLOSING_PAREN, err_pos: errpos(str: match_event));
4170 goto free;
4171 }
4172
4173 match_event_system = strsep(&match_event, ".");
4174 if (!match_event) {
4175 hist_err(tr, err_type: HIST_ERR_SUBSYS_NOT_FOUND, err_pos: errpos(str: match_event_system));
4176 goto free;
4177 }
4178
4179 if (IS_ERR(ptr: event_file(tr, system: match_event_system, event_name: match_event))) {
4180 hist_err(tr, err_type: HIST_ERR_INVALID_SUBSYS_EVENT, err_pos: errpos(str: match_event));
4181 goto free;
4182 }
4183
4184 data->match_data.event = kstrdup(s: match_event, GFP_KERNEL);
4185 if (!data->match_data.event) {
4186 ret = -ENOMEM;
4187 goto free;
4188 }
4189
4190 data->match_data.event_system = kstrdup(s: match_event_system, GFP_KERNEL);
4191 if (!data->match_data.event_system) {
4192 ret = -ENOMEM;
4193 goto free;
4194 }
4195
4196 ret = action_parse(tr, str, data, handler: HANDLER_ONMATCH);
4197 if (ret)
4198 goto free;
4199 out:
4200 return data;
4201 free:
4202 onmatch_destroy(data);
4203 data = ERR_PTR(error: ret);
4204 goto out;
4205}
4206
4207static int create_hitcount_val(struct hist_trigger_data *hist_data)
4208{
4209 hist_data->fields[HITCOUNT_IDX] =
4210 create_hist_field(hist_data, NULL, flags: HIST_FIELD_FL_HITCOUNT, NULL);
4211 if (!hist_data->fields[HITCOUNT_IDX])
4212 return -ENOMEM;
4213
4214 hist_data->n_vals++;
4215 hist_data->n_fields++;
4216
4217 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
4218 return -EINVAL;
4219
4220 return 0;
4221}
4222
4223static int __create_val_field(struct hist_trigger_data *hist_data,
4224 unsigned int val_idx,
4225 struct trace_event_file *file,
4226 char *var_name, char *field_str,
4227 unsigned long flags)
4228{
4229 struct hist_field *hist_field;
4230 int ret = 0, n_subexprs = 0;
4231
4232 hist_field = parse_expr(hist_data, file, str: field_str, flags, var_name, n_subexprs: &n_subexprs);
4233 if (IS_ERR(ptr: hist_field)) {
4234 ret = PTR_ERR(ptr: hist_field);
4235 goto out;
4236 }
4237
4238 /* values and variables should not have some modifiers */
4239 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4240 /* Variable */
4241 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT |
4242 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2))
4243 goto err;
4244 } else {
4245 /* Value */
4246 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT |
4247 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 |
4248 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET |
4249 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE))
4250 goto err;
4251 }
4252
4253 hist_data->fields[val_idx] = hist_field;
4254
4255 ++hist_data->n_vals;
4256 ++hist_data->n_fields;
4257
4258 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4259 ret = -EINVAL;
4260 out:
4261 return ret;
4262 err:
4263 hist_err(tr: file->tr, err_type: HIST_ERR_BAD_FIELD_MODIFIER, err_pos: errpos(str: field_str));
4264 return -EINVAL;
4265}
4266
4267static int create_val_field(struct hist_trigger_data *hist_data,
4268 unsigned int val_idx,
4269 struct trace_event_file *file,
4270 char *field_str)
4271{
4272 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
4273 return -EINVAL;
4274
4275 return __create_val_field(hist_data, val_idx, file, NULL, field_str, flags: 0);
4276}
4277
4278static const char no_comm[] = "(no comm)";
4279
4280static u64 hist_field_execname(struct hist_field *hist_field,
4281 struct tracing_map_elt *elt,
4282 struct trace_buffer *buffer,
4283 struct ring_buffer_event *rbe,
4284 void *event)
4285{
4286 struct hist_elt_data *elt_data;
4287
4288 if (WARN_ON_ONCE(!elt))
4289 return (u64)(unsigned long)no_comm;
4290
4291 elt_data = elt->private_data;
4292
4293 if (WARN_ON_ONCE(!elt_data->comm))
4294 return (u64)(unsigned long)no_comm;
4295
4296 return (u64)(unsigned long)(elt_data->comm);
4297}
4298
4299static u64 hist_field_stack(struct hist_field *hist_field,
4300 struct tracing_map_elt *elt,
4301 struct trace_buffer *buffer,
4302 struct ring_buffer_event *rbe,
4303 void *event)
4304{
4305 u32 str_item = *(u32 *)(event + hist_field->field->offset);
4306 int str_loc = str_item & 0xffff;
4307 char *addr = (char *)(event + str_loc);
4308
4309 return (u64)(unsigned long)addr;
4310}
4311
4312static u64 hist_fn_call(struct hist_field *hist_field,
4313 struct tracing_map_elt *elt,
4314 struct trace_buffer *buffer,
4315 struct ring_buffer_event *rbe,
4316 void *event)
4317{
4318 switch (hist_field->fn_num) {
4319 case HIST_FIELD_FN_VAR_REF:
4320 return hist_field_var_ref(hist_field, elt, buffer, rbe, event);
4321 case HIST_FIELD_FN_COUNTER:
4322 return hist_field_counter(field: hist_field, elt, buffer, rbe, event);
4323 case HIST_FIELD_FN_CONST:
4324 return hist_field_const(field: hist_field, elt, buffer, rbe, event);
4325 case HIST_FIELD_FN_LOG2:
4326 return hist_field_log2(hist_field, elt, buffer, rbe, event);
4327 case HIST_FIELD_FN_BUCKET:
4328 return hist_field_bucket(hist_field, elt, buffer, rbe, event);
4329 case HIST_FIELD_FN_TIMESTAMP:
4330 return hist_field_timestamp(hist_field, elt, buffer, rbe, event);
4331 case HIST_FIELD_FN_CPU:
4332 return hist_field_cpu(hist_field, elt, buffer, rbe, event);
4333 case HIST_FIELD_FN_STRING:
4334 return hist_field_string(hist_field, elt, buffer, rbe, event);
4335 case HIST_FIELD_FN_DYNSTRING:
4336 return hist_field_dynstring(hist_field, elt, buffer, rbe, event);
4337 case HIST_FIELD_FN_RELDYNSTRING:
4338 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event);
4339 case HIST_FIELD_FN_PSTRING:
4340 return hist_field_pstring(hist_field, elt, buffer, rbe, event);
4341 case HIST_FIELD_FN_S64:
4342 return hist_field_s64(hist_field, elt, buffer, rbe, event);
4343 case HIST_FIELD_FN_U64:
4344 return hist_field_u64(hist_field, elt, buffer, rbe, event);
4345 case HIST_FIELD_FN_S32:
4346 return hist_field_s32(hist_field, elt, buffer, rbe, event);
4347 case HIST_FIELD_FN_U32:
4348 return hist_field_u32(hist_field, elt, buffer, rbe, event);
4349 case HIST_FIELD_FN_S16:
4350 return hist_field_s16(hist_field, elt, buffer, rbe, event);
4351 case HIST_FIELD_FN_U16:
4352 return hist_field_u16(hist_field, elt, buffer, rbe, event);
4353 case HIST_FIELD_FN_S8:
4354 return hist_field_s8(hist_field, elt, buffer, rbe, event);
4355 case HIST_FIELD_FN_U8:
4356 return hist_field_u8(hist_field, elt, buffer, rbe, event);
4357 case HIST_FIELD_FN_UMINUS:
4358 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event);
4359 case HIST_FIELD_FN_MINUS:
4360 return hist_field_minus(hist_field, elt, buffer, rbe, event);
4361 case HIST_FIELD_FN_PLUS:
4362 return hist_field_plus(hist_field, elt, buffer, rbe, event);
4363 case HIST_FIELD_FN_DIV:
4364 return hist_field_div(hist_field, elt, buffer, rbe, event);
4365 case HIST_FIELD_FN_MULT:
4366 return hist_field_mult(hist_field, elt, buffer, rbe, event);
4367 case HIST_FIELD_FN_DIV_POWER2:
4368 return div_by_power_of_two(hist_field, elt, buffer, rbe, event);
4369 case HIST_FIELD_FN_DIV_NOT_POWER2:
4370 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event);
4371 case HIST_FIELD_FN_DIV_MULT_SHIFT:
4372 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event);
4373 case HIST_FIELD_FN_EXECNAME:
4374 return hist_field_execname(hist_field, elt, buffer, rbe, event);
4375 case HIST_FIELD_FN_STACK:
4376 return hist_field_stack(hist_field, elt, buffer, rbe, event);
4377 default:
4378 return 0;
4379 }
4380}
4381
4382/* Convert a var that points to common_pid.execname to a string */
4383static void update_var_execname(struct hist_field *hist_field)
4384{
4385 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR |
4386 HIST_FIELD_FL_EXECNAME;
4387 hist_field->size = MAX_FILTER_STR_VAL;
4388 hist_field->is_signed = 0;
4389
4390 kfree_const(x: hist_field->type);
4391 hist_field->type = "char[]";
4392
4393 hist_field->fn_num = HIST_FIELD_FN_EXECNAME;
4394}
4395
4396static int create_var_field(struct hist_trigger_data *hist_data,
4397 unsigned int val_idx,
4398 struct trace_event_file *file,
4399 char *var_name, char *expr_str)
4400{
4401 struct trace_array *tr = hist_data->event_file->tr;
4402 unsigned long flags = 0;
4403 int ret;
4404
4405 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4406 return -EINVAL;
4407
4408 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
4409 hist_err(tr, err_type: HIST_ERR_DUPLICATE_VAR, err_pos: errpos(str: var_name));
4410 return -EINVAL;
4411 }
4412
4413 flags |= HIST_FIELD_FL_VAR;
4414 hist_data->n_vars++;
4415 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
4416 return -EINVAL;
4417
4418 ret = __create_val_field(hist_data, val_idx, file, var_name, field_str: expr_str, flags);
4419
4420 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME)
4421 update_var_execname(hist_field: hist_data->fields[val_idx]);
4422
4423 if (!ret && hist_data->fields[val_idx]->flags &
4424 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE))
4425 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
4426
4427 return ret;
4428}
4429
4430static int create_val_fields(struct hist_trigger_data *hist_data,
4431 struct trace_event_file *file)
4432{
4433 unsigned int i, j = 1, n_hitcount = 0;
4434 char *fields_str, *field_str;
4435 int ret;
4436
4437 ret = create_hitcount_val(hist_data);
4438 if (ret)
4439 goto out;
4440
4441 fields_str = hist_data->attrs->vals_str;
4442 if (!fields_str)
4443 goto out;
4444
4445 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
4446 j < TRACING_MAP_VALS_MAX; i++) {
4447 field_str = strsep(&fields_str, ",");
4448 if (!field_str)
4449 break;
4450
4451 if (strcmp(field_str, "hitcount") == 0) {
4452 if (!n_hitcount++)
4453 continue;
4454 }
4455
4456 ret = create_val_field(hist_data, val_idx: j++, file, field_str);
4457 if (ret)
4458 goto out;
4459 }
4460
4461 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
4462 ret = -EINVAL;
4463 out:
4464 /* There is only raw hitcount but nohitcount suppresses it. */
4465 if (j == 1 && hist_data->attrs->no_hitcount) {
4466 hist_err(tr: hist_data->event_file->tr, err_type: HIST_ERR_NEED_NOHC_VAL, err_pos: 0);
4467 ret = -ENOENT;
4468 }
4469
4470 return ret;
4471}
4472
4473static int create_key_field(struct hist_trigger_data *hist_data,
4474 unsigned int key_idx,
4475 unsigned int key_offset,
4476 struct trace_event_file *file,
4477 char *field_str)
4478{
4479 struct trace_array *tr = hist_data->event_file->tr;
4480 struct hist_field *hist_field = NULL;
4481 unsigned long flags = 0;
4482 unsigned int key_size;
4483 int ret = 0, n_subexprs = 0;
4484
4485 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
4486 return -EINVAL;
4487
4488 flags |= HIST_FIELD_FL_KEY;
4489
4490 if (strcmp(field_str, "stacktrace") == 0) {
4491 flags |= HIST_FIELD_FL_STACKTRACE;
4492 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
4493 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
4494 } else {
4495 hist_field = parse_expr(hist_data, file, str: field_str, flags,
4496 NULL, n_subexprs: &n_subexprs);
4497 if (IS_ERR(ptr: hist_field)) {
4498 ret = PTR_ERR(ptr: hist_field);
4499 goto out;
4500 }
4501
4502 if (field_has_hist_vars(hist_field, level: 0)) {
4503 hist_err(tr, err_type: HIST_ERR_INVALID_REF_KEY, err_pos: errpos(str: field_str));
4504 destroy_hist_field(hist_field, level: 0);
4505 ret = -EINVAL;
4506 goto out;
4507 }
4508
4509 key_size = hist_field->size;
4510 }
4511
4512 hist_data->fields[key_idx] = hist_field;
4513
4514 key_size = ALIGN(key_size, sizeof(u64));
4515 hist_data->fields[key_idx]->size = key_size;
4516 hist_data->fields[key_idx]->offset = key_offset;
4517
4518 hist_data->key_size += key_size;
4519
4520 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
4521 ret = -EINVAL;
4522 goto out;
4523 }
4524
4525 hist_data->n_keys++;
4526 hist_data->n_fields++;
4527
4528 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
4529 return -EINVAL;
4530
4531 ret = key_size;
4532 out:
4533 return ret;
4534}
4535
4536static int create_key_fields(struct hist_trigger_data *hist_data,
4537 struct trace_event_file *file)
4538{
4539 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
4540 char *fields_str, *field_str;
4541 int ret = -EINVAL;
4542
4543 fields_str = hist_data->attrs->keys_str;
4544 if (!fields_str)
4545 goto out;
4546
4547 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4548 field_str = strsep(&fields_str, ",");
4549 if (!field_str)
4550 break;
4551 ret = create_key_field(hist_data, key_idx: i, key_offset,
4552 file, field_str);
4553 if (ret < 0)
4554 goto out;
4555 key_offset += ret;
4556 }
4557 if (fields_str) {
4558 ret = -EINVAL;
4559 goto out;
4560 }
4561 ret = 0;
4562 out:
4563 return ret;
4564}
4565
4566static int create_var_fields(struct hist_trigger_data *hist_data,
4567 struct trace_event_file *file)
4568{
4569 unsigned int i, j = hist_data->n_vals;
4570 int ret = 0;
4571
4572 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4573
4574 for (i = 0; i < n_vars; i++) {
4575 char *var_name = hist_data->attrs->var_defs.name[i];
4576 char *expr = hist_data->attrs->var_defs.expr[i];
4577
4578 ret = create_var_field(hist_data, val_idx: j++, file, var_name, expr_str: expr);
4579 if (ret)
4580 goto out;
4581 }
4582 out:
4583 return ret;
4584}
4585
4586static void free_var_defs(struct hist_trigger_data *hist_data)
4587{
4588 unsigned int i;
4589
4590 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4591 kfree(objp: hist_data->attrs->var_defs.name[i]);
4592 kfree(objp: hist_data->attrs->var_defs.expr[i]);
4593 }
4594
4595 hist_data->attrs->var_defs.n_vars = 0;
4596}
4597
4598static int parse_var_defs(struct hist_trigger_data *hist_data)
4599{
4600 struct trace_array *tr = hist_data->event_file->tr;
4601 char *s, *str, *var_name, *field_str;
4602 unsigned int i, j, n_vars = 0;
4603 int ret = 0;
4604
4605 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4606 str = hist_data->attrs->assignment_str[i];
4607 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4608 field_str = strsep(&str, ",");
4609 if (!field_str)
4610 break;
4611
4612 var_name = strsep(&field_str, "=");
4613 if (!var_name || !field_str) {
4614 hist_err(tr, err_type: HIST_ERR_MALFORMED_ASSIGNMENT,
4615 err_pos: errpos(str: var_name));
4616 ret = -EINVAL;
4617 goto free;
4618 }
4619
4620 if (n_vars == TRACING_MAP_VARS_MAX) {
4621 hist_err(tr, err_type: HIST_ERR_TOO_MANY_VARS, err_pos: errpos(str: var_name));
4622 ret = -EINVAL;
4623 goto free;
4624 }
4625
4626 s = kstrdup(s: var_name, GFP_KERNEL);
4627 if (!s) {
4628 ret = -ENOMEM;
4629 goto free;
4630 }
4631 hist_data->attrs->var_defs.name[n_vars] = s;
4632
4633 s = kstrdup(s: field_str, GFP_KERNEL);
4634 if (!s) {
4635 kfree(objp: hist_data->attrs->var_defs.name[n_vars]);
4636 hist_data->attrs->var_defs.name[n_vars] = NULL;
4637 ret = -ENOMEM;
4638 goto free;
4639 }
4640 hist_data->attrs->var_defs.expr[n_vars++] = s;
4641
4642 hist_data->attrs->var_defs.n_vars = n_vars;
4643 }
4644 }
4645
4646 return ret;
4647 free:
4648 free_var_defs(hist_data);
4649
4650 return ret;
4651}
4652
4653static int create_hist_fields(struct hist_trigger_data *hist_data,
4654 struct trace_event_file *file)
4655{
4656 int ret;
4657
4658 ret = parse_var_defs(hist_data);
4659 if (ret)
4660 return ret;
4661
4662 ret = create_val_fields(hist_data, file);
4663 if (ret)
4664 goto out;
4665
4666 ret = create_var_fields(hist_data, file);
4667 if (ret)
4668 goto out;
4669
4670 ret = create_key_fields(hist_data, file);
4671
4672 out:
4673 free_var_defs(hist_data);
4674
4675 return ret;
4676}
4677
4678static int is_descending(struct trace_array *tr, const char *str)
4679{
4680 if (!str)
4681 return 0;
4682
4683 if (strcmp(str, "descending") == 0)
4684 return 1;
4685
4686 if (strcmp(str, "ascending") == 0)
4687 return 0;
4688
4689 hist_err(tr, err_type: HIST_ERR_INVALID_SORT_MODIFIER, err_pos: errpos(str: (char *)str));
4690
4691 return -EINVAL;
4692}
4693
4694static int create_sort_keys(struct hist_trigger_data *hist_data)
4695{
4696 struct trace_array *tr = hist_data->event_file->tr;
4697 char *fields_str = hist_data->attrs->sort_key_str;
4698 struct tracing_map_sort_key *sort_key;
4699 int descending, ret = 0;
4700 unsigned int i, j, k;
4701
4702 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4703
4704 if (!fields_str)
4705 goto out;
4706
4707 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4708 struct hist_field *hist_field;
4709 char *field_str, *field_name;
4710 const char *test_name;
4711
4712 sort_key = &hist_data->sort_keys[i];
4713
4714 field_str = strsep(&fields_str, ",");
4715 if (!field_str)
4716 break;
4717
4718 if (!*field_str) {
4719 ret = -EINVAL;
4720 hist_err(tr, err_type: HIST_ERR_EMPTY_SORT_FIELD, err_pos: errpos(str: "sort="));
4721 break;
4722 }
4723
4724 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4725 hist_err(tr, err_type: HIST_ERR_TOO_MANY_SORT_FIELDS, err_pos: errpos(str: "sort="));
4726 ret = -EINVAL;
4727 break;
4728 }
4729
4730 field_name = strsep(&field_str, ".");
4731 if (!field_name || !*field_name) {
4732 ret = -EINVAL;
4733 hist_err(tr, err_type: HIST_ERR_EMPTY_SORT_FIELD, err_pos: errpos(str: "sort="));
4734 break;
4735 }
4736
4737 if (strcmp(field_name, "hitcount") == 0) {
4738 descending = is_descending(tr, str: field_str);
4739 if (descending < 0) {
4740 ret = descending;
4741 break;
4742 }
4743 sort_key->descending = descending;
4744 continue;
4745 }
4746
4747 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4748 unsigned int idx;
4749
4750 hist_field = hist_data->fields[j];
4751 if (hist_field->flags & HIST_FIELD_FL_VAR)
4752 continue;
4753
4754 idx = k++;
4755
4756 test_name = hist_field_name(field: hist_field, level: 0);
4757
4758 if (strcmp(field_name, test_name) == 0) {
4759 sort_key->field_idx = idx;
4760 descending = is_descending(tr, str: field_str);
4761 if (descending < 0) {
4762 ret = descending;
4763 goto out;
4764 }
4765 sort_key->descending = descending;
4766 break;
4767 }
4768 }
4769 if (j == hist_data->n_fields) {
4770 ret = -EINVAL;
4771 hist_err(tr, err_type: HIST_ERR_INVALID_SORT_FIELD, err_pos: errpos(str: field_name));
4772 break;
4773 }
4774 }
4775
4776 hist_data->n_sort_keys = i;
4777 out:
4778 return ret;
4779}
4780
4781static void destroy_actions(struct hist_trigger_data *hist_data)
4782{
4783 unsigned int i;
4784
4785 for (i = 0; i < hist_data->n_actions; i++) {
4786 struct action_data *data = hist_data->actions[i];
4787
4788 if (data->handler == HANDLER_ONMATCH)
4789 onmatch_destroy(data);
4790 else if (data->handler == HANDLER_ONMAX ||
4791 data->handler == HANDLER_ONCHANGE)
4792 track_data_destroy(hist_data, data);
4793 else
4794 kfree(objp: data);
4795 }
4796}
4797
4798static int parse_actions(struct hist_trigger_data *hist_data)
4799{
4800 struct trace_array *tr = hist_data->event_file->tr;
4801 struct action_data *data;
4802 unsigned int i;
4803 int ret = 0;
4804 char *str;
4805 int len;
4806
4807 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4808 str = hist_data->attrs->action_str[i];
4809
4810 if ((len = str_has_prefix(str, prefix: "onmatch("))) {
4811 char *action_str = str + len;
4812
4813 data = onmatch_parse(tr, str: action_str);
4814 if (IS_ERR(ptr: data)) {
4815 ret = PTR_ERR(ptr: data);
4816 break;
4817 }
4818 } else if ((len = str_has_prefix(str, prefix: "onmax("))) {
4819 char *action_str = str + len;
4820
4821 data = track_data_parse(hist_data, str: action_str,
4822 handler: HANDLER_ONMAX);
4823 if (IS_ERR(ptr: data)) {
4824 ret = PTR_ERR(ptr: data);
4825 break;
4826 }
4827 } else if ((len = str_has_prefix(str, prefix: "onchange("))) {
4828 char *action_str = str + len;
4829
4830 data = track_data_parse(hist_data, str: action_str,
4831 handler: HANDLER_ONCHANGE);
4832 if (IS_ERR(ptr: data)) {
4833 ret = PTR_ERR(ptr: data);
4834 break;
4835 }
4836 } else {
4837 ret = -EINVAL;
4838 break;
4839 }
4840
4841 hist_data->actions[hist_data->n_actions++] = data;
4842 }
4843
4844 return ret;
4845}
4846
4847static int create_actions(struct hist_trigger_data *hist_data)
4848{
4849 struct action_data *data;
4850 unsigned int i;
4851 int ret = 0;
4852
4853 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4854 data = hist_data->actions[i];
4855
4856 if (data->handler == HANDLER_ONMATCH) {
4857 ret = onmatch_create(hist_data, data);
4858 if (ret)
4859 break;
4860 } else if (data->handler == HANDLER_ONMAX ||
4861 data->handler == HANDLER_ONCHANGE) {
4862 ret = track_data_create(hist_data, data);
4863 if (ret)
4864 break;
4865 } else {
4866 ret = -EINVAL;
4867 break;
4868 }
4869 }
4870
4871 return ret;
4872}
4873
4874static void print_actions(struct seq_file *m,
4875 struct hist_trigger_data *hist_data,
4876 struct tracing_map_elt *elt)
4877{
4878 unsigned int i;
4879
4880 for (i = 0; i < hist_data->n_actions; i++) {
4881 struct action_data *data = hist_data->actions[i];
4882
4883 if (data->action == ACTION_SNAPSHOT)
4884 continue;
4885
4886 if (data->handler == HANDLER_ONMAX ||
4887 data->handler == HANDLER_ONCHANGE)
4888 track_data_print(m, hist_data, elt, data);
4889 }
4890}
4891
4892static void print_action_spec(struct seq_file *m,
4893 struct hist_trigger_data *hist_data,
4894 struct action_data *data)
4895{
4896 unsigned int i;
4897
4898 if (data->action == ACTION_SAVE) {
4899 for (i = 0; i < hist_data->n_save_vars; i++) {
4900 seq_printf(m, fmt: "%s", hist_data->save_vars[i]->var->var.name);
4901 if (i < hist_data->n_save_vars - 1)
4902 seq_puts(m, s: ",");
4903 }
4904 } else if (data->action == ACTION_TRACE) {
4905 if (data->use_trace_keyword)
4906 seq_printf(m, fmt: "%s", data->synth_event_name);
4907 for (i = 0; i < data->n_params; i++) {
4908 if (i || data->use_trace_keyword)
4909 seq_puts(m, s: ",");
4910 seq_printf(m, fmt: "%s", data->params[i]);
4911 }
4912 }
4913}
4914
4915static void print_track_data_spec(struct seq_file *m,
4916 struct hist_trigger_data *hist_data,
4917 struct action_data *data)
4918{
4919 if (data->handler == HANDLER_ONMAX)
4920 seq_puts(m, s: ":onmax(");
4921 else if (data->handler == HANDLER_ONCHANGE)
4922 seq_puts(m, s: ":onchange(");
4923 seq_printf(m, fmt: "%s", data->track_data.var_str);
4924 seq_printf(m, fmt: ").%s(", data->action_name);
4925
4926 print_action_spec(m, hist_data, data);
4927
4928 seq_puts(m, s: ")");
4929}
4930
4931static void print_onmatch_spec(struct seq_file *m,
4932 struct hist_trigger_data *hist_data,
4933 struct action_data *data)
4934{
4935 seq_printf(m, fmt: ":onmatch(%s.%s).", data->match_data.event_system,
4936 data->match_data.event);
4937
4938 seq_printf(m, fmt: "%s(", data->action_name);
4939
4940 print_action_spec(m, hist_data, data);
4941
4942 seq_puts(m, s: ")");
4943}
4944
4945static bool actions_match(struct hist_trigger_data *hist_data,
4946 struct hist_trigger_data *hist_data_test)
4947{
4948 unsigned int i, j;
4949
4950 if (hist_data->n_actions != hist_data_test->n_actions)
4951 return false;
4952
4953 for (i = 0; i < hist_data->n_actions; i++) {
4954 struct action_data *data = hist_data->actions[i];
4955 struct action_data *data_test = hist_data_test->actions[i];
4956 char *action_name, *action_name_test;
4957
4958 if (data->handler != data_test->handler)
4959 return false;
4960 if (data->action != data_test->action)
4961 return false;
4962
4963 if (data->n_params != data_test->n_params)
4964 return false;
4965
4966 for (j = 0; j < data->n_params; j++) {
4967 if (strcmp(data->params[j], data_test->params[j]) != 0)
4968 return false;
4969 }
4970
4971 if (data->use_trace_keyword)
4972 action_name = data->synth_event_name;
4973 else
4974 action_name = data->action_name;
4975
4976 if (data_test->use_trace_keyword)
4977 action_name_test = data_test->synth_event_name;
4978 else
4979 action_name_test = data_test->action_name;
4980
4981 if (strcmp(action_name, action_name_test) != 0)
4982 return false;
4983
4984 if (data->handler == HANDLER_ONMATCH) {
4985 if (strcmp(data->match_data.event_system,
4986 data_test->match_data.event_system) != 0)
4987 return false;
4988 if (strcmp(data->match_data.event,
4989 data_test->match_data.event) != 0)
4990 return false;
4991 } else if (data->handler == HANDLER_ONMAX ||
4992 data->handler == HANDLER_ONCHANGE) {
4993 if (strcmp(data->track_data.var_str,
4994 data_test->track_data.var_str) != 0)
4995 return false;
4996 }
4997 }
4998
4999 return true;
5000}
5001
5002
5003static void print_actions_spec(struct seq_file *m,
5004 struct hist_trigger_data *hist_data)
5005{
5006 unsigned int i;
5007
5008 for (i = 0; i < hist_data->n_actions; i++) {
5009 struct action_data *data = hist_data->actions[i];
5010
5011 if (data->handler == HANDLER_ONMATCH)
5012 print_onmatch_spec(m, hist_data, data);
5013 else if (data->handler == HANDLER_ONMAX ||
5014 data->handler == HANDLER_ONCHANGE)
5015 print_track_data_spec(m, hist_data, data);
5016 }
5017}
5018
5019static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
5020{
5021 unsigned int i;
5022
5023 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5024 kfree(objp: hist_data->field_var_hists[i]->cmd);
5025 kfree(objp: hist_data->field_var_hists[i]);
5026 }
5027}
5028
5029static void destroy_hist_data(struct hist_trigger_data *hist_data)
5030{
5031 if (!hist_data)
5032 return;
5033
5034 destroy_hist_trigger_attrs(attrs: hist_data->attrs);
5035 destroy_hist_fields(hist_data);
5036 tracing_map_destroy(map: hist_data->map);
5037
5038 destroy_actions(hist_data);
5039 destroy_field_vars(hist_data);
5040 destroy_field_var_hists(hist_data);
5041
5042 kfree(objp: hist_data);
5043}
5044
5045static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
5046{
5047 struct tracing_map *map = hist_data->map;
5048 struct ftrace_event_field *field;
5049 struct hist_field *hist_field;
5050 int i, idx = 0;
5051
5052 for_each_hist_field(i, hist_data) {
5053 hist_field = hist_data->fields[i];
5054 if (hist_field->flags & HIST_FIELD_FL_KEY) {
5055 tracing_map_cmp_fn_t cmp_fn;
5056
5057 field = hist_field->field;
5058
5059 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
5060 cmp_fn = tracing_map_cmp_none;
5061 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU)
5062 cmp_fn = tracing_map_cmp_num(field_size: hist_field->size,
5063 field_is_signed: hist_field->is_signed);
5064 else if (is_string_field(field))
5065 cmp_fn = tracing_map_cmp_string;
5066 else
5067 cmp_fn = tracing_map_cmp_num(field_size: field->size,
5068 field_is_signed: field->is_signed);
5069 idx = tracing_map_add_key_field(map,
5070 offset: hist_field->offset,
5071 cmp_fn);
5072 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
5073 idx = tracing_map_add_sum_field(map);
5074
5075 if (idx < 0)
5076 return idx;
5077
5078 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5079 idx = tracing_map_add_var(map);
5080 if (idx < 0)
5081 return idx;
5082 hist_field->var.idx = idx;
5083 hist_field->var.hist_data = hist_data;
5084 }
5085 }
5086
5087 return 0;
5088}
5089
5090static struct hist_trigger_data *
5091create_hist_data(unsigned int map_bits,
5092 struct hist_trigger_attrs *attrs,
5093 struct trace_event_file *file,
5094 bool remove)
5095{
5096 const struct tracing_map_ops *map_ops = NULL;
5097 struct hist_trigger_data *hist_data;
5098 int ret = 0;
5099
5100 hist_data = kzalloc(size: sizeof(*hist_data), GFP_KERNEL);
5101 if (!hist_data)
5102 return ERR_PTR(error: -ENOMEM);
5103
5104 hist_data->attrs = attrs;
5105 hist_data->remove = remove;
5106 hist_data->event_file = file;
5107
5108 ret = parse_actions(hist_data);
5109 if (ret)
5110 goto free;
5111
5112 ret = create_hist_fields(hist_data, file);
5113 if (ret)
5114 goto free;
5115
5116 ret = create_sort_keys(hist_data);
5117 if (ret)
5118 goto free;
5119
5120 map_ops = &hist_trigger_elt_data_ops;
5121
5122 hist_data->map = tracing_map_create(map_bits, key_size: hist_data->key_size,
5123 ops: map_ops, private_data: hist_data);
5124 if (IS_ERR(ptr: hist_data->map)) {
5125 ret = PTR_ERR(ptr: hist_data->map);
5126 hist_data->map = NULL;
5127 goto free;
5128 }
5129
5130 ret = create_tracing_map_fields(hist_data);
5131 if (ret)
5132 goto free;
5133 out:
5134 return hist_data;
5135 free:
5136 hist_data->attrs = NULL;
5137
5138 destroy_hist_data(hist_data);
5139
5140 hist_data = ERR_PTR(error: ret);
5141
5142 goto out;
5143}
5144
5145static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
5146 struct tracing_map_elt *elt,
5147 struct trace_buffer *buffer, void *rec,
5148 struct ring_buffer_event *rbe,
5149 u64 *var_ref_vals)
5150{
5151 struct hist_elt_data *elt_data;
5152 struct hist_field *hist_field;
5153 unsigned int i, var_idx;
5154 u64 hist_val;
5155
5156 elt_data = elt->private_data;
5157 elt_data->var_ref_vals = var_ref_vals;
5158
5159 for_each_hist_val_field(i, hist_data) {
5160 hist_field = hist_data->fields[i];
5161 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, event: rec);
5162 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5163 var_idx = hist_field->var.idx;
5164
5165 if (hist_field->flags &
5166 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) {
5167 unsigned int str_start, var_str_idx, idx;
5168 char *str, *val_str;
5169 unsigned int size;
5170
5171 str_start = hist_data->n_field_var_str +
5172 hist_data->n_save_var_str;
5173 var_str_idx = hist_field->var_str_idx;
5174 idx = str_start + var_str_idx;
5175
5176 str = elt_data->field_var_str[idx];
5177 val_str = (char *)(uintptr_t)hist_val;
5178
5179 if (hist_field->flags & HIST_FIELD_FL_STRING) {
5180 size = min(hist_field->size, STR_VAR_LEN_MAX);
5181 strscpy(p: str, q: val_str, size);
5182 } else {
5183 char *stack_start = str + sizeof(unsigned long);
5184 int e;
5185
5186 e = stack_trace_save(store: (void *)stack_start,
5187 HIST_STACKTRACE_DEPTH,
5188 HIST_STACKTRACE_SKIP);
5189 if (e < HIST_STACKTRACE_DEPTH - 1)
5190 ((unsigned long *)stack_start)[e] = 0;
5191 *((unsigned long *)str) = e;
5192 }
5193 hist_val = (u64)(uintptr_t)str;
5194 }
5195 tracing_map_set_var(elt, i: var_idx, n: hist_val);
5196 continue;
5197 }
5198 tracing_map_update_sum(elt, i, n: hist_val);
5199 }
5200
5201 for_each_hist_key_field(i, hist_data) {
5202 hist_field = hist_data->fields[i];
5203 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5204 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, event: rec);
5205 var_idx = hist_field->var.idx;
5206 tracing_map_set_var(elt, i: var_idx, n: hist_val);
5207 }
5208 }
5209
5210 update_field_vars(hist_data, elt, buffer, rbe, rec);
5211}
5212
5213static inline void add_to_key(char *compound_key, void *key,
5214 struct hist_field *key_field, void *rec)
5215{
5216 size_t size = key_field->size;
5217
5218 if (key_field->flags & HIST_FIELD_FL_STRING) {
5219 struct ftrace_event_field *field;
5220
5221 field = key_field->field;
5222 if (field->filter_type == FILTER_DYN_STRING ||
5223 field->filter_type == FILTER_RDYN_STRING)
5224 size = *(u32 *)(rec + field->offset) >> 16;
5225 else if (field->filter_type == FILTER_STATIC_STRING)
5226 size = field->size;
5227
5228 /* ensure NULL-termination */
5229 if (size > key_field->size - 1)
5230 size = key_field->size - 1;
5231
5232 strncpy(p: compound_key + key_field->offset, q: (char *)key, size);
5233 } else
5234 memcpy(compound_key + key_field->offset, key, size);
5235}
5236
5237static void
5238hist_trigger_actions(struct hist_trigger_data *hist_data,
5239 struct tracing_map_elt *elt,
5240 struct trace_buffer *buffer, void *rec,
5241 struct ring_buffer_event *rbe, void *key,
5242 u64 *var_ref_vals)
5243{
5244 struct action_data *data;
5245 unsigned int i;
5246
5247 for (i = 0; i < hist_data->n_actions; i++) {
5248 data = hist_data->actions[i];
5249 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals);
5250 }
5251}
5252
5253static void event_hist_trigger(struct event_trigger_data *data,
5254 struct trace_buffer *buffer, void *rec,
5255 struct ring_buffer_event *rbe)
5256{
5257 struct hist_trigger_data *hist_data = data->private_data;
5258 bool use_compound_key = (hist_data->n_keys > 1);
5259 unsigned long entries[HIST_STACKTRACE_DEPTH];
5260 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
5261 char compound_key[HIST_KEY_SIZE_MAX];
5262 struct tracing_map_elt *elt = NULL;
5263 struct hist_field *key_field;
5264 u64 field_contents;
5265 void *key = NULL;
5266 unsigned int i;
5267
5268 if (unlikely(!rbe))
5269 return;
5270
5271 memset(compound_key, 0, hist_data->key_size);
5272
5273 for_each_hist_key_field(i, hist_data) {
5274 key_field = hist_data->fields[i];
5275
5276 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5277 memset(entries, 0, HIST_STACKTRACE_SIZE);
5278 if (key_field->field) {
5279 unsigned long *stack, n_entries;
5280
5281 field_contents = hist_fn_call(hist_field: key_field, elt, buffer, rbe, event: rec);
5282 stack = (unsigned long *)(long)field_contents;
5283 n_entries = *stack;
5284 memcpy(entries, ++stack, n_entries * sizeof(unsigned long));
5285 } else {
5286 stack_trace_save(store: entries, HIST_STACKTRACE_DEPTH,
5287 HIST_STACKTRACE_SKIP);
5288 }
5289 key = entries;
5290 } else {
5291 field_contents = hist_fn_call(hist_field: key_field, elt, buffer, rbe, event: rec);
5292 if (key_field->flags & HIST_FIELD_FL_STRING) {
5293 key = (void *)(unsigned long)field_contents;
5294 use_compound_key = true;
5295 } else
5296 key = (void *)&field_contents;
5297 }
5298
5299 if (use_compound_key)
5300 add_to_key(compound_key, key, key_field, rec);
5301 }
5302
5303 if (use_compound_key)
5304 key = compound_key;
5305
5306 if (hist_data->n_var_refs &&
5307 !resolve_var_refs(hist_data, key, var_ref_vals, self: false))
5308 return;
5309
5310 elt = tracing_map_insert(map: hist_data->map, key);
5311 if (!elt)
5312 return;
5313
5314 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals);
5315
5316 if (resolve_var_refs(hist_data, key, var_ref_vals, self: true))
5317 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals);
5318}
5319
5320static void hist_trigger_stacktrace_print(struct seq_file *m,
5321 unsigned long *stacktrace_entries,
5322 unsigned int max_entries)
5323{
5324 unsigned int spaces = 8;
5325 unsigned int i;
5326
5327 for (i = 0; i < max_entries; i++) {
5328 if (!stacktrace_entries[i])
5329 return;
5330
5331 seq_printf(m, fmt: "%*c", 1 + spaces, ' ');
5332 seq_printf(m, fmt: "%pS\n", (void*)stacktrace_entries[i]);
5333 }
5334}
5335
5336static void hist_trigger_print_key(struct seq_file *m,
5337 struct hist_trigger_data *hist_data,
5338 void *key,
5339 struct tracing_map_elt *elt)
5340{
5341 struct hist_field *key_field;
5342 bool multiline = false;
5343 const char *field_name;
5344 unsigned int i;
5345 u64 uval;
5346
5347 seq_puts(m, s: "{ ");
5348
5349 for_each_hist_key_field(i, hist_data) {
5350 key_field = hist_data->fields[i];
5351
5352 if (i > hist_data->n_vals)
5353 seq_puts(m, s: ", ");
5354
5355 field_name = hist_field_name(field: key_field, level: 0);
5356
5357 if (key_field->flags & HIST_FIELD_FL_HEX) {
5358 uval = *(u64 *)(key + key_field->offset);
5359 seq_printf(m, fmt: "%s: %llx", field_name, uval);
5360 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
5361 uval = *(u64 *)(key + key_field->offset);
5362 seq_printf(m, fmt: "%s: [%llx] %-45ps", field_name,
5363 uval, (void *)(uintptr_t)uval);
5364 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
5365 uval = *(u64 *)(key + key_field->offset);
5366 seq_printf(m, fmt: "%s: [%llx] %-55pS", field_name,
5367 uval, (void *)(uintptr_t)uval);
5368 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
5369 struct hist_elt_data *elt_data = elt->private_data;
5370 char *comm;
5371
5372 if (WARN_ON_ONCE(!elt_data))
5373 return;
5374
5375 comm = elt_data->comm;
5376
5377 uval = *(u64 *)(key + key_field->offset);
5378 seq_printf(m, fmt: "%s: %-16s[%10llu]", field_name,
5379 comm, uval);
5380 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
5381 const char *syscall_name;
5382
5383 uval = *(u64 *)(key + key_field->offset);
5384 syscall_name = get_syscall_name(syscall: uval);
5385 if (!syscall_name)
5386 syscall_name = "unknown_syscall";
5387
5388 seq_printf(m, fmt: "%s: %-30s[%3llu]", field_name,
5389 syscall_name, uval);
5390 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5391 if (key_field->field)
5392 seq_printf(m, fmt: "%s.stacktrace", key_field->field->name);
5393 else
5394 seq_puts(m, s: "common_stacktrace:\n");
5395 hist_trigger_stacktrace_print(m,
5396 stacktrace_entries: key + key_field->offset,
5397 HIST_STACKTRACE_DEPTH);
5398 multiline = true;
5399 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
5400 seq_printf(m, fmt: "%s: ~ 2^%-2llu", field_name,
5401 *(u64 *)(key + key_field->offset));
5402 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) {
5403 unsigned long buckets = key_field->buckets;
5404 uval = *(u64 *)(key + key_field->offset);
5405 seq_printf(m, fmt: "%s: ~ %llu-%llu", field_name,
5406 uval, uval + buckets -1);
5407 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
5408 seq_printf(m, fmt: "%s: %-50s", field_name,
5409 (char *)(key + key_field->offset));
5410 } else {
5411 uval = *(u64 *)(key + key_field->offset);
5412 seq_printf(m, fmt: "%s: %10llu", field_name, uval);
5413 }
5414 }
5415
5416 if (!multiline)
5417 seq_puts(m, s: " ");
5418
5419 seq_puts(m, s: "}");
5420}
5421
5422/* Get the 100 times of the percentage of @val in @total */
5423static inline unsigned int __get_percentage(u64 val, u64 total)
5424{
5425 if (!total)
5426 goto div0;
5427
5428 if (val < (U64_MAX / 10000))
5429 return (unsigned int)div64_ul(val * 10000, total);
5430
5431 total = div64_u64(dividend: total, divisor: 10000);
5432 if (!total)
5433 goto div0;
5434
5435 return (unsigned int)div64_ul(val, total);
5436div0:
5437 return val ? UINT_MAX : 0;
5438}
5439
5440#define BAR_CHAR '#'
5441
5442static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max)
5443{
5444 unsigned int len = __get_percentage(val, total: max);
5445 int i;
5446
5447 if (len == UINT_MAX) {
5448 snprintf(buf, size, fmt: "[ERROR]");
5449 return buf;
5450 }
5451
5452 len = len * size / 10000;
5453 for (i = 0; i < len && i < size; i++)
5454 buf[i] = BAR_CHAR;
5455 while (i < size)
5456 buf[i++] = ' ';
5457 buf[size] = '\0';
5458
5459 return buf;
5460}
5461
5462struct hist_val_stat {
5463 u64 max;
5464 u64 total;
5465};
5466
5467static void hist_trigger_print_val(struct seq_file *m, unsigned int idx,
5468 const char *field_name, unsigned long flags,
5469 struct hist_val_stat *stats,
5470 struct tracing_map_elt *elt)
5471{
5472 u64 val = tracing_map_read_sum(elt, i: idx);
5473 unsigned int pc;
5474 char bar[21];
5475
5476 if (flags & HIST_FIELD_FL_PERCENT) {
5477 pc = __get_percentage(val, total: stats[idx].total);
5478 if (pc == UINT_MAX)
5479 seq_printf(m, fmt: " %s (%%):[ERROR]", field_name);
5480 else
5481 seq_printf(m, fmt: " %s (%%): %3u.%02u", field_name,
5482 pc / 100, pc % 100);
5483 } else if (flags & HIST_FIELD_FL_GRAPH) {
5484 seq_printf(m, fmt: " %s: %20s", field_name,
5485 __fill_bar_str(buf: bar, size: 20, val, max: stats[idx].max));
5486 } else if (flags & HIST_FIELD_FL_HEX) {
5487 seq_printf(m, fmt: " %s: %10llx", field_name, val);
5488 } else {
5489 seq_printf(m, fmt: " %s: %10llu", field_name, val);
5490 }
5491}
5492
5493static void hist_trigger_entry_print(struct seq_file *m,
5494 struct hist_trigger_data *hist_data,
5495 struct hist_val_stat *stats,
5496 void *key,
5497 struct tracing_map_elt *elt)
5498{
5499 const char *field_name;
5500 unsigned int i = HITCOUNT_IDX;
5501 unsigned long flags;
5502
5503 hist_trigger_print_key(m, hist_data, key, elt);
5504
5505 /* At first, show the raw hitcount if !nohitcount */
5506 if (!hist_data->attrs->no_hitcount)
5507 hist_trigger_print_val(m, idx: i, field_name: "hitcount", flags: 0, stats, elt);
5508
5509 for (i = 1; i < hist_data->n_vals; i++) {
5510 field_name = hist_field_name(field: hist_data->fields[i], level: 0);
5511 flags = hist_data->fields[i]->flags;
5512 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR)
5513 continue;
5514
5515 seq_puts(m, s: " ");
5516 hist_trigger_print_val(m, idx: i, field_name, flags, stats, elt);
5517 }
5518
5519 print_actions(m, hist_data, elt);
5520
5521 seq_puts(m, s: "\n");
5522}
5523
5524static int print_entries(struct seq_file *m,
5525 struct hist_trigger_data *hist_data)
5526{
5527 struct tracing_map_sort_entry **sort_entries = NULL;
5528 struct tracing_map *map = hist_data->map;
5529 int i, j, n_entries;
5530 struct hist_val_stat *stats = NULL;
5531 u64 val;
5532
5533 n_entries = tracing_map_sort_entries(map, sort_keys: hist_data->sort_keys,
5534 n_sort_keys: hist_data->n_sort_keys,
5535 sort_entries: &sort_entries);
5536 if (n_entries < 0)
5537 return n_entries;
5538
5539 /* Calculate the max and the total for each field if needed. */
5540 for (j = 0; j < hist_data->n_vals; j++) {
5541 if (!(hist_data->fields[j]->flags &
5542 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH)))
5543 continue;
5544 if (!stats) {
5545 stats = kcalloc(n: hist_data->n_vals, size: sizeof(*stats),
5546 GFP_KERNEL);
5547 if (!stats) {
5548 n_entries = -ENOMEM;
5549 goto out;
5550 }
5551 }
5552 for (i = 0; i < n_entries; i++) {
5553 val = tracing_map_read_sum(elt: sort_entries[i]->elt, i: j);
5554 stats[j].total += val;
5555 if (stats[j].max < val)
5556 stats[j].max = val;
5557 }
5558 }
5559
5560 for (i = 0; i < n_entries; i++)
5561 hist_trigger_entry_print(m, hist_data, stats,
5562 key: sort_entries[i]->key,
5563 elt: sort_entries[i]->elt);
5564
5565 kfree(objp: stats);
5566out:
5567 tracing_map_destroy_sort_entries(entries: sort_entries, n_entries);
5568
5569 return n_entries;
5570}
5571
5572static void hist_trigger_show(struct seq_file *m,
5573 struct event_trigger_data *data, int n)
5574{
5575 struct hist_trigger_data *hist_data;
5576 int n_entries;
5577
5578 if (n > 0)
5579 seq_puts(m, s: "\n\n");
5580
5581 seq_puts(m, s: "# event histogram\n#\n# trigger info: ");
5582 data->ops->print(m, data);
5583 seq_puts(m, s: "#\n\n");
5584
5585 hist_data = data->private_data;
5586 n_entries = print_entries(m, hist_data);
5587 if (n_entries < 0)
5588 n_entries = 0;
5589
5590 track_data_snapshot_print(m, hist_data);
5591
5592 seq_printf(m, fmt: "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
5593 (u64)atomic64_read(v: &hist_data->map->hits),
5594 n_entries, (u64)atomic64_read(v: &hist_data->map->drops));
5595}
5596
5597static int hist_show(struct seq_file *m, void *v)
5598{
5599 struct event_trigger_data *data;
5600 struct trace_event_file *event_file;
5601 int n = 0, ret = 0;
5602
5603 mutex_lock(&event_mutex);
5604
5605 event_file = event_file_data(filp: m->private);
5606 if (unlikely(!event_file)) {
5607 ret = -ENODEV;
5608 goto out_unlock;
5609 }
5610
5611 list_for_each_entry(data, &event_file->triggers, list) {
5612 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5613 hist_trigger_show(m, data, n: n++);
5614 }
5615
5616 out_unlock:
5617 mutex_unlock(lock: &event_mutex);
5618
5619 return ret;
5620}
5621
5622static int event_hist_open(struct inode *inode, struct file *file)
5623{
5624 int ret;
5625
5626 ret = security_locked_down(what: LOCKDOWN_TRACEFS);
5627 if (ret)
5628 return ret;
5629
5630 return single_open(file, hist_show, file);
5631}
5632
5633const struct file_operations event_hist_fops = {
5634 .open = event_hist_open,
5635 .read = seq_read,
5636 .llseek = seq_lseek,
5637 .release = single_release,
5638};
5639
5640#ifdef CONFIG_HIST_TRIGGERS_DEBUG
5641static void hist_field_debug_show_flags(struct seq_file *m,
5642 unsigned long flags)
5643{
5644 seq_puts(m, s: " flags:\n");
5645
5646 if (flags & HIST_FIELD_FL_KEY)
5647 seq_puts(m, s: " HIST_FIELD_FL_KEY\n");
5648 else if (flags & HIST_FIELD_FL_HITCOUNT)
5649 seq_puts(m, s: " VAL: HIST_FIELD_FL_HITCOUNT\n");
5650 else if (flags & HIST_FIELD_FL_VAR)
5651 seq_puts(m, s: " HIST_FIELD_FL_VAR\n");
5652 else if (flags & HIST_FIELD_FL_VAR_REF)
5653 seq_puts(m, s: " HIST_FIELD_FL_VAR_REF\n");
5654 else
5655 seq_puts(m, s: " VAL: normal u64 value\n");
5656
5657 if (flags & HIST_FIELD_FL_ALIAS)
5658 seq_puts(m, s: " HIST_FIELD_FL_ALIAS\n");
5659 else if (flags & HIST_FIELD_FL_CONST)
5660 seq_puts(m, s: " HIST_FIELD_FL_CONST\n");
5661}
5662
5663static int hist_field_debug_show(struct seq_file *m,
5664 struct hist_field *field, unsigned long flags)
5665{
5666 if ((field->flags & flags) != flags) {
5667 seq_printf(m, fmt: "ERROR: bad flags - %lx\n", flags);
5668 return -EINVAL;
5669 }
5670
5671 hist_field_debug_show_flags(m, flags: field->flags);
5672 if (field->field)
5673 seq_printf(m, fmt: " ftrace_event_field name: %s\n",
5674 field->field->name);
5675
5676 if (field->flags & HIST_FIELD_FL_VAR) {
5677 seq_printf(m, fmt: " var.name: %s\n", field->var.name);
5678 seq_printf(m, fmt: " var.idx (into tracing_map_elt.vars[]): %u\n",
5679 field->var.idx);
5680 }
5681
5682 if (field->flags & HIST_FIELD_FL_CONST)
5683 seq_printf(m, fmt: " constant: %llu\n", field->constant);
5684
5685 if (field->flags & HIST_FIELD_FL_ALIAS)
5686 seq_printf(m, fmt: " var_ref_idx (into hist_data->var_refs[]): %u\n",
5687 field->var_ref_idx);
5688
5689 if (field->flags & HIST_FIELD_FL_VAR_REF) {
5690 seq_printf(m, fmt: " name: %s\n", field->name);
5691 seq_printf(m, fmt: " var.idx (into tracing_map_elt.vars[]): %u\n",
5692 field->var.idx);
5693 seq_printf(m, fmt: " var.hist_data: %p\n", field->var.hist_data);
5694 seq_printf(m, fmt: " var_ref_idx (into hist_data->var_refs[]): %u\n",
5695 field->var_ref_idx);
5696 if (field->system)
5697 seq_printf(m, fmt: " system: %s\n", field->system);
5698 if (field->event_name)
5699 seq_printf(m, fmt: " event_name: %s\n", field->event_name);
5700 }
5701
5702 seq_printf(m, fmt: " type: %s\n", field->type);
5703 seq_printf(m, fmt: " size: %u\n", field->size);
5704 seq_printf(m, fmt: " is_signed: %u\n", field->is_signed);
5705
5706 return 0;
5707}
5708
5709static int field_var_debug_show(struct seq_file *m,
5710 struct field_var *field_var, unsigned int i,
5711 bool save_vars)
5712{
5713 const char *vars_name = save_vars ? "save_vars" : "field_vars";
5714 struct hist_field *field;
5715 int ret = 0;
5716
5717 seq_printf(m, fmt: "\n hist_data->%s[%d]:\n", vars_name, i);
5718
5719 field = field_var->var;
5720
5721 seq_printf(m, fmt: "\n %s[%d].var:\n", vars_name, i);
5722
5723 hist_field_debug_show_flags(m, flags: field->flags);
5724 seq_printf(m, fmt: " var.name: %s\n", field->var.name);
5725 seq_printf(m, fmt: " var.idx (into tracing_map_elt.vars[]): %u\n",
5726 field->var.idx);
5727
5728 field = field_var->val;
5729
5730 seq_printf(m, fmt: "\n %s[%d].val:\n", vars_name, i);
5731 if (field->field)
5732 seq_printf(m, fmt: " ftrace_event_field name: %s\n",
5733 field->field->name);
5734 else {
5735 ret = -EINVAL;
5736 goto out;
5737 }
5738
5739 seq_printf(m, fmt: " type: %s\n", field->type);
5740 seq_printf(m, fmt: " size: %u\n", field->size);
5741 seq_printf(m, fmt: " is_signed: %u\n", field->is_signed);
5742out:
5743 return ret;
5744}
5745
5746static int hist_action_debug_show(struct seq_file *m,
5747 struct action_data *data, int i)
5748{
5749 int ret = 0;
5750
5751 if (data->handler == HANDLER_ONMAX ||
5752 data->handler == HANDLER_ONCHANGE) {
5753 seq_printf(m, fmt: "\n hist_data->actions[%d].track_data.var_ref:\n", i);
5754 ret = hist_field_debug_show(m, field: data->track_data.var_ref,
5755 flags: HIST_FIELD_FL_VAR_REF);
5756 if (ret)
5757 goto out;
5758
5759 seq_printf(m, fmt: "\n hist_data->actions[%d].track_data.track_var:\n", i);
5760 ret = hist_field_debug_show(m, field: data->track_data.track_var,
5761 flags: HIST_FIELD_FL_VAR);
5762 if (ret)
5763 goto out;
5764 }
5765
5766 if (data->handler == HANDLER_ONMATCH) {
5767 seq_printf(m, fmt: "\n hist_data->actions[%d].match_data.event_system: %s\n",
5768 i, data->match_data.event_system);
5769 seq_printf(m, fmt: " hist_data->actions[%d].match_data.event: %s\n",
5770 i, data->match_data.event);
5771 }
5772out:
5773 return ret;
5774}
5775
5776static int hist_actions_debug_show(struct seq_file *m,
5777 struct hist_trigger_data *hist_data)
5778{
5779 int i, ret = 0;
5780
5781 if (hist_data->n_actions)
5782 seq_puts(m, s: "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
5783
5784 for (i = 0; i < hist_data->n_actions; i++) {
5785 struct action_data *action = hist_data->actions[i];
5786
5787 ret = hist_action_debug_show(m, data: action, i);
5788 if (ret)
5789 goto out;
5790 }
5791
5792 if (hist_data->n_save_vars)
5793 seq_puts(m, s: "\n save action variables (save() params):\n");
5794
5795 for (i = 0; i < hist_data->n_save_vars; i++) {
5796 ret = field_var_debug_show(m, field_var: hist_data->save_vars[i], i, save_vars: true);
5797 if (ret)
5798 goto out;
5799 }
5800out:
5801 return ret;
5802}
5803
5804static void hist_trigger_debug_show(struct seq_file *m,
5805 struct event_trigger_data *data, int n)
5806{
5807 struct hist_trigger_data *hist_data;
5808 int i, ret;
5809
5810 if (n > 0)
5811 seq_puts(m, s: "\n\n");
5812
5813 seq_puts(m, s: "# event histogram\n#\n# trigger info: ");
5814 data->ops->print(m, data);
5815 seq_puts(m, s: "#\n\n");
5816
5817 hist_data = data->private_data;
5818
5819 seq_printf(m, fmt: "hist_data: %p\n\n", hist_data);
5820 seq_printf(m, fmt: " n_vals: %u\n", hist_data->n_vals);
5821 seq_printf(m, fmt: " n_keys: %u\n", hist_data->n_keys);
5822 seq_printf(m, fmt: " n_fields: %u\n", hist_data->n_fields);
5823
5824 seq_puts(m, s: "\n val fields:\n\n");
5825
5826 seq_puts(m, s: " hist_data->fields[0]:\n");
5827 ret = hist_field_debug_show(m, field: hist_data->fields[0],
5828 flags: HIST_FIELD_FL_HITCOUNT);
5829 if (ret)
5830 return;
5831
5832 for (i = 1; i < hist_data->n_vals; i++) {
5833 seq_printf(m, fmt: "\n hist_data->fields[%d]:\n", i);
5834 ret = hist_field_debug_show(m, field: hist_data->fields[i], flags: 0);
5835 if (ret)
5836 return;
5837 }
5838
5839 seq_puts(m, s: "\n key fields:\n");
5840
5841 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
5842 seq_printf(m, fmt: "\n hist_data->fields[%d]:\n", i);
5843 ret = hist_field_debug_show(m, field: hist_data->fields[i],
5844 flags: HIST_FIELD_FL_KEY);
5845 if (ret)
5846 return;
5847 }
5848
5849 if (hist_data->n_var_refs)
5850 seq_puts(m, s: "\n variable reference fields:\n");
5851
5852 for (i = 0; i < hist_data->n_var_refs; i++) {
5853 seq_printf(m, fmt: "\n hist_data->var_refs[%d]:\n", i);
5854 ret = hist_field_debug_show(m, field: hist_data->var_refs[i],
5855 flags: HIST_FIELD_FL_VAR_REF);
5856 if (ret)
5857 return;
5858 }
5859
5860 if (hist_data->n_field_vars)
5861 seq_puts(m, s: "\n field variables:\n");
5862
5863 for (i = 0; i < hist_data->n_field_vars; i++) {
5864 ret = field_var_debug_show(m, field_var: hist_data->field_vars[i], i, save_vars: false);
5865 if (ret)
5866 return;
5867 }
5868
5869 ret = hist_actions_debug_show(m, hist_data);
5870 if (ret)
5871 return;
5872}
5873
5874static int hist_debug_show(struct seq_file *m, void *v)
5875{
5876 struct event_trigger_data *data;
5877 struct trace_event_file *event_file;
5878 int n = 0, ret = 0;
5879
5880 mutex_lock(&event_mutex);
5881
5882 event_file = event_file_data(filp: m->private);
5883 if (unlikely(!event_file)) {
5884 ret = -ENODEV;
5885 goto out_unlock;
5886 }
5887
5888 list_for_each_entry(data, &event_file->triggers, list) {
5889 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5890 hist_trigger_debug_show(m, data, n: n++);
5891 }
5892
5893 out_unlock:
5894 mutex_unlock(lock: &event_mutex);
5895
5896 return ret;
5897}
5898
5899static int event_hist_debug_open(struct inode *inode, struct file *file)
5900{
5901 int ret;
5902
5903 ret = security_locked_down(what: LOCKDOWN_TRACEFS);
5904 if (ret)
5905 return ret;
5906
5907 return single_open(file, hist_debug_show, file);
5908}
5909
5910const struct file_operations event_hist_debug_fops = {
5911 .open = event_hist_debug_open,
5912 .read = seq_read,
5913 .llseek = seq_lseek,
5914 .release = single_release,
5915};
5916#endif
5917
5918static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5919{
5920 const char *field_name = hist_field_name(field: hist_field, level: 0);
5921
5922 if (hist_field->var.name)
5923 seq_printf(m, fmt: "%s=", hist_field->var.name);
5924
5925 if (hist_field->flags & HIST_FIELD_FL_CPU)
5926 seq_puts(m, s: "common_cpu");
5927 else if (hist_field->flags & HIST_FIELD_FL_CONST)
5928 seq_printf(m, fmt: "%llu", hist_field->constant);
5929 else if (field_name) {
5930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5931 hist_field->flags & HIST_FIELD_FL_ALIAS)
5932 seq_putc(m, c: '$');
5933 seq_printf(m, fmt: "%s", field_name);
5934 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5935 seq_puts(m, s: "common_timestamp");
5936
5937 if (hist_field->flags) {
5938 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5939 !(hist_field->flags & HIST_FIELD_FL_EXPR) &&
5940 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) {
5941 const char *flags = get_hist_field_flags(hist_field);
5942
5943 if (flags)
5944 seq_printf(m, fmt: ".%s", flags);
5945 }
5946 }
5947 if (hist_field->buckets)
5948 seq_printf(m, fmt: "=%ld", hist_field->buckets);
5949}
5950
5951static int event_hist_trigger_print(struct seq_file *m,
5952 struct event_trigger_data *data)
5953{
5954 struct hist_trigger_data *hist_data = data->private_data;
5955 struct hist_field *field;
5956 bool have_var = false;
5957 bool show_val = false;
5958 unsigned int i;
5959
5960 seq_puts(m, HIST_PREFIX);
5961
5962 if (data->name)
5963 seq_printf(m, fmt: "%s:", data->name);
5964
5965 seq_puts(m, s: "keys=");
5966
5967 for_each_hist_key_field(i, hist_data) {
5968 field = hist_data->fields[i];
5969
5970 if (i > hist_data->n_vals)
5971 seq_puts(m, s: ",");
5972
5973 if (field->flags & HIST_FIELD_FL_STACKTRACE) {
5974 if (field->field)
5975 seq_printf(m, fmt: "%s.stacktrace", field->field->name);
5976 else
5977 seq_puts(m, s: "common_stacktrace");
5978 } else
5979 hist_field_print(m, hist_field: field);
5980 }
5981
5982 seq_puts(m, s: ":vals=");
5983
5984 for_each_hist_val_field(i, hist_data) {
5985 field = hist_data->fields[i];
5986 if (field->flags & HIST_FIELD_FL_VAR) {
5987 have_var = true;
5988 continue;
5989 }
5990
5991 if (i == HITCOUNT_IDX) {
5992 if (hist_data->attrs->no_hitcount)
5993 continue;
5994 seq_puts(m, s: "hitcount");
5995 } else {
5996 if (show_val)
5997 seq_puts(m, s: ",");
5998 hist_field_print(m, hist_field: field);
5999 }
6000 show_val = true;
6001 }
6002
6003 if (have_var) {
6004 unsigned int n = 0;
6005
6006 seq_puts(m, s: ":");
6007
6008 for_each_hist_val_field(i, hist_data) {
6009 field = hist_data->fields[i];
6010
6011 if (field->flags & HIST_FIELD_FL_VAR) {
6012 if (n++)
6013 seq_puts(m, s: ",");
6014 hist_field_print(m, hist_field: field);
6015 }
6016 }
6017 }
6018
6019 seq_puts(m, s: ":sort=");
6020
6021 for (i = 0; i < hist_data->n_sort_keys; i++) {
6022 struct tracing_map_sort_key *sort_key;
6023 unsigned int idx, first_key_idx;
6024
6025 /* skip VAR vals */
6026 first_key_idx = hist_data->n_vals - hist_data->n_vars;
6027
6028 sort_key = &hist_data->sort_keys[i];
6029 idx = sort_key->field_idx;
6030
6031 if (WARN_ON(idx >= HIST_FIELDS_MAX))
6032 return -EINVAL;
6033
6034 if (i > 0)
6035 seq_puts(m, s: ",");
6036
6037 if (idx == HITCOUNT_IDX)
6038 seq_puts(m, s: "hitcount");
6039 else {
6040 if (idx >= first_key_idx)
6041 idx += hist_data->n_vars;
6042 hist_field_print(m, hist_field: hist_data->fields[idx]);
6043 }
6044
6045 if (sort_key->descending)
6046 seq_puts(m, s: ".descending");
6047 }
6048 seq_printf(m, fmt: ":size=%u", (1 << hist_data->map->map_bits));
6049 if (hist_data->enable_timestamps)
6050 seq_printf(m, fmt: ":clock=%s", hist_data->attrs->clock);
6051 if (hist_data->attrs->no_hitcount)
6052 seq_puts(m, s: ":nohitcount");
6053
6054 print_actions_spec(m, hist_data);
6055
6056 if (data->filter_str)
6057 seq_printf(m, fmt: " if %s", data->filter_str);
6058
6059 if (data->paused)
6060 seq_puts(m, s: " [paused]");
6061 else
6062 seq_puts(m, s: " [active]");
6063
6064 seq_putc(m, c: '\n');
6065
6066 return 0;
6067}
6068
6069static int event_hist_trigger_init(struct event_trigger_data *data)
6070{
6071 struct hist_trigger_data *hist_data = data->private_data;
6072
6073 if (!data->ref && hist_data->attrs->name)
6074 save_named_trigger(name: hist_data->attrs->name, data);
6075
6076 data->ref++;
6077
6078 return 0;
6079}
6080
6081static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
6082{
6083 struct trace_event_file *file;
6084 unsigned int i;
6085 char *cmd;
6086 int ret;
6087
6088 for (i = 0; i < hist_data->n_field_var_hists; i++) {
6089 file = hist_data->field_var_hists[i]->hist_data->event_file;
6090 cmd = hist_data->field_var_hists[i]->cmd;
6091 ret = event_hist_trigger_parse(cmd_ops: &trigger_hist_cmd, file,
6092 glob: "!hist", cmd: "hist", param_and_filter: cmd);
6093 WARN_ON_ONCE(ret < 0);
6094 }
6095}
6096
6097static void event_hist_trigger_free(struct event_trigger_data *data)
6098{
6099 struct hist_trigger_data *hist_data = data->private_data;
6100
6101 if (WARN_ON_ONCE(data->ref <= 0))
6102 return;
6103
6104 data->ref--;
6105 if (!data->ref) {
6106 if (data->name)
6107 del_named_trigger(data);
6108
6109 trigger_data_free(data);
6110
6111 remove_hist_vars(hist_data);
6112
6113 unregister_field_var_hists(hist_data);
6114
6115 destroy_hist_data(hist_data);
6116 }
6117}
6118
6119static struct event_trigger_ops event_hist_trigger_ops = {
6120 .trigger = event_hist_trigger,
6121 .print = event_hist_trigger_print,
6122 .init = event_hist_trigger_init,
6123 .free = event_hist_trigger_free,
6124};
6125
6126static int event_hist_trigger_named_init(struct event_trigger_data *data)
6127{
6128 data->ref++;
6129
6130 save_named_trigger(name: data->named_data->name, data);
6131
6132 event_hist_trigger_init(data: data->named_data);
6133
6134 return 0;
6135}
6136
6137static void event_hist_trigger_named_free(struct event_trigger_data *data)
6138{
6139 if (WARN_ON_ONCE(data->ref <= 0))
6140 return;
6141
6142 event_hist_trigger_free(data: data->named_data);
6143
6144 data->ref--;
6145 if (!data->ref) {
6146 del_named_trigger(data);
6147 trigger_data_free(data);
6148 }
6149}
6150
6151static struct event_trigger_ops event_hist_trigger_named_ops = {
6152 .trigger = event_hist_trigger,
6153 .print = event_hist_trigger_print,
6154 .init = event_hist_trigger_named_init,
6155 .free = event_hist_trigger_named_free,
6156};
6157
6158static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
6159 char *param)
6160{
6161 return &event_hist_trigger_ops;
6162}
6163
6164static void hist_clear(struct event_trigger_data *data)
6165{
6166 struct hist_trigger_data *hist_data = data->private_data;
6167
6168 if (data->name)
6169 pause_named_trigger(data);
6170
6171 tracepoint_synchronize_unregister();
6172
6173 tracing_map_clear(map: hist_data->map);
6174
6175 if (data->name)
6176 unpause_named_trigger(data);
6177}
6178
6179static bool compatible_field(struct ftrace_event_field *field,
6180 struct ftrace_event_field *test_field)
6181{
6182 if (field == test_field)
6183 return true;
6184 if (field == NULL || test_field == NULL)
6185 return false;
6186 if (strcmp(field->name, test_field->name) != 0)
6187 return false;
6188 if (strcmp(field->type, test_field->type) != 0)
6189 return false;
6190 if (field->size != test_field->size)
6191 return false;
6192 if (field->is_signed != test_field->is_signed)
6193 return false;
6194
6195 return true;
6196}
6197
6198static bool hist_trigger_match(struct event_trigger_data *data,
6199 struct event_trigger_data *data_test,
6200 struct event_trigger_data *named_data,
6201 bool ignore_filter)
6202{
6203 struct tracing_map_sort_key *sort_key, *sort_key_test;
6204 struct hist_trigger_data *hist_data, *hist_data_test;
6205 struct hist_field *key_field, *key_field_test;
6206 unsigned int i;
6207
6208 if (named_data && (named_data != data_test) &&
6209 (named_data != data_test->named_data))
6210 return false;
6211
6212 if (!named_data && is_named_trigger(test: data_test))
6213 return false;
6214
6215 hist_data = data->private_data;
6216 hist_data_test = data_test->private_data;
6217
6218 if (hist_data->n_vals != hist_data_test->n_vals ||
6219 hist_data->n_fields != hist_data_test->n_fields ||
6220 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
6221 return false;
6222
6223 if (!ignore_filter) {
6224 if ((data->filter_str && !data_test->filter_str) ||
6225 (!data->filter_str && data_test->filter_str))
6226 return false;
6227 }
6228
6229 for_each_hist_field(i, hist_data) {
6230 key_field = hist_data->fields[i];
6231 key_field_test = hist_data_test->fields[i];
6232
6233 if (key_field->flags != key_field_test->flags)
6234 return false;
6235 if (!compatible_field(field: key_field->field, test_field: key_field_test->field))
6236 return false;
6237 if (key_field->offset != key_field_test->offset)
6238 return false;
6239 if (key_field->size != key_field_test->size)
6240 return false;
6241 if (key_field->is_signed != key_field_test->is_signed)
6242 return false;
6243 if (!!key_field->var.name != !!key_field_test->var.name)
6244 return false;
6245 if (key_field->var.name &&
6246 strcmp(key_field->var.name, key_field_test->var.name) != 0)
6247 return false;
6248 }
6249
6250 for (i = 0; i < hist_data->n_sort_keys; i++) {
6251 sort_key = &hist_data->sort_keys[i];
6252 sort_key_test = &hist_data_test->sort_keys[i];
6253
6254 if (sort_key->field_idx != sort_key_test->field_idx ||
6255 sort_key->descending != sort_key_test->descending)
6256 return false;
6257 }
6258
6259 if (!ignore_filter && data->filter_str &&
6260 (strcmp(data->filter_str, data_test->filter_str) != 0))
6261 return false;
6262
6263 if (!actions_match(hist_data, hist_data_test))
6264 return false;
6265
6266 return true;
6267}
6268
6269static bool existing_hist_update_only(char *glob,
6270 struct event_trigger_data *data,
6271 struct trace_event_file *file)
6272{
6273 struct hist_trigger_data *hist_data = data->private_data;
6274 struct event_trigger_data *test, *named_data = NULL;
6275 bool updated = false;
6276
6277 if (!hist_data->attrs->pause && !hist_data->attrs->cont &&
6278 !hist_data->attrs->clear)
6279 goto out;
6280
6281 if (hist_data->attrs->name) {
6282 named_data = find_named_trigger(name: hist_data->attrs->name);
6283 if (named_data) {
6284 if (!hist_trigger_match(data, data_test: named_data, named_data,
6285 ignore_filter: true))
6286 goto out;
6287 }
6288 }
6289
6290 if (hist_data->attrs->name && !named_data)
6291 goto out;
6292
6293 list_for_each_entry(test, &file->triggers, list) {
6294 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6295 if (!hist_trigger_match(data, data_test: test, named_data, ignore_filter: false))
6296 continue;
6297 if (hist_data->attrs->pause)
6298 test->paused = true;
6299 else if (hist_data->attrs->cont)
6300 test->paused = false;
6301 else if (hist_data->attrs->clear)
6302 hist_clear(data: test);
6303 updated = true;
6304 goto out;
6305 }
6306 }
6307 out:
6308 return updated;
6309}
6310
6311static int hist_register_trigger(char *glob,
6312 struct event_trigger_data *data,
6313 struct trace_event_file *file)
6314{
6315 struct hist_trigger_data *hist_data = data->private_data;
6316 struct event_trigger_data *test, *named_data = NULL;
6317 struct trace_array *tr = file->tr;
6318 int ret = 0;
6319
6320 if (hist_data->attrs->name) {
6321 named_data = find_named_trigger(name: hist_data->attrs->name);
6322 if (named_data) {
6323 if (!hist_trigger_match(data, data_test: named_data, named_data,
6324 ignore_filter: true)) {
6325 hist_err(tr, err_type: HIST_ERR_NAMED_MISMATCH, err_pos: errpos(str: hist_data->attrs->name));
6326 ret = -EINVAL;
6327 goto out;
6328 }
6329 }
6330 }
6331
6332 if (hist_data->attrs->name && !named_data)
6333 goto new;
6334
6335 lockdep_assert_held(&event_mutex);
6336
6337 list_for_each_entry(test, &file->triggers, list) {
6338 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6339 if (hist_trigger_match(data, data_test: test, named_data, ignore_filter: false)) {
6340 hist_err(tr, err_type: HIST_ERR_TRIGGER_EEXIST, err_pos: 0);
6341 ret = -EEXIST;
6342 goto out;
6343 }
6344 }
6345 }
6346 new:
6347 if (hist_data->attrs->cont || hist_data->attrs->clear) {
6348 hist_err(tr, err_type: HIST_ERR_TRIGGER_ENOENT_CLEAR, err_pos: 0);
6349 ret = -ENOENT;
6350 goto out;
6351 }
6352
6353 if (hist_data->attrs->pause)
6354 data->paused = true;
6355
6356 if (named_data) {
6357 data->private_data = named_data->private_data;
6358 set_named_trigger_data(data, named_data);
6359 data->ops = &event_hist_trigger_named_ops;
6360 }
6361
6362 if (data->ops->init) {
6363 ret = data->ops->init(data);
6364 if (ret < 0)
6365 goto out;
6366 }
6367
6368 if (hist_data->enable_timestamps) {
6369 char *clock = hist_data->attrs->clock;
6370
6371 ret = tracing_set_clock(tr: file->tr, clockstr: hist_data->attrs->clock);
6372 if (ret) {
6373 hist_err(tr, err_type: HIST_ERR_SET_CLOCK_FAIL, err_pos: errpos(str: clock));
6374 goto out;
6375 }
6376
6377 tracing_set_filter_buffering(tr: file->tr, set: true);
6378 }
6379
6380 if (named_data)
6381 destroy_hist_data(hist_data);
6382 out:
6383 return ret;
6384}
6385
6386static int hist_trigger_enable(struct event_trigger_data *data,
6387 struct trace_event_file *file)
6388{
6389 int ret = 0;
6390
6391 list_add_tail_rcu(new: &data->list, head: &file->triggers);
6392
6393 update_cond_flag(file);
6394
6395 if (trace_event_trigger_enable_disable(file, trigger_enable: 1) < 0) {
6396 list_del_rcu(entry: &data->list);
6397 update_cond_flag(file);
6398 ret--;
6399 }
6400
6401 return ret;
6402}
6403
6404static bool have_hist_trigger_match(struct event_trigger_data *data,
6405 struct trace_event_file *file)
6406{
6407 struct hist_trigger_data *hist_data = data->private_data;
6408 struct event_trigger_data *test, *named_data = NULL;
6409 bool match = false;
6410
6411 lockdep_assert_held(&event_mutex);
6412
6413 if (hist_data->attrs->name)
6414 named_data = find_named_trigger(name: hist_data->attrs->name);
6415
6416 list_for_each_entry(test, &file->triggers, list) {
6417 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6418 if (hist_trigger_match(data, data_test: test, named_data, ignore_filter: false)) {
6419 match = true;
6420 break;
6421 }
6422 }
6423 }
6424
6425 return match;
6426}
6427
6428static bool hist_trigger_check_refs(struct event_trigger_data *data,
6429 struct trace_event_file *file)
6430{
6431 struct hist_trigger_data *hist_data = data->private_data;
6432 struct event_trigger_data *test, *named_data = NULL;
6433
6434 lockdep_assert_held(&event_mutex);
6435
6436 if (hist_data->attrs->name)
6437 named_data = find_named_trigger(name: hist_data->attrs->name);
6438
6439 list_for_each_entry(test, &file->triggers, list) {
6440 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6441 if (!hist_trigger_match(data, data_test: test, named_data, ignore_filter: false))
6442 continue;
6443 hist_data = test->private_data;
6444 if (check_var_refs(hist_data))
6445 return true;
6446 break;
6447 }
6448 }
6449
6450 return false;
6451}
6452
6453static void hist_unregister_trigger(char *glob,
6454 struct event_trigger_data *data,
6455 struct trace_event_file *file)
6456{
6457 struct event_trigger_data *test = NULL, *iter, *named_data = NULL;
6458 struct hist_trigger_data *hist_data = data->private_data;
6459
6460 lockdep_assert_held(&event_mutex);
6461
6462 if (hist_data->attrs->name)
6463 named_data = find_named_trigger(name: hist_data->attrs->name);
6464
6465 list_for_each_entry(iter, &file->triggers, list) {
6466 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6467 if (!hist_trigger_match(data, data_test: iter, named_data, ignore_filter: false))
6468 continue;
6469 test = iter;
6470 list_del_rcu(entry: &test->list);
6471 trace_event_trigger_enable_disable(file, trigger_enable: 0);
6472 update_cond_flag(file);
6473 break;
6474 }
6475 }
6476
6477 if (test && test->ops->free)
6478 test->ops->free(test);
6479
6480 if (hist_data->enable_timestamps) {
6481 if (!hist_data->remove || test)
6482 tracing_set_filter_buffering(tr: file->tr, set: false);
6483 }
6484}
6485
6486static bool hist_file_check_refs(struct trace_event_file *file)
6487{
6488 struct hist_trigger_data *hist_data;
6489 struct event_trigger_data *test;
6490
6491 lockdep_assert_held(&event_mutex);
6492
6493 list_for_each_entry(test, &file->triggers, list) {
6494 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6495 hist_data = test->private_data;
6496 if (check_var_refs(hist_data))
6497 return true;
6498 }
6499 }
6500
6501 return false;
6502}
6503
6504static void hist_unreg_all(struct trace_event_file *file)
6505{
6506 struct event_trigger_data *test, *n;
6507 struct hist_trigger_data *hist_data;
6508 struct synth_event *se;
6509 const char *se_name;
6510
6511 lockdep_assert_held(&event_mutex);
6512
6513 if (hist_file_check_refs(file))
6514 return;
6515
6516 list_for_each_entry_safe(test, n, &file->triggers, list) {
6517 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6518 hist_data = test->private_data;
6519 list_del_rcu(entry: &test->list);
6520 trace_event_trigger_enable_disable(file, trigger_enable: 0);
6521
6522 se_name = trace_event_name(call: file->event_call);
6523 se = find_synth_event(name: se_name);
6524 if (se)
6525 se->ref--;
6526
6527 update_cond_flag(file);
6528 if (hist_data->enable_timestamps)
6529 tracing_set_filter_buffering(tr: file->tr, set: false);
6530 if (test->ops->free)
6531 test->ops->free(test);
6532 }
6533 }
6534}
6535
6536static int event_hist_trigger_parse(struct event_command *cmd_ops,
6537 struct trace_event_file *file,
6538 char *glob, char *cmd,
6539 char *param_and_filter)
6540{
6541 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
6542 struct event_trigger_data *trigger_data;
6543 struct hist_trigger_attrs *attrs;
6544 struct hist_trigger_data *hist_data;
6545 char *param, *filter, *p, *start;
6546 struct synth_event *se;
6547 const char *se_name;
6548 bool remove;
6549 int ret = 0;
6550
6551 lockdep_assert_held(&event_mutex);
6552
6553 if (WARN_ON(!glob))
6554 return -EINVAL;
6555
6556 if (glob[0]) {
6557 hist_err_clear();
6558 last_cmd_set(file, str: param_and_filter);
6559 }
6560
6561 remove = event_trigger_check_remove(glob);
6562
6563 if (event_trigger_empty_param(param: param_and_filter))
6564 return -EINVAL;
6565
6566 /*
6567 * separate the trigger from the filter (k:v [if filter])
6568 * allowing for whitespace in the trigger
6569 */
6570 p = param = param_and_filter;
6571 do {
6572 p = strstr(p, "if");
6573 if (!p)
6574 break;
6575 if (p == param_and_filter)
6576 return -EINVAL;
6577 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
6578 p++;
6579 continue;
6580 }
6581 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1)
6582 return -EINVAL;
6583 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
6584 p++;
6585 continue;
6586 }
6587 break;
6588 } while (1);
6589
6590 if (!p)
6591 filter = NULL;
6592 else {
6593 *(p - 1) = '\0';
6594 filter = strstrip(str: p);
6595 param = strstrip(str: param);
6596 }
6597
6598 /*
6599 * To simplify arithmetic expression parsing, replace occurrences of
6600 * '.sym-offset' modifier with '.symXoffset'
6601 */
6602 start = strstr(param, ".sym-offset");
6603 while (start) {
6604 *(start + 4) = 'X';
6605 start = strstr(start + 11, ".sym-offset");
6606 }
6607
6608 attrs = parse_hist_trigger_attrs(tr: file->tr, trigger_str: param);
6609 if (IS_ERR(ptr: attrs))
6610 return PTR_ERR(ptr: attrs);
6611
6612 if (attrs->map_bits)
6613 hist_trigger_bits = attrs->map_bits;
6614
6615 hist_data = create_hist_data(map_bits: hist_trigger_bits, attrs, file, remove);
6616 if (IS_ERR(ptr: hist_data)) {
6617 destroy_hist_trigger_attrs(attrs);
6618 return PTR_ERR(ptr: hist_data);
6619 }
6620
6621 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, private_data: hist_data);
6622 if (!trigger_data) {
6623 ret = -ENOMEM;
6624 goto out_free;
6625 }
6626
6627 ret = event_trigger_set_filter(cmd_ops, file, param: filter, trigger_data);
6628 if (ret < 0)
6629 goto out_free;
6630
6631 if (remove) {
6632 if (!have_hist_trigger_match(data: trigger_data, file))
6633 goto out_free;
6634
6635 if (hist_trigger_check_refs(data: trigger_data, file)) {
6636 ret = -EBUSY;
6637 goto out_free;
6638 }
6639
6640 event_trigger_unregister(cmd_ops, file, glob: glob+1, trigger_data);
6641 se_name = trace_event_name(call: file->event_call);
6642 se = find_synth_event(name: se_name);
6643 if (se)
6644 se->ref--;
6645 ret = 0;
6646 goto out_free;
6647 }
6648
6649 if (existing_hist_update_only(glob, data: trigger_data, file))
6650 goto out_free;
6651
6652 ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
6653 if (ret < 0)
6654 goto out_free;
6655
6656 if (get_named_trigger_data(data: trigger_data))
6657 goto enable;
6658
6659 ret = create_actions(hist_data);
6660 if (ret)
6661 goto out_unreg;
6662
6663 if (has_hist_vars(hist_data) || hist_data->n_var_refs) {
6664 ret = save_hist_vars(hist_data);
6665 if (ret)
6666 goto out_unreg;
6667 }
6668
6669 ret = tracing_map_init(map: hist_data->map);
6670 if (ret)
6671 goto out_unreg;
6672enable:
6673 ret = hist_trigger_enable(data: trigger_data, file);
6674 if (ret)
6675 goto out_unreg;
6676
6677 se_name = trace_event_name(call: file->event_call);
6678 se = find_synth_event(name: se_name);
6679 if (se)
6680 se->ref++;
6681 out:
6682 if (ret == 0 && glob[0])
6683 hist_err_clear();
6684
6685 return ret;
6686 out_unreg:
6687 event_trigger_unregister(cmd_ops, file, glob: glob+1, trigger_data);
6688 out_free:
6689 event_trigger_reset_filter(cmd_ops, trigger_data);
6690
6691 remove_hist_vars(hist_data);
6692
6693 kfree(objp: trigger_data);
6694
6695 destroy_hist_data(hist_data);
6696 goto out;
6697}
6698
6699static struct event_command trigger_hist_cmd = {
6700 .name = "hist",
6701 .trigger_type = ETT_EVENT_HIST,
6702 .flags = EVENT_CMD_FL_NEEDS_REC,
6703 .parse = event_hist_trigger_parse,
6704 .reg = hist_register_trigger,
6705 .unreg = hist_unregister_trigger,
6706 .unreg_all = hist_unreg_all,
6707 .get_trigger_ops = event_hist_get_trigger_ops,
6708 .set_filter = set_trigger_filter,
6709};
6710
6711__init int register_trigger_hist_cmd(void)
6712{
6713 int ret;
6714
6715 ret = register_event_command(cmd: &trigger_hist_cmd);
6716 WARN_ON(ret < 0);
6717
6718 return ret;
6719}
6720
6721static void
6722hist_enable_trigger(struct event_trigger_data *data,
6723 struct trace_buffer *buffer, void *rec,
6724 struct ring_buffer_event *event)
6725{
6726 struct enable_trigger_data *enable_data = data->private_data;
6727 struct event_trigger_data *test;
6728
6729 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
6730 lockdep_is_held(&event_mutex)) {
6731 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6732 if (enable_data->enable)
6733 test->paused = false;
6734 else
6735 test->paused = true;
6736 }
6737 }
6738}
6739
6740static void
6741hist_enable_count_trigger(struct event_trigger_data *data,
6742 struct trace_buffer *buffer, void *rec,
6743 struct ring_buffer_event *event)
6744{
6745 if (!data->count)
6746 return;
6747
6748 if (data->count != -1)
6749 (data->count)--;
6750
6751 hist_enable_trigger(data, buffer, rec, event);
6752}
6753
6754static struct event_trigger_ops hist_enable_trigger_ops = {
6755 .trigger = hist_enable_trigger,
6756 .print = event_enable_trigger_print,
6757 .init = event_trigger_init,
6758 .free = event_enable_trigger_free,
6759};
6760
6761static struct event_trigger_ops hist_enable_count_trigger_ops = {
6762 .trigger = hist_enable_count_trigger,
6763 .print = event_enable_trigger_print,
6764 .init = event_trigger_init,
6765 .free = event_enable_trigger_free,
6766};
6767
6768static struct event_trigger_ops hist_disable_trigger_ops = {
6769 .trigger = hist_enable_trigger,
6770 .print = event_enable_trigger_print,
6771 .init = event_trigger_init,
6772 .free = event_enable_trigger_free,
6773};
6774
6775static struct event_trigger_ops hist_disable_count_trigger_ops = {
6776 .trigger = hist_enable_count_trigger,
6777 .print = event_enable_trigger_print,
6778 .init = event_trigger_init,
6779 .free = event_enable_trigger_free,
6780};
6781
6782static struct event_trigger_ops *
6783hist_enable_get_trigger_ops(char *cmd, char *param)
6784{
6785 struct event_trigger_ops *ops;
6786 bool enable;
6787
6788 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
6789
6790 if (enable)
6791 ops = param ? &hist_enable_count_trigger_ops :
6792 &hist_enable_trigger_ops;
6793 else
6794 ops = param ? &hist_disable_count_trigger_ops :
6795 &hist_disable_trigger_ops;
6796
6797 return ops;
6798}
6799
6800static void hist_enable_unreg_all(struct trace_event_file *file)
6801{
6802 struct event_trigger_data *test, *n;
6803
6804 list_for_each_entry_safe(test, n, &file->triggers, list) {
6805 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
6806 list_del_rcu(entry: &test->list);
6807 update_cond_flag(file);
6808 trace_event_trigger_enable_disable(file, trigger_enable: 0);
6809 if (test->ops->free)
6810 test->ops->free(test);
6811 }
6812 }
6813}
6814
6815static struct event_command trigger_hist_enable_cmd = {
6816 .name = ENABLE_HIST_STR,
6817 .trigger_type = ETT_HIST_ENABLE,
6818 .parse = event_enable_trigger_parse,
6819 .reg = event_enable_register_trigger,
6820 .unreg = event_enable_unregister_trigger,
6821 .unreg_all = hist_enable_unreg_all,
6822 .get_trigger_ops = hist_enable_get_trigger_ops,
6823 .set_filter = set_trigger_filter,
6824};
6825
6826static struct event_command trigger_hist_disable_cmd = {
6827 .name = DISABLE_HIST_STR,
6828 .trigger_type = ETT_HIST_ENABLE,
6829 .parse = event_enable_trigger_parse,
6830 .reg = event_enable_register_trigger,
6831 .unreg = event_enable_unregister_trigger,
6832 .unreg_all = hist_enable_unreg_all,
6833 .get_trigger_ops = hist_enable_get_trigger_ops,
6834 .set_filter = set_trigger_filter,
6835};
6836
6837static __init void unregister_trigger_hist_enable_disable_cmds(void)
6838{
6839 unregister_event_command(cmd: &trigger_hist_enable_cmd);
6840 unregister_event_command(cmd: &trigger_hist_disable_cmd);
6841}
6842
6843__init int register_trigger_hist_enable_disable_cmds(void)
6844{
6845 int ret;
6846
6847 ret = register_event_command(cmd: &trigger_hist_enable_cmd);
6848 if (WARN_ON(ret < 0))
6849 return ret;
6850 ret = register_event_command(cmd: &trigger_hist_disable_cmd);
6851 if (WARN_ON(ret < 0))
6852 unregister_trigger_hist_enable_disable_cmds();
6853
6854 return ret;
6855}
6856

source code of linux/kernel/trace/trace_events_hist.c