1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Compare and figure out the top N hottest streams
4 * Copyright (c) 2020, Intel Corporation.
5 * Author: Jin Yao
6 */
7
8#include <inttypes.h>
9#include <stdlib.h>
10#include <linux/zalloc.h>
11#include "debug.h"
12#include "hist.h"
13#include "sort.h"
14#include "stream.h"
15#include "evlist.h"
16
17static void evsel_streams__delete(struct evsel_streams *es, int nr_evsel)
18{
19 for (int i = 0; i < nr_evsel; i++)
20 zfree(&es[i].streams);
21
22 free(es);
23}
24
25void evlist_streams__delete(struct evlist_streams *els)
26{
27 evsel_streams__delete(es: els->ev_streams, nr_evsel: els->nr_evsel);
28 free(els);
29}
30
31static struct evlist_streams *evlist_streams__new(int nr_evsel,
32 int nr_streams_max)
33{
34 struct evlist_streams *els;
35 struct evsel_streams *es;
36
37 els = zalloc(sizeof(*els));
38 if (!els)
39 return NULL;
40
41 es = calloc(nr_evsel, sizeof(struct evsel_streams));
42 if (!es) {
43 free(els);
44 return NULL;
45 }
46
47 for (int i = 0; i < nr_evsel; i++) {
48 struct evsel_streams *s = &es[i];
49
50 s->streams = calloc(nr_streams_max, sizeof(struct stream));
51 if (!s->streams)
52 goto err;
53
54 s->nr_streams_max = nr_streams_max;
55 s->evsel_idx = -1;
56 }
57
58 els->ev_streams = es;
59 els->nr_evsel = nr_evsel;
60 return els;
61
62err:
63 evsel_streams__delete(es, nr_evsel);
64 return NULL;
65}
66
67/*
68 * The cnodes with high hit number are hot callchains.
69 */
70static void evsel_streams__set_hot_cnode(struct evsel_streams *es,
71 struct callchain_node *cnode)
72{
73 int i, idx = 0;
74 u64 hit;
75
76 if (es->nr_streams < es->nr_streams_max) {
77 i = es->nr_streams;
78 es->streams[i].cnode = cnode;
79 es->nr_streams++;
80 return;
81 }
82
83 /*
84 * Considering a few number of hot streams, only use simple
85 * way to find the cnode with smallest hit number and replace.
86 */
87 hit = (es->streams[0].cnode)->hit;
88 for (i = 1; i < es->nr_streams; i++) {
89 if ((es->streams[i].cnode)->hit < hit) {
90 hit = (es->streams[i].cnode)->hit;
91 idx = i;
92 }
93 }
94
95 if (cnode->hit > hit)
96 es->streams[idx].cnode = cnode;
97}
98
99static void update_hot_callchain(struct hist_entry *he,
100 struct evsel_streams *es)
101{
102 struct rb_root *root = &he->sorted_chain;
103 struct rb_node *rb_node = rb_first(root);
104 struct callchain_node *cnode;
105
106 while (rb_node) {
107 cnode = rb_entry(rb_node, struct callchain_node, rb_node);
108 evsel_streams__set_hot_cnode(es, cnode);
109 rb_node = rb_next(rb_node);
110 }
111}
112
113static void init_hot_callchain(struct hists *hists, struct evsel_streams *es)
114{
115 struct rb_node *next = rb_first_cached(&hists->entries);
116
117 while (next) {
118 struct hist_entry *he;
119
120 he = rb_entry(next, struct hist_entry, rb_node);
121 update_hot_callchain(he, es);
122 next = rb_next(&he->rb_node);
123 }
124
125 es->streams_hits = callchain_total_hits(hists);
126}
127
128static int evlist__init_callchain_streams(struct evlist *evlist,
129 struct evlist_streams *els)
130{
131 struct evsel_streams *es = els->ev_streams;
132 struct evsel *pos;
133 int i = 0;
134
135 BUG_ON(els->nr_evsel < evlist->core.nr_entries);
136
137 evlist__for_each_entry(evlist, pos) {
138 struct hists *hists = evsel__hists(evsel: pos);
139
140 hists__output_resort(hists, NULL);
141 init_hot_callchain(hists, es: &es[i]);
142 es[i].evsel_idx = pos->core.idx;
143 i++;
144 }
145
146 return 0;
147}
148
149struct evlist_streams *evlist__create_streams(struct evlist *evlist,
150 int nr_streams_max)
151{
152 int nr_evsel = evlist->core.nr_entries, ret = -1;
153 struct evlist_streams *els = evlist_streams__new(nr_evsel,
154 nr_streams_max);
155
156 if (!els)
157 return NULL;
158
159 ret = evlist__init_callchain_streams(evlist, els);
160 if (ret) {
161 evlist_streams__delete(els);
162 return NULL;
163 }
164
165 return els;
166}
167
168struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,
169 int evsel_idx)
170{
171 struct evsel_streams *es = els->ev_streams;
172
173 for (int i = 0; i < els->nr_evsel; i++) {
174 if (es[i].evsel_idx == evsel_idx)
175 return &es[i];
176 }
177
178 return NULL;
179}
180
181static struct stream *stream__callchain_match(struct stream *base_stream,
182 struct evsel_streams *es_pair)
183{
184 for (int i = 0; i < es_pair->nr_streams; i++) {
185 struct stream *pair_stream = &es_pair->streams[i];
186
187 if (callchain_cnode_matched(base_cnode: base_stream->cnode,
188 pair_cnode: pair_stream->cnode)) {
189 return pair_stream;
190 }
191 }
192
193 return NULL;
194}
195
196static struct stream *stream__match(struct stream *base_stream,
197 struct evsel_streams *es_pair)
198{
199 return stream__callchain_match(base_stream, es_pair);
200}
201
202static void stream__link(struct stream *base_stream, struct stream *pair_stream)
203{
204 base_stream->pair_cnode = pair_stream->cnode;
205 pair_stream->pair_cnode = base_stream->cnode;
206}
207
208void evsel_streams__match(struct evsel_streams *es_base,
209 struct evsel_streams *es_pair)
210{
211 for (int i = 0; i < es_base->nr_streams; i++) {
212 struct stream *base_stream = &es_base->streams[i];
213 struct stream *pair_stream;
214
215 pair_stream = stream__match(base_stream, es_pair);
216 if (pair_stream)
217 stream__link(base_stream, pair_stream);
218 }
219}
220
221static void print_callchain_pair(struct stream *base_stream, int idx,
222 struct evsel_streams *es_base,
223 struct evsel_streams *es_pair)
224{
225 struct callchain_node *base_cnode = base_stream->cnode;
226 struct callchain_node *pair_cnode = base_stream->pair_cnode;
227 struct callchain_list *base_chain, *pair_chain;
228 char buf1[512], buf2[512], cbuf1[256], cbuf2[256];
229 char *s1, *s2;
230 double pct;
231
232 printf("\nhot chain pair %d:\n", idx);
233
234 pct = (double)base_cnode->hit / (double)es_base->streams_hits;
235 scnprintf(buf: buf1, size: sizeof(buf1), fmt: "cycles: %ld, hits: %.2f%%",
236 callchain_avg_cycles(cnode: base_cnode), pct * 100.0);
237
238 pct = (double)pair_cnode->hit / (double)es_pair->streams_hits;
239 scnprintf(buf: buf2, size: sizeof(buf2), fmt: "cycles: %ld, hits: %.2f%%",
240 callchain_avg_cycles(cnode: pair_cnode), pct * 100.0);
241
242 printf("%35s\t%35s\n", buf1, buf2);
243
244 printf("%35s\t%35s\n",
245 "---------------------------",
246 "--------------------------");
247
248 pair_chain = list_first_entry(&pair_cnode->val,
249 struct callchain_list,
250 list);
251
252 list_for_each_entry(base_chain, &base_cnode->val, list) {
253 if (&pair_chain->list == &pair_cnode->val)
254 return;
255
256 s1 = callchain_list__sym_name(cl: base_chain, bf: cbuf1, bfsize: sizeof(cbuf1),
257 show_dso: false);
258 s2 = callchain_list__sym_name(cl: pair_chain, bf: cbuf2, bfsize: sizeof(cbuf2),
259 show_dso: false);
260
261 scnprintf(buf: buf1, size: sizeof(buf1), fmt: "%35s\t%35s", s1, s2);
262 printf("%s\n", buf1);
263 pair_chain = list_next_entry(pair_chain, list);
264 }
265}
266
267static void print_stream_callchain(struct stream *stream, int idx,
268 struct evsel_streams *es, bool pair)
269{
270 struct callchain_node *cnode = stream->cnode;
271 struct callchain_list *chain;
272 char buf[512], cbuf[256], *s;
273 double pct;
274
275 printf("\nhot chain %d:\n", idx);
276
277 pct = (double)cnode->hit / (double)es->streams_hits;
278 scnprintf(buf, size: sizeof(buf), fmt: "cycles: %ld, hits: %.2f%%",
279 callchain_avg_cycles(cnode), pct * 100.0);
280
281 if (pair) {
282 printf("%35s\t%35s\n", "", buf);
283 printf("%35s\t%35s\n",
284 "", "--------------------------");
285 } else {
286 printf("%35s\n", buf);
287 printf("%35s\n", "--------------------------");
288 }
289
290 list_for_each_entry(chain, &cnode->val, list) {
291 s = callchain_list__sym_name(cl: chain, bf: cbuf, bfsize: sizeof(cbuf), show_dso: false);
292
293 if (pair)
294 scnprintf(buf, size: sizeof(buf), fmt: "%35s\t%35s", "", s);
295 else
296 scnprintf(buf, size: sizeof(buf), fmt: "%35s", s);
297
298 printf("%s\n", buf);
299 }
300}
301
302static void callchain_streams_report(struct evsel_streams *es_base,
303 struct evsel_streams *es_pair)
304{
305 struct stream *base_stream;
306 int i, idx = 0;
307
308 printf("[ Matched hot streams ]\n");
309 for (i = 0; i < es_base->nr_streams; i++) {
310 base_stream = &es_base->streams[i];
311 if (base_stream->pair_cnode) {
312 print_callchain_pair(base_stream, idx: ++idx,
313 es_base, es_pair);
314 }
315 }
316
317 idx = 0;
318 printf("\n[ Hot streams in old perf data only ]\n");
319 for (i = 0; i < es_base->nr_streams; i++) {
320 base_stream = &es_base->streams[i];
321 if (!base_stream->pair_cnode) {
322 print_stream_callchain(stream: base_stream, idx: ++idx,
323 es: es_base, pair: false);
324 }
325 }
326
327 idx = 0;
328 printf("\n[ Hot streams in new perf data only ]\n");
329 for (i = 0; i < es_pair->nr_streams; i++) {
330 base_stream = &es_pair->streams[i];
331 if (!base_stream->pair_cnode) {
332 print_stream_callchain(stream: base_stream, idx: ++idx,
333 es: es_pair, pair: true);
334 }
335 }
336}
337
338void evsel_streams__report(struct evsel_streams *es_base,
339 struct evsel_streams *es_pair)
340{
341 return callchain_streams_report(es_base, es_pair);
342}
343

source code of linux/tools/perf/util/stream.c