1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2011-2017, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
4 *
5 * Parts came from evlist.c builtin-{top,stat,record}.c, see those files for further
6 * copyright notes.
7 */
8
9#include <sys/mman.h>
10#include <inttypes.h>
11#include <asm/bug.h>
12#include <linux/zalloc.h>
13#include <stdlib.h>
14#include <string.h>
15#include <unistd.h> // sysconf()
16#include <perf/mmap.h>
17#ifdef HAVE_LIBNUMA_SUPPORT
18#include <numaif.h>
19#endif
20#include "cpumap.h"
21#include "debug.h"
22#include "event.h"
23#include "mmap.h"
24#include "../perf.h"
25#include <internal/lib.h> /* page_size */
26#include <linux/bitmap.h>
27
28#define MASK_SIZE 1023
29void mmap_cpu_mask__scnprintf(struct mmap_cpu_mask *mask, const char *tag)
30{
31 char buf[MASK_SIZE + 1];
32 size_t len;
33
34 len = bitmap_scnprintf(mask->bits, mask->nbits, buf, MASK_SIZE);
35 buf[len] = '\0';
36 pr_debug("%p: %s mask[%zd]: %s\n", mask, tag, mask->nbits, buf);
37}
38
39size_t mmap__mmap_len(struct mmap *map)
40{
41 return perf_mmap__mmap_len(&map->core);
42}
43
44int __weak auxtrace_mmap__mmap(struct auxtrace_mmap *mm __maybe_unused,
45 struct auxtrace_mmap_params *mp __maybe_unused,
46 void *userpg __maybe_unused,
47 int fd __maybe_unused)
48{
49 return 0;
50}
51
52void __weak auxtrace_mmap__munmap(struct auxtrace_mmap *mm __maybe_unused)
53{
54}
55
56void __weak auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp __maybe_unused,
57 off_t auxtrace_offset __maybe_unused,
58 unsigned int auxtrace_pages __maybe_unused,
59 bool auxtrace_overwrite __maybe_unused)
60{
61}
62
63void __weak auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp __maybe_unused,
64 struct evlist *evlist __maybe_unused,
65 struct evsel *evsel __maybe_unused,
66 int idx __maybe_unused)
67{
68}
69
70#ifdef HAVE_AIO_SUPPORT
71static int perf_mmap__aio_enabled(struct mmap *map)
72{
73 return map->aio.nr_cblocks > 0;
74}
75
76#ifdef HAVE_LIBNUMA_SUPPORT
77static int perf_mmap__aio_alloc(struct mmap *map, int idx)
78{
79 map->aio.data[idx] = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
80 MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
81 if (map->aio.data[idx] == MAP_FAILED) {
82 map->aio.data[idx] = NULL;
83 return -1;
84 }
85
86 return 0;
87}
88
89static void perf_mmap__aio_free(struct mmap *map, int idx)
90{
91 if (map->aio.data[idx]) {
92 munmap(map->aio.data[idx], mmap__mmap_len(map));
93 map->aio.data[idx] = NULL;
94 }
95}
96
97static int perf_mmap__aio_bind(struct mmap *map, int idx, struct perf_cpu cpu, int affinity)
98{
99 void *data;
100 size_t mmap_len;
101 unsigned long *node_mask;
102 unsigned long node_index;
103 int err = 0;
104
105 if (affinity != PERF_AFFINITY_SYS && cpu__max_node() > 1) {
106 data = map->aio.data[idx];
107 mmap_len = mmap__mmap_len(map);
108 node_index = cpu__get_node(cpu);
109 node_mask = bitmap_zalloc(node_index + 1);
110 if (!node_mask) {
111 pr_err("Failed to allocate node mask for mbind: error %m\n");
112 return -1;
113 }
114 __set_bit(node_index, node_mask);
115 if (mbind(data, mmap_len, MPOL_BIND, node_mask, node_index + 1 + 1, 0)) {
116 pr_err("Failed to bind [%p-%p] AIO buffer to node %lu: error %m\n",
117 data, data + mmap_len, node_index);
118 err = -1;
119 }
120 bitmap_free(node_mask);
121 }
122
123 return err;
124}
125#else /* !HAVE_LIBNUMA_SUPPORT */
126static int perf_mmap__aio_alloc(struct mmap *map, int idx)
127{
128 map->aio.data[idx] = malloc(mmap__mmap_len(map));
129 if (map->aio.data[idx] == NULL)
130 return -1;
131
132 return 0;
133}
134
135static void perf_mmap__aio_free(struct mmap *map, int idx)
136{
137 zfree(&(map->aio.data[idx]));
138}
139
140static int perf_mmap__aio_bind(struct mmap *map __maybe_unused, int idx __maybe_unused,
141 struct perf_cpu cpu __maybe_unused, int affinity __maybe_unused)
142{
143 return 0;
144}
145#endif
146
147static int perf_mmap__aio_mmap(struct mmap *map, struct mmap_params *mp)
148{
149 int delta_max, i, prio, ret;
150
151 map->aio.nr_cblocks = mp->nr_cblocks;
152 if (map->aio.nr_cblocks) {
153 map->aio.aiocb = calloc(map->aio.nr_cblocks, sizeof(struct aiocb *));
154 if (!map->aio.aiocb) {
155 pr_debug2("failed to allocate aiocb for data buffer, error %m\n");
156 return -1;
157 }
158 map->aio.cblocks = calloc(map->aio.nr_cblocks, sizeof(struct aiocb));
159 if (!map->aio.cblocks) {
160 pr_debug2("failed to allocate cblocks for data buffer, error %m\n");
161 return -1;
162 }
163 map->aio.data = calloc(map->aio.nr_cblocks, sizeof(void *));
164 if (!map->aio.data) {
165 pr_debug2("failed to allocate data buffer, error %m\n");
166 return -1;
167 }
168 delta_max = sysconf(_SC_AIO_PRIO_DELTA_MAX);
169 for (i = 0; i < map->aio.nr_cblocks; ++i) {
170 ret = perf_mmap__aio_alloc(map, i);
171 if (ret == -1) {
172 pr_debug2("failed to allocate data buffer area, error %m");
173 return -1;
174 }
175 ret = perf_mmap__aio_bind(map, i, map->core.cpu, mp->affinity);
176 if (ret == -1)
177 return -1;
178 /*
179 * Use cblock.aio_fildes value different from -1
180 * to denote started aio write operation on the
181 * cblock so it requires explicit record__aio_sync()
182 * call prior the cblock may be reused again.
183 */
184 map->aio.cblocks[i].aio_fildes = -1;
185 /*
186 * Allocate cblocks with priority delta to have
187 * faster aio write system calls because queued requests
188 * are kept in separate per-prio queues and adding
189 * a new request will iterate thru shorter per-prio
190 * list. Blocks with numbers higher than
191 * _SC_AIO_PRIO_DELTA_MAX go with priority 0.
192 */
193 prio = delta_max - i;
194 map->aio.cblocks[i].aio_reqprio = prio >= 0 ? prio : 0;
195 }
196 }
197
198 return 0;
199}
200
201static void perf_mmap__aio_munmap(struct mmap *map)
202{
203 int i;
204
205 for (i = 0; i < map->aio.nr_cblocks; ++i)
206 perf_mmap__aio_free(map, i);
207 if (map->aio.data)
208 zfree(&map->aio.data);
209 zfree(&map->aio.cblocks);
210 zfree(&map->aio.aiocb);
211}
212#else /* !HAVE_AIO_SUPPORT */
213static int perf_mmap__aio_enabled(struct mmap *map __maybe_unused)
214{
215 return 0;
216}
217
218static int perf_mmap__aio_mmap(struct mmap *map __maybe_unused,
219 struct mmap_params *mp __maybe_unused)
220{
221 return 0;
222}
223
224static void perf_mmap__aio_munmap(struct mmap *map __maybe_unused)
225{
226}
227#endif
228
229void mmap__munmap(struct mmap *map)
230{
231 bitmap_free(bitmap: map->affinity_mask.bits);
232
233#ifndef PYTHON_PERF
234 zstd_fini(&map->zstd_data);
235#endif
236
237 perf_mmap__aio_munmap(map);
238 if (map->data != NULL) {
239 munmap(map->data, mmap__mmap_len(map));
240 map->data = NULL;
241 }
242 auxtrace_mmap__munmap(mm: &map->auxtrace_mmap);
243}
244
245static void build_node_mask(int node, struct mmap_cpu_mask *mask)
246{
247 int idx, nr_cpus;
248 struct perf_cpu cpu;
249 const struct perf_cpu_map *cpu_map = NULL;
250
251 cpu_map = cpu_map__online();
252 if (!cpu_map)
253 return;
254
255 nr_cpus = perf_cpu_map__nr(cpu_map);
256 for (idx = 0; idx < nr_cpus; idx++) {
257 cpu = perf_cpu_map__cpu(cpu_map, idx); /* map c index to online cpu index */
258 if (cpu__get_node(cpu: cpu) == node)
259 __set_bit(cpu.cpu, mask->bits);
260 }
261}
262
263static int perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
264{
265 map->affinity_mask.nbits = cpu__max_cpu().cpu;
266 map->affinity_mask.bits = bitmap_zalloc(map->affinity_mask.nbits);
267 if (!map->affinity_mask.bits)
268 return -1;
269
270 if (mp->affinity == PERF_AFFINITY_NODE && cpu__max_node() > 1)
271 build_node_mask(node: cpu__get_node(cpu: map->core.cpu), mask: &map->affinity_mask);
272 else if (mp->affinity == PERF_AFFINITY_CPU)
273 __set_bit(map->core.cpu.cpu, map->affinity_mask.bits);
274
275 return 0;
276}
277
278int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, struct perf_cpu cpu)
279{
280 if (perf_mmap__mmap(&map->core, &mp->core, fd, cpu)) {
281 pr_debug2("failed to mmap perf event ring buffer, error %d\n",
282 errno);
283 return -1;
284 }
285
286 if (mp->affinity != PERF_AFFINITY_SYS &&
287 perf_mmap__setup_affinity_mask(map, mp)) {
288 pr_debug2("failed to alloc mmap affinity mask, error %d\n",
289 errno);
290 return -1;
291 }
292
293 if (verbose == 2)
294 mmap_cpu_mask__scnprintf(mask: &map->affinity_mask, tag: "mmap");
295
296 map->core.flush = mp->flush;
297
298#ifndef PYTHON_PERF
299 if (zstd_init(&map->zstd_data, mp->comp_level)) {
300 pr_debug2("failed to init mmap compressor, error %d\n", errno);
301 return -1;
302 }
303#endif
304
305 if (mp->comp_level && !perf_mmap__aio_enabled(map)) {
306 map->data = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
307 MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
308 if (map->data == MAP_FAILED) {
309 pr_debug2("failed to mmap data buffer, error %d\n",
310 errno);
311 map->data = NULL;
312 return -1;
313 }
314 }
315
316 if (auxtrace_mmap__mmap(mm: &map->auxtrace_mmap,
317 mp: &mp->auxtrace_mp, userpg: map->core.base, fd))
318 return -1;
319
320 return perf_mmap__aio_mmap(map, mp);
321}
322
323int perf_mmap__push(struct mmap *md, void *to,
324 int push(struct mmap *map, void *to, void *buf, size_t size))
325{
326 u64 head = perf_mmap__read_head(&md->core);
327 unsigned char *data = md->core.base + page_size;
328 unsigned long size;
329 void *buf;
330 int rc = 0;
331
332 rc = perf_mmap__read_init(&md->core);
333 if (rc < 0)
334 return (rc == -EAGAIN) ? 1 : -1;
335
336 size = md->core.end - md->core.start;
337
338 if ((md->core.start & md->core.mask) + size != (md->core.end & md->core.mask)) {
339 buf = &data[md->core.start & md->core.mask];
340 size = md->core.mask + 1 - (md->core.start & md->core.mask);
341 md->core.start += size;
342
343 if (push(md, to, buf, size) < 0) {
344 rc = -1;
345 goto out;
346 }
347 }
348
349 buf = &data[md->core.start & md->core.mask];
350 size = md->core.end - md->core.start;
351 md->core.start += size;
352
353 if (push(md, to, buf, size) < 0) {
354 rc = -1;
355 goto out;
356 }
357
358 md->core.prev = head;
359 perf_mmap__consume(&md->core);
360out:
361 return rc;
362}
363
364int mmap_cpu_mask__duplicate(struct mmap_cpu_mask *original, struct mmap_cpu_mask *clone)
365{
366 clone->nbits = original->nbits;
367 clone->bits = bitmap_zalloc(original->nbits);
368 if (!clone->bits)
369 return -ENOMEM;
370
371 memcpy(clone->bits, original->bits, MMAP_CPU_MASK_BYTES(original));
372 return 0;
373}
374

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