tools/perf/util/mmap.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2011-2017, Red Hat Inc, Arnaldo Carvalho de Melo <[email protected]>
   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
  27 size_t mmap__mmap_len(struct mmap *map)
  28 {
  29         return perf_mmap__mmap_len(&map->core);
  30 }
  31
  32 int __weak auxtrace_mmap__mmap(struct auxtrace_mmap *mm __maybe_unused,
  33                                struct auxtrace_mmap_params *mp __maybe_unused,
  34                                void *userpg __maybe_unused,
  35                                int fd __maybe_unused)
  36 {
  37         return 0;
  38 }
  39
  40 void __weak auxtrace_mmap__munmap(struct auxtrace_mmap *mm __maybe_unused)
  41 {
  42 }
  43
  44 void __weak auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp __maybe_unused,
  45                                        off_t auxtrace_offset __maybe_unused,
  46                                        unsigned int auxtrace_pages __maybe_unused,
  47                                        bool auxtrace_overwrite __maybe_unused)
  48 {
  49 }
  50
  51 void __weak auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp __maybe_unused,
  52                                           struct evlist *evlist __maybe_unused,
  53                                           int idx __maybe_unused,
  54                                           bool per_cpu __maybe_unused)
  55 {
  56 }
  57
  58 #ifdef HAVE_AIO_SUPPORT
  59 static int perf_mmap__aio_enabled(struct mmap *map)
  60 {
  61         return map->aio.nr_cblocks > 0;
  62 }
  63
  64 #ifdef HAVE_LIBNUMA_SUPPORT
  65 static int perf_mmap__aio_alloc(struct mmap *map, int idx)
  66 {
  67         map->aio.data[idx] = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
  68                                   MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
  69         if (map->aio.data[idx] == MAP_FAILED) {
  70                 map->aio.data[idx] = NULL;
  71                 return -1;
  72         }
  73
  74         return 0;
  75 }
  76
  77 static void perf_mmap__aio_free(struct mmap *map, int idx)
  78 {
  79         if (map->aio.data[idx]) {
  80                 munmap(map->aio.data[idx], mmap__mmap_len(map));
  81                 map->aio.data[idx] = NULL;
  82         }
  83 }
  84
  85 static int perf_mmap__aio_bind(struct mmap *map, int idx, int cpu, int affinity)
  86 {
  87         void *data;
  88         size_t mmap_len;
  89         unsigned long node_mask;
  90
  91         if (affinity != PERF_AFFINITY_SYS && cpu__max_node() > 1) {
  92                 data = map->aio.data[idx];
  93                 mmap_len = mmap__mmap_len(map);
  94                 node_mask = 1UL << cpu__get_node(cpu);
  95                 if (mbind(data, mmap_len, MPOL_BIND, &node_mask, 1, 0)) {
  96                         pr_err("Failed to bind [%p-%p] AIO buffer to node %d: error %m\n",
  97                                 data, data + mmap_len, cpu__get_node(cpu));
  98                         return -1;
  99                 }
 100         }
 101
 102         return 0;
 103 }
 104 #else /* !HAVE_LIBNUMA_SUPPORT */
 105 static int perf_mmap__aio_alloc(struct mmap *map, int idx)
 106 {
 107         map->aio.data[idx] = malloc(mmap__mmap_len(map));
 108         if (map->aio.data[idx] == NULL)
 109                 return -1;
 110
 111         return 0;
 112 }
 113
 114 static void perf_mmap__aio_free(struct mmap *map, int idx)
 115 {
 116         zfree(&(map->aio.data[idx]));
 117 }
 118
 119 static int perf_mmap__aio_bind(struct mmap *map __maybe_unused, int idx __maybe_unused,
 120                 int cpu __maybe_unused, int affinity __maybe_unused)
 121 {
 122         return 0;
 123 }
 124 #endif
 125
 126 static int perf_mmap__aio_mmap(struct mmap *map, struct mmap_params *mp)
 127 {
 128         int delta_max, i, prio, ret;
 129
 130         map->aio.nr_cblocks = mp->nr_cblocks;
 131         if (map->aio.nr_cblocks) {
 132                 map->aio.aiocb = calloc(map->aio.nr_cblocks, sizeof(struct aiocb *));
 133                 if (!map->aio.aiocb) {
 134                         pr_debug2("failed to allocate aiocb for data buffer, error %m\n");
 135                         return -1;
 136                 }
 137                 map->aio.cblocks = calloc(map->aio.nr_cblocks, sizeof(struct aiocb));
 138                 if (!map->aio.cblocks) {
 139                         pr_debug2("failed to allocate cblocks for data buffer, error %m\n");
 140                         return -1;
 141                 }
 142                 map->aio.data = calloc(map->aio.nr_cblocks, sizeof(void *));
 143                 if (!map->aio.data) {
 144                         pr_debug2("failed to allocate data buffer, error %m\n");
 145                         return -1;
 146                 }
 147                 delta_max = sysconf(_SC_AIO_PRIO_DELTA_MAX);
 148                 for (i = 0; i < map->aio.nr_cblocks; ++i) {
 149                         ret = perf_mmap__aio_alloc(map, i);
 150                         if (ret == -1) {
 151                                 pr_debug2("failed to allocate data buffer area, error %m");
 152                                 return -1;
 153                         }
 154                         ret = perf_mmap__aio_bind(map, i, map->core.cpu, mp->affinity);
 155                         if (ret == -1)
 156                                 return -1;
 157                         /*
 158                          * Use cblock.aio_fildes value different from -1
 159                          * to denote started aio write operation on the
 160                          * cblock so it requires explicit record__aio_sync()
 161                          * call prior the cblock may be reused again.
 162                          */
 163                         map->aio.cblocks[i].aio_fildes = -1;
 164                         /*
 165                          * Allocate cblocks with priority delta to have
 166                          * faster aio write system calls because queued requests
 167                          * are kept in separate per-prio queues and adding
 168                          * a new request will iterate thru shorter per-prio
 169                          * list. Blocks with numbers higher than
 170                          *  _SC_AIO_PRIO_DELTA_MAX go with priority 0.
 171                          */
 172                         prio = delta_max - i;
 173                         map->aio.cblocks[i].aio_reqprio = prio >= 0 ? prio : 0;
 174                 }
 175         }
 176
 177         return 0;
 178 }
 179
 180 static void perf_mmap__aio_munmap(struct mmap *map)
 181 {
 182         int i;
 183
 184         for (i = 0; i < map->aio.nr_cblocks; ++i)
 185                 perf_mmap__aio_free(map, i);
 186         if (map->aio.data)
 187                 zfree(&map->aio.data);
 188         zfree(&map->aio.cblocks);
 189         zfree(&map->aio.aiocb);
 190 }
 191 #else /* !HAVE_AIO_SUPPORT */
 192 static int perf_mmap__aio_enabled(struct mmap *map __maybe_unused)
 193 {
 194         return 0;
 195 }
 196
 197 static int perf_mmap__aio_mmap(struct mmap *map __maybe_unused,
 198                                struct mmap_params *mp __maybe_unused)
 199 {
 200         return 0;
 201 }
 202
 203 static void perf_mmap__aio_munmap(struct mmap *map __maybe_unused)
 204 {
 205 }
 206 #endif
 207
 208 void mmap__munmap(struct mmap *map)
 209 {
 210         perf_mmap__aio_munmap(map);
 211         if (map->data != NULL) {
 212                 munmap(map->data, mmap__mmap_len(map));
 213                 map->data = NULL;
 214         }
 215         auxtrace_mmap__munmap(&map->auxtrace_mmap);
 216 }
 217
 218 static void build_node_mask(int node, cpu_set_t *mask)
 219 {
 220         int c, cpu, nr_cpus;
 221         const struct perf_cpu_map *cpu_map = NULL;
 222
 223         cpu_map = cpu_map__online();
 224         if (!cpu_map)
 225                 return;
 226
 227         nr_cpus = perf_cpu_map__nr(cpu_map);
 228         for (c = 0; c < nr_cpus; c++) {
 229                 cpu = cpu_map->map[c]; /* map c index to online cpu index */
 230                 if (cpu__get_node(cpu) == node)
 231                         CPU_SET(cpu, mask);
 232         }
 233 }
 234
 235 static void perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
 236 {
 237         CPU_ZERO(&map->affinity_mask);
 238         if (mp->affinity == PERF_AFFINITY_NODE && cpu__max_node() > 1)
 239                 build_node_mask(cpu__get_node(map->core.cpu), &map->affinity_mask);
 240         else if (mp->affinity == PERF_AFFINITY_CPU)
 241                 CPU_SET(map->core.cpu, &map->affinity_mask);
 242 }
 243
 244 int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, int cpu)
 245 {
 246         if (perf_mmap__mmap(&map->core, &mp->core, fd, cpu)) {
 247                 pr_debug2("failed to mmap perf event ring buffer, error %d\n",
 248                           errno);
 249                 return -1;
 250         }
 251
 252         perf_mmap__setup_affinity_mask(map, mp);
 253
 254         map->core.flush = mp->flush;
 255
 256         map->comp_level = mp->comp_level;
 257
 258         if (map->comp_level && !perf_mmap__aio_enabled(map)) {
 259                 map->data = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
 260                                  MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
 261                 if (map->data == MAP_FAILED) {
 262                         pr_debug2("failed to mmap data buffer, error %d\n",
 263                                         errno);
 264                         map->data = NULL;
 265                         return -1;
 266                 }
 267         }
 268
 269         if (auxtrace_mmap__mmap(&map->auxtrace_mmap,
 270                                 &mp->auxtrace_mp, map->core.base, fd))
 271                 return -1;
 272
 273         return perf_mmap__aio_mmap(map, mp);
 274 }
 275
 276 int perf_mmap__push(struct mmap *md, void *to,
 277                     int push(struct mmap *map, void *to, void *buf, size_t size))
 278 {
 279         u64 head = perf_mmap__read_head(&md->core);
 280         unsigned char *data = md->core.base + page_size;
 281         unsigned long size;
 282         void *buf;
 283         int rc = 0;
 284
 285         rc = perf_mmap__read_init(&md->core);
 286         if (rc < 0)
 287                 return (rc == -EAGAIN) ? 1 : -1;
 288
 289         size = md->core.end - md->core.start;
 290
 291         if ((md->core.start & md->core.mask) + size != (md->core.end & md->core.mask)) {
 292                 buf = &data[md->core.start & md->core.mask];
 293                 size = md->core.mask + 1 - (md->core.start & md->core.mask);
 294                 md->core.start += size;
 295
 296                 if (push(md, to, buf, size) < 0) {
 297                         rc = -1;
 298                         goto out;
 299                 }
 300         }
 301
 302         buf = &data[md->core.start & md->core.mask];
 303         size = md->core.end - md->core.start;
 304         md->core.start += size;
 305
 306         if (push(md, to, buf, size) < 0) {
 307                 rc = -1;
 308                 goto out;
 309         }
 310
 311         md->core.prev = head;
 312         perf_mmap__consume(&md->core);
 313 out:
 314         return rc;
 315 }