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 <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
  29 void 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
  39 size_t mmap__mmap_len(struct mmap *map)
  40 {
  41         return perf_mmap__mmap_len(&map->core);
  42 }
  43
  44 int __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
  52 void __weak auxtrace_mmap__munmap(struct auxtrace_mmap *mm __maybe_unused)
  53 {
  54 }
  55
  56 void __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
  63 void __weak auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp __maybe_unused,
  64                                           struct evlist *evlist __maybe_unused,
  65                                           int idx __maybe_unused,
  66                                           bool per_cpu __maybe_unused)
  67 {
  68 }
  69
  70 #ifdef HAVE_AIO_SUPPORT
  71 static int perf_mmap__aio_enabled(struct mmap *map)
  72 {
  73         return map->aio.nr_cblocks > 0;
  74 }
  75
  76 #ifdef HAVE_LIBNUMA_SUPPORT
  77 static 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
  89 static 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
  97 static int perf_mmap__aio_bind(struct mmap *map, int idx, int 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 */
 126 static 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
 135 static void perf_mmap__aio_free(struct mmap *map, int idx)
 136 {
 137         zfree(&(map->aio.data[idx]));
 138 }
 139
 140 static int perf_mmap__aio_bind(struct mmap *map __maybe_unused, int idx __maybe_unused,
 141                 int cpu __maybe_unused, int affinity __maybe_unused)
 142 {
 143         return 0;
 144 }
 145 #endif
 146
 147 static 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
 201 static 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 */
 213 static int perf_mmap__aio_enabled(struct mmap *map __maybe_unused)
 214 {
 215         return 0;
 216 }
 217
 218 static int perf_mmap__aio_mmap(struct mmap *map __maybe_unused,
 219                                struct mmap_params *mp __maybe_unused)
 220 {
 221         return 0;
 222 }
 223
 224 static void perf_mmap__aio_munmap(struct mmap *map __maybe_unused)
 225 {
 226 }
 227 #endif
 228
 229 void mmap__munmap(struct mmap *map)
 230 {
 231         bitmap_free(map->affinity_mask.bits);
 232
 233         perf_mmap__aio_munmap(map);
 234         if (map->data != NULL) {
 235                 munmap(map->data, mmap__mmap_len(map));
 236                 map->data = NULL;
 237         }
 238         auxtrace_mmap__munmap(&map->auxtrace_mmap);
 239 }
 240
 241 static void build_node_mask(int node, struct mmap_cpu_mask *mask)
 242 {
 243         int c, cpu, nr_cpus;
 244         const struct perf_cpu_map *cpu_map = NULL;
 245
 246         cpu_map = cpu_map__online();
 247         if (!cpu_map)
 248                 return;
 249
 250         nr_cpus = perf_cpu_map__nr(cpu_map);
 251         for (c = 0; c < nr_cpus; c++) {
 252                 cpu = cpu_map->map[c]; /* map c index to online cpu index */
 253                 if (cpu__get_node(cpu) == node)
 254                         set_bit(cpu, mask->bits);
 255         }
 256 }
 257
 258 static int perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
 259 {
 260         map->affinity_mask.nbits = cpu__max_cpu();
 261         map->affinity_mask.bits = bitmap_zalloc(map->affinity_mask.nbits);
 262         if (!map->affinity_mask.bits)
 263                 return -1;
 264
 265         if (mp->affinity == PERF_AFFINITY_NODE && cpu__max_node() > 1)
 266                 build_node_mask(cpu__get_node(map->core.cpu), &map->affinity_mask);
 267         else if (mp->affinity == PERF_AFFINITY_CPU)
 268                 set_bit(map->core.cpu, map->affinity_mask.bits);
 269
 270         return 0;
 271 }
 272
 273 int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, int cpu)
 274 {
 275         if (perf_mmap__mmap(&map->core, &mp->core, fd, cpu)) {
 276                 pr_debug2("failed to mmap perf event ring buffer, error %d\n",
 277                           errno);
 278                 return -1;
 279         }
 280
 281         if (mp->affinity != PERF_AFFINITY_SYS &&
 282                 perf_mmap__setup_affinity_mask(map, mp)) {
 283                 pr_debug2("failed to alloc mmap affinity mask, error %d\n",
 284                           errno);
 285                 return -1;
 286         }
 287
 288         if (verbose == 2)
 289                 mmap_cpu_mask__scnprintf(&map->affinity_mask, "mmap");
 290
 291         map->core.flush = mp->flush;
 292
 293         map->comp_level = mp->comp_level;
 294
 295         if (map->comp_level && !perf_mmap__aio_enabled(map)) {
 296                 map->data = mmap(NULL, mmap__mmap_len(map), PROT_READ|PROT_WRITE,
 297                                  MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
 298                 if (map->data == MAP_FAILED) {
 299                         pr_debug2("failed to mmap data buffer, error %d\n",
 300                                         errno);
 301                         map->data = NULL;
 302                         return -1;
 303                 }
 304         }
 305
 306         if (auxtrace_mmap__mmap(&map->auxtrace_mmap,
 307                                 &mp->auxtrace_mp, map->core.base, fd))
 308                 return -1;
 309
 310         return perf_mmap__aio_mmap(map, mp);
 311 }
 312
 313 int perf_mmap__push(struct mmap *md, void *to,
 314                     int push(struct mmap *map, void *to, void *buf, size_t size))
 315 {
 316         u64 head = perf_mmap__read_head(&md->core);
 317         unsigned char *data = md->core.base + page_size;
 318         unsigned long size;
 319         void *buf;
 320         int rc = 0;
 321
 322         rc = perf_mmap__read_init(&md->core);
 323         if (rc < 0)
 324                 return (rc == -EAGAIN) ? 1 : -1;
 325
 326         size = md->core.end - md->core.start;
 327
 328         if ((md->core.start & md->core.mask) + size != (md->core.end & md->core.mask)) {
 329                 buf = &data[md->core.start & md->core.mask];
 330                 size = md->core.mask + 1 - (md->core.start & md->core.mask);
 331                 md->core.start += size;
 332
 333                 if (push(md, to, buf, size) < 0) {
 334                         rc = -1;
 335                         goto out;
 336                 }
 337         }
 338
 339         buf = &data[md->core.start & md->core.mask];
 340         size = md->core.end - md->core.start;
 341         md->core.start += size;
 342
 343         if (push(md, to, buf, size) < 0) {
 344                 rc = -1;
 345                 goto out;
 346         }
 347
 348         md->core.prev = head;
 349         perf_mmap__consume(&md->core);
 350 out:
 351         return rc;
 352 }