linux/tools/perf/bench/mem-functions.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * mem-memcpy.c
   4 *
   5 * Simple memcpy() and memset() benchmarks
   6 *
   7 * Written by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
   8 */
   9
  10#include "debug.h"
  11#include "../perf-sys.h"
  12#include <subcmd/parse-options.h>
  13#include "../util/header.h"
  14#include "../util/cloexec.h"
  15#include "../util/string2.h"
  16#include "bench.h"
  17#include "mem-memcpy-arch.h"
  18#include "mem-memset-arch.h"
  19
  20#include <stdio.h>
  21#include <stdlib.h>
  22#include <string.h>
  23#include <unistd.h>
  24#include <sys/time.h>
  25#include <errno.h>
  26#include <linux/time64.h>
  27#include <linux/zalloc.h>
  28
  29#define K 1024
  30
  31static const char       *size_str       = "1MB";
  32static const char       *function_str   = "all";
  33static int              nr_loops        = 1;
  34static bool             use_cycles;
  35static int              cycles_fd;
  36
  37static const struct option options[] = {
  38        OPT_STRING('s', "size", &size_str, "1MB",
  39                    "Specify the size of the memory buffers. "
  40                    "Available units: B, KB, MB, GB and TB (case insensitive)"),
  41
  42        OPT_STRING('f', "function", &function_str, "all",
  43                    "Specify the function to run, \"all\" runs all available functions, \"help\" lists them"),
  44
  45        OPT_INTEGER('l', "nr_loops", &nr_loops,
  46                    "Specify the number of loops to run. (default: 1)"),
  47
  48        OPT_BOOLEAN('c', "cycles", &use_cycles,
  49                    "Use a cycles event instead of gettimeofday() to measure performance"),
  50
  51        OPT_END()
  52};
  53
  54typedef void *(*memcpy_t)(void *, const void *, size_t);
  55typedef void *(*memset_t)(void *, int, size_t);
  56
  57struct function {
  58        const char *name;
  59        const char *desc;
  60        union {
  61                memcpy_t memcpy;
  62                memset_t memset;
  63        } fn;
  64};
  65
  66static struct perf_event_attr cycle_attr = {
  67        .type           = PERF_TYPE_HARDWARE,
  68        .config         = PERF_COUNT_HW_CPU_CYCLES
  69};
  70
  71static int init_cycles(void)
  72{
  73        cycles_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1, perf_event_open_cloexec_flag());
  74
  75        if (cycles_fd < 0 && errno == ENOSYS) {
  76                pr_debug("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
  77                return -1;
  78        }
  79
  80        return cycles_fd;
  81}
  82
  83static u64 get_cycles(void)
  84{
  85        int ret;
  86        u64 clk;
  87
  88        ret = read(cycles_fd, &clk, sizeof(u64));
  89        BUG_ON(ret != sizeof(u64));
  90
  91        return clk;
  92}
  93
  94static double timeval2double(struct timeval *ts)
  95{
  96        return (double)ts->tv_sec + (double)ts->tv_usec / (double)USEC_PER_SEC;
  97}
  98
  99#define print_bps(x) do {                                               \
 100                if (x < K)                                              \
 101                        printf(" %14lf bytes/sec\n", x);                \
 102                else if (x < K * K)                                     \
 103                        printf(" %14lfd KB/sec\n", x / K);              \
 104                else if (x < K * K * K)                                 \
 105                        printf(" %14lf MB/sec\n", x / K / K);           \
 106                else                                                    \
 107                        printf(" %14lf GB/sec\n", x / K / K / K);       \
 108        } while (0)
 109
 110struct bench_mem_info {
 111        const struct function *functions;
 112        u64 (*do_cycles)(const struct function *r, size_t size, void *src, void *dst);
 113        double (*do_gettimeofday)(const struct function *r, size_t size, void *src, void *dst);
 114        const char *const *usage;
 115        bool alloc_src;
 116};
 117
 118static void __bench_mem_function(struct bench_mem_info *info, int r_idx, size_t size, double size_total)
 119{
 120        const struct function *r = &info->functions[r_idx];
 121        double result_bps = 0.0;
 122        u64 result_cycles = 0;
 123        void *src = NULL, *dst = zalloc(size);
 124
 125        printf("# function '%s' (%s)\n", r->name, r->desc);
 126
 127        if (dst == NULL)
 128                goto out_alloc_failed;
 129
 130        if (info->alloc_src) {
 131                src = zalloc(size);
 132                if (src == NULL)
 133                        goto out_alloc_failed;
 134        }
 135
 136        if (bench_format == BENCH_FORMAT_DEFAULT)
 137                printf("# Copying %s bytes ...\n\n", size_str);
 138
 139        if (use_cycles) {
 140                result_cycles = info->do_cycles(r, size, src, dst);
 141        } else {
 142                result_bps = info->do_gettimeofday(r, size, src, dst);
 143        }
 144
 145        switch (bench_format) {
 146        case BENCH_FORMAT_DEFAULT:
 147                if (use_cycles) {
 148                        printf(" %14lf cycles/byte\n", (double)result_cycles/size_total);
 149                } else {
 150                        print_bps(result_bps);
 151                }
 152                break;
 153
 154        case BENCH_FORMAT_SIMPLE:
 155                if (use_cycles) {
 156                        printf("%lf\n", (double)result_cycles/size_total);
 157                } else {
 158                        printf("%lf\n", result_bps);
 159                }
 160                break;
 161
 162        default:
 163                BUG_ON(1);
 164                break;
 165        }
 166
 167out_free:
 168        free(src);
 169        free(dst);
 170        return;
 171out_alloc_failed:
 172        printf("# Memory allocation failed - maybe size (%s) is too large?\n", size_str);
 173        goto out_free;
 174}
 175
 176static int bench_mem_common(int argc, const char **argv, struct bench_mem_info *info)
 177{
 178        int i;
 179        size_t size;
 180        double size_total;
 181
 182        argc = parse_options(argc, argv, options, info->usage, 0);
 183
 184        if (use_cycles) {
 185                i = init_cycles();
 186                if (i < 0) {
 187                        fprintf(stderr, "Failed to open cycles counter\n");
 188                        return i;
 189                }
 190        }
 191
 192        size = (size_t)perf_atoll((char *)size_str);
 193        size_total = (double)size * nr_loops;
 194
 195        if ((s64)size <= 0) {
 196                fprintf(stderr, "Invalid size:%s\n", size_str);
 197                return 1;
 198        }
 199
 200        if (!strncmp(function_str, "all", 3)) {
 201                for (i = 0; info->functions[i].name; i++)
 202                        __bench_mem_function(info, i, size, size_total);
 203                return 0;
 204        }
 205
 206        for (i = 0; info->functions[i].name; i++) {
 207                if (!strcmp(info->functions[i].name, function_str))
 208                        break;
 209        }
 210        if (!info->functions[i].name) {
 211                if (strcmp(function_str, "help") && strcmp(function_str, "h"))
 212                        printf("Unknown function: %s\n", function_str);
 213                printf("Available functions:\n");
 214                for (i = 0; info->functions[i].name; i++) {
 215                        printf("\t%s ... %s\n",
 216                               info->functions[i].name, info->functions[i].desc);
 217                }
 218                return 1;
 219        }
 220
 221        __bench_mem_function(info, i, size, size_total);
 222
 223        return 0;
 224}
 225
 226static void memcpy_prefault(memcpy_t fn, size_t size, void *src, void *dst)
 227{
 228        /* Make sure to always prefault zero pages even if MMAP_THRESH is crossed: */
 229        memset(src, 0, size);
 230
 231        /*
 232         * We prefault the freshly allocated memory range here,
 233         * to not measure page fault overhead:
 234         */
 235        fn(dst, src, size);
 236}
 237
 238static u64 do_memcpy_cycles(const struct function *r, size_t size, void *src, void *dst)
 239{
 240        u64 cycle_start = 0ULL, cycle_end = 0ULL;
 241        memcpy_t fn = r->fn.memcpy;
 242        int i;
 243
 244        memcpy_prefault(fn, size, src, dst);
 245
 246        cycle_start = get_cycles();
 247        for (i = 0; i < nr_loops; ++i)
 248                fn(dst, src, size);
 249        cycle_end = get_cycles();
 250
 251        return cycle_end - cycle_start;
 252}
 253
 254static double do_memcpy_gettimeofday(const struct function *r, size_t size, void *src, void *dst)
 255{
 256        struct timeval tv_start, tv_end, tv_diff;
 257        memcpy_t fn = r->fn.memcpy;
 258        int i;
 259
 260        memcpy_prefault(fn, size, src, dst);
 261
 262        BUG_ON(gettimeofday(&tv_start, NULL));
 263        for (i = 0; i < nr_loops; ++i)
 264                fn(dst, src, size);
 265        BUG_ON(gettimeofday(&tv_end, NULL));
 266
 267        timersub(&tv_end, &tv_start, &tv_diff);
 268
 269        return (double)(((double)size * nr_loops) / timeval2double(&tv_diff));
 270}
 271
 272struct function memcpy_functions[] = {
 273        { .name         = "default",
 274          .desc         = "Default memcpy() provided by glibc",
 275          .fn.memcpy    = memcpy },
 276
 277#ifdef HAVE_ARCH_X86_64_SUPPORT
 278# define MEMCPY_FN(_fn, _name, _desc) {.name = _name, .desc = _desc, .fn.memcpy = _fn},
 279# include "mem-memcpy-x86-64-asm-def.h"
 280# undef MEMCPY_FN
 281#endif
 282
 283        { .name = NULL, }
 284};
 285
 286static const char * const bench_mem_memcpy_usage[] = {
 287        "perf bench mem memcpy <options>",
 288        NULL
 289};
 290
 291int bench_mem_memcpy(int argc, const char **argv)
 292{
 293        struct bench_mem_info info = {
 294                .functions              = memcpy_functions,
 295                .do_cycles              = do_memcpy_cycles,
 296                .do_gettimeofday        = do_memcpy_gettimeofday,
 297                .usage                  = bench_mem_memcpy_usage,
 298                .alloc_src              = true,
 299        };
 300
 301        return bench_mem_common(argc, argv, &info);
 302}
 303
 304static u64 do_memset_cycles(const struct function *r, size_t size, void *src __maybe_unused, void *dst)
 305{
 306        u64 cycle_start = 0ULL, cycle_end = 0ULL;
 307        memset_t fn = r->fn.memset;
 308        int i;
 309
 310        /*
 311         * We prefault the freshly allocated memory range here,
 312         * to not measure page fault overhead:
 313         */
 314        fn(dst, -1, size);
 315
 316        cycle_start = get_cycles();
 317        for (i = 0; i < nr_loops; ++i)
 318                fn(dst, i, size);
 319        cycle_end = get_cycles();
 320
 321        return cycle_end - cycle_start;
 322}
 323
 324static double do_memset_gettimeofday(const struct function *r, size_t size, void *src __maybe_unused, void *dst)
 325{
 326        struct timeval tv_start, tv_end, tv_diff;
 327        memset_t fn = r->fn.memset;
 328        int i;
 329
 330        /*
 331         * We prefault the freshly allocated memory range here,
 332         * to not measure page fault overhead:
 333         */
 334        fn(dst, -1, size);
 335
 336        BUG_ON(gettimeofday(&tv_start, NULL));
 337        for (i = 0; i < nr_loops; ++i)
 338                fn(dst, i, size);
 339        BUG_ON(gettimeofday(&tv_end, NULL));
 340
 341        timersub(&tv_end, &tv_start, &tv_diff);
 342
 343        return (double)(((double)size * nr_loops) / timeval2double(&tv_diff));
 344}
 345
 346static const char * const bench_mem_memset_usage[] = {
 347        "perf bench mem memset <options>",
 348        NULL
 349};
 350
 351static const struct function memset_functions[] = {
 352        { .name         = "default",
 353          .desc         = "Default memset() provided by glibc",
 354          .fn.memset    = memset },
 355
 356#ifdef HAVE_ARCH_X86_64_SUPPORT
 357# define MEMSET_FN(_fn, _name, _desc) { .name = _name, .desc = _desc, .fn.memset = _fn },
 358# include "mem-memset-x86-64-asm-def.h"
 359# undef MEMSET_FN
 360#endif
 361
 362        { .name = NULL, }
 363};
 364
 365int bench_mem_memset(int argc, const char **argv)
 366{
 367        struct bench_mem_info info = {
 368                .functions              = memset_functions,
 369                .do_cycles              = do_memset_cycles,
 370                .do_gettimeofday        = do_memset_gettimeofday,
 371                .usage                  = bench_mem_memset_usage,
 372        };
 373
 374        return bench_mem_common(argc, argv, &info);
 375}
 376