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(attr: &cycle_attr, pid: getpid(), cpu: -1, group_fd: -1, flags: 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(str: (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, r_idx: 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, r_idx: 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(ts: &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: &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(ts: &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: &info);
375}
376

source code of linux/tools/perf/bench/mem-functions.c