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mem-memcpy.c
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1 /*
2  * mem-memcpy.c
3  *
4  * memcpy: Simple memory copy in various ways
5  *
6  * Written by Hitoshi Mitake <[email protected]>
7  */
8 
9 #include "../perf.h"
10 #include "../util/util.h"
11 #include "../util/parse-options.h"
12 #include "../util/header.h"
13 #include "bench.h"
14 #include "mem-memcpy-arch.h"
15 
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <sys/time.h>
20 #include <errno.h>
21 
22 #define K 1024
23 
24 static const char *length_str = "1MB";
25 static const char *routine = "default";
26 static int iterations = 1;
27 static bool use_cycle;
28 static int cycle_fd;
29 static bool only_prefault;
30 static bool no_prefault;
31 
32 static const struct option options[] = {
33  OPT_STRING('l', "length", &length_str, "1MB",
34  "Specify length of memory to copy. "
35  "Available units: B, KB, MB, GB and TB (upper and lower)"),
36  OPT_STRING('r', "routine", &routine, "default",
37  "Specify routine to copy"),
38  OPT_INTEGER('i', "iterations", &iterations,
39  "repeat memcpy() invocation this number of times"),
40  OPT_BOOLEAN('c', "cycle", &use_cycle,
41  "Use cycles event instead of gettimeofday() for measuring"),
42  OPT_BOOLEAN('o', "only-prefault", &only_prefault,
43  "Show only the result with page faults before memcpy()"),
44  OPT_BOOLEAN('n', "no-prefault", &no_prefault,
45  "Show only the result without page faults before memcpy()"),
46  OPT_END()
47 };
48 
49 typedef void *(*memcpy_t)(void *, const void *, size_t);
50 
51 struct routine {
52  const char *name;
53  const char *desc;
55 };
56 
57 struct routine routines[] = {
58  { "default",
59  "Default memcpy() provided by glibc",
60  memcpy },
61 #ifdef ARCH_X86_64
62 
63 #define MEMCPY_FN(fn, name, desc) { name, desc, fn },
65 #undef MEMCPY_FN
66 
67 #endif
68 
69  { NULL,
70  NULL,
71  NULL }
72 };
73 
74 static const char * const bench_mem_memcpy_usage[] = {
75  "perf bench mem memcpy <options>",
76  NULL
77 };
78 
79 static struct perf_event_attr cycle_attr = {
80  .type = PERF_TYPE_HARDWARE,
81  .config = PERF_COUNT_HW_CPU_CYCLES
82 };
83 
84 static void init_cycle(void)
85 {
86  cycle_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1, 0);
87 
88  if (cycle_fd < 0 && errno == ENOSYS)
89  die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
90  else
91  BUG_ON(cycle_fd < 0);
92 }
93 
94 static u64 get_cycle(void)
95 {
96  int ret;
97  u64 clk;
98 
99  ret = read(cycle_fd, &clk, sizeof(u64));
100  BUG_ON(ret != sizeof(u64));
101 
102  return clk;
103 }
104 
105 static double timeval2double(struct timeval *ts)
106 {
107  return (double)ts->tv_sec +
108  (double)ts->tv_usec / (double)1000000;
109 }
110 
111 static void alloc_mem(void **dst, void **src, size_t length)
112 {
113  *dst = zalloc(length);
114  if (!dst)
115  die("memory allocation failed - maybe length is too large?\n");
116 
117  *src = zalloc(length);
118  if (!src)
119  die("memory allocation failed - maybe length is too large?\n");
120 }
121 
122 static u64 do_memcpy_cycle(memcpy_t fn, size_t len, bool prefault)
123 {
124  u64 cycle_start = 0ULL, cycle_end = 0ULL;
125  void *src = NULL, *dst = NULL;
126  int i;
127 
128  alloc_mem(&src, &dst, len);
129 
130  if (prefault)
131  fn(dst, src, len);
132 
133  cycle_start = get_cycle();
134  for (i = 0; i < iterations; ++i)
135  fn(dst, src, len);
136  cycle_end = get_cycle();
137 
138  free(src);
139  free(dst);
140  return cycle_end - cycle_start;
141 }
142 
143 static double do_memcpy_gettimeofday(memcpy_t fn, size_t len, bool prefault)
144 {
145  struct timeval tv_start, tv_end, tv_diff;
146  void *src = NULL, *dst = NULL;
147  int i;
148 
149  alloc_mem(&src, &dst, len);
150 
151  if (prefault)
152  fn(dst, src, len);
153 
154  BUG_ON(gettimeofday(&tv_start, NULL));
155  for (i = 0; i < iterations; ++i)
156  fn(dst, src, len);
157  BUG_ON(gettimeofday(&tv_end, NULL));
158 
159  timersub(&tv_end, &tv_start, &tv_diff);
160 
161  free(src);
162  free(dst);
163  return (double)((double)len / timeval2double(&tv_diff));
164 }
165 
166 #define pf (no_prefault ? 0 : 1)
167 
168 #define print_bps(x) do { \
169  if (x < K) \
170  printf(" %14lf B/Sec", x); \
171  else if (x < K * K) \
172  printf(" %14lfd KB/Sec", x / K); \
173  else if (x < K * K * K) \
174  printf(" %14lf MB/Sec", x / K / K); \
175  else \
176  printf(" %14lf GB/Sec", x / K / K / K); \
177  } while (0)
178 
179 int bench_mem_memcpy(int argc, const char **argv,
180  const char *prefix __maybe_unused)
181 {
182  int i;
183  size_t len;
184  double result_bps[2];
185  u64 result_cycle[2];
186 
187  argc = parse_options(argc, argv, options,
188  bench_mem_memcpy_usage, 0);
189 
190  if (use_cycle)
191  init_cycle();
192 
193  len = (size_t)perf_atoll((char *)length_str);
194 
195  result_cycle[0] = result_cycle[1] = 0ULL;
196  result_bps[0] = result_bps[1] = 0.0;
197 
198  if ((s64)len <= 0) {
199  fprintf(stderr, "Invalid length:%s\n", length_str);
200  return 1;
201  }
202 
203  /* same to without specifying either of prefault and no-prefault */
204  if (only_prefault && no_prefault)
205  only_prefault = no_prefault = false;
206 
207  for (i = 0; routines[i].name; i++) {
208  if (!strcmp(routines[i].name, routine))
209  break;
210  }
211  if (!routines[i].name) {
212  printf("Unknown routine:%s\n", routine);
213  printf("Available routines...\n");
214  for (i = 0; routines[i].name; i++) {
215  printf("\t%s ... %s\n",
216  routines[i].name, routines[i].desc);
217  }
218  return 1;
219  }
220 
222  printf("# Copying %s Bytes ...\n\n", length_str);
223 
224  if (!only_prefault && !no_prefault) {
225  /* show both of results */
226  if (use_cycle) {
227  result_cycle[0] =
228  do_memcpy_cycle(routines[i].fn, len, false);
229  result_cycle[1] =
230  do_memcpy_cycle(routines[i].fn, len, true);
231  } else {
232  result_bps[0] =
233  do_memcpy_gettimeofday(routines[i].fn,
234  len, false);
235  result_bps[1] =
236  do_memcpy_gettimeofday(routines[i].fn,
237  len, true);
238  }
239  } else {
240  if (use_cycle) {
241  result_cycle[pf] =
242  do_memcpy_cycle(routines[i].fn,
243  len, only_prefault);
244  } else {
245  result_bps[pf] =
246  do_memcpy_gettimeofday(routines[i].fn,
247  len, only_prefault);
248  }
249  }
250 
251  switch (bench_format) {
253  if (!only_prefault && !no_prefault) {
254  if (use_cycle) {
255  printf(" %14lf Cycle/Byte\n",
256  (double)result_cycle[0]
257  / (double)len);
258  printf(" %14lf Cycle/Byte (with prefault)\n",
259  (double)result_cycle[1]
260  / (double)len);
261  } else {
262  print_bps(result_bps[0]);
263  printf("\n");
264  print_bps(result_bps[1]);
265  printf(" (with prefault)\n");
266  }
267  } else {
268  if (use_cycle) {
269  printf(" %14lf Cycle/Byte",
270  (double)result_cycle[pf]
271  / (double)len);
272  } else
273  print_bps(result_bps[pf]);
274 
275  printf("%s\n", only_prefault ? " (with prefault)" : "");
276  }
277  break;
278  case BENCH_FORMAT_SIMPLE:
279  if (!only_prefault && !no_prefault) {
280  if (use_cycle) {
281  printf("%lf %lf\n",
282  (double)result_cycle[0] / (double)len,
283  (double)result_cycle[1] / (double)len);
284  } else {
285  printf("%lf %lf\n",
286  result_bps[0], result_bps[1]);
287  }
288  } else {
289  if (use_cycle) {
290  printf("%lf\n", (double)result_cycle[pf]
291  / (double)len);
292  } else
293  printf("%lf\n", result_bps[pf]);
294  }
295  break;
296  default:
297  /* reaching this means there's some disaster: */
298  die("unknown format: %d\n", bench_format);
299  break;
300  }
301 
302  return 0;
303 }