Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
sched-messaging.c
Go to the documentation of this file.
1 /*
2  *
3  * sched-messaging.c
4  *
5  * messaging: Benchmark for scheduler and IPC mechanisms
6  *
7  * Based on hackbench by Rusty Russell <[email protected]>
8  * Ported to perf by Hitoshi Mitake <[email protected]>
9  *
10  */
11 
12 #include "../perf.h"
13 #include "../util/util.h"
14 #include "../util/parse-options.h"
15 #include "../builtin.h"
16 #include "bench.h"
17 
18 /* Test groups of 20 processes spraying to 20 receivers */
19 #include <pthread.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <errno.h>
24 #include <unistd.h>
25 #include <sys/types.h>
26 #include <sys/socket.h>
27 #include <sys/wait.h>
28 #include <sys/time.h>
29 #include <sys/poll.h>
30 #include <limits.h>
31 
32 #define DATASIZE 100
33 
34 static bool use_pipes = false;
35 static unsigned int loops = 100;
36 static bool thread_mode = false;
37 static unsigned int num_groups = 10;
38 
40  unsigned int num_fds;
41  int ready_out;
42  int wakefd;
43  int out_fds[0];
44 };
45 
47  unsigned int num_packets;
48  int in_fds[2];
49  int ready_out;
50  int wakefd;
51 };
52 
53 static void barf(const char *msg)
54 {
55  fprintf(stderr, "%s (error: %s)\n", msg, strerror(errno));
56  exit(1);
57 }
58 
59 static void fdpair(int fds[2])
60 {
61  if (use_pipes) {
62  if (pipe(fds) == 0)
63  return;
64  } else {
65  if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0)
66  return;
67  }
68 
69  barf(use_pipes ? "pipe()" : "socketpair()");
70 }
71 
72 /* Block until we're ready to go */
73 static void ready(int ready_out, int wakefd)
74 {
75  char dummy;
76  struct pollfd pollfd = { .fd = wakefd, .events = POLLIN };
77 
78  /* Tell them we're ready. */
79  if (write(ready_out, &dummy, 1) != 1)
80  barf("CLIENT: ready write");
81 
82  /* Wait for "GO" signal */
83  if (poll(&pollfd, 1, -1) != 1)
84  barf("poll");
85 }
86 
87 /* Sender sprays loops messages down each file descriptor */
88 static void *sender(struct sender_context *ctx)
89 {
90  char data[DATASIZE];
91  unsigned int i, j;
92 
93  ready(ctx->ready_out, ctx->wakefd);
94 
95  /* Now pump to every receiver. */
96  for (i = 0; i < loops; i++) {
97  for (j = 0; j < ctx->num_fds; j++) {
98  int ret, done = 0;
99 
100 again:
101  ret = write(ctx->out_fds[j], data + done,
102  sizeof(data)-done);
103  if (ret < 0)
104  barf("SENDER: write");
105  done += ret;
106  if (done < DATASIZE)
107  goto again;
108  }
109  }
110 
111  return NULL;
112 }
113 
114 
115 /* One receiver per fd */
116 static void *receiver(struct receiver_context* ctx)
117 {
118  unsigned int i;
119 
120  if (!thread_mode)
121  close(ctx->in_fds[1]);
122 
123  /* Wait for start... */
124  ready(ctx->ready_out, ctx->wakefd);
125 
126  /* Receive them all */
127  for (i = 0; i < ctx->num_packets; i++) {
128  char data[DATASIZE];
129  int ret, done = 0;
130 
131 again:
132  ret = read(ctx->in_fds[0], data + done, DATASIZE - done);
133  if (ret < 0)
134  barf("SERVER: read");
135  done += ret;
136  if (done < DATASIZE)
137  goto again;
138  }
139 
140  return NULL;
141 }
142 
143 static pthread_t create_worker(void *ctx, void *(*func)(void *))
144 {
145  pthread_attr_t attr;
146  pthread_t childid;
147  int err;
148 
149  if (!thread_mode) {
150  /* process mode */
151  /* Fork the receiver. */
152  switch (fork()) {
153  case -1:
154  barf("fork()");
155  break;
156  case 0:
157  (*func) (ctx);
158  exit(0);
159  break;
160  default:
161  break;
162  }
163 
164  return (pthread_t)0;
165  }
166 
167  if (pthread_attr_init(&attr) != 0)
168  barf("pthread_attr_init:");
169 
170 #ifndef __ia64__
171  if (pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN) != 0)
172  barf("pthread_attr_setstacksize");
173 #endif
174 
175  err = pthread_create(&childid, &attr, func, ctx);
176  if (err != 0) {
177  fprintf(stderr, "pthread_create failed: %s (%d)\n",
178  strerror(err), err);
179  exit(-1);
180  }
181  return childid;
182 }
183 
184 static void reap_worker(pthread_t id)
185 {
186  int proc_status;
187  void *thread_status;
188 
189  if (!thread_mode) {
190  /* process mode */
191  wait(&proc_status);
192  if (!WIFEXITED(proc_status))
193  exit(1);
194  } else {
195  pthread_join(id, &thread_status);
196  }
197 }
198 
199 /* One group of senders and receivers */
200 static unsigned int group(pthread_t *pth,
201  unsigned int num_fds,
202  int ready_out,
203  int wakefd)
204 {
205  unsigned int i;
206  struct sender_context *snd_ctx = malloc(sizeof(struct sender_context)
207  + num_fds * sizeof(int));
208 
209  if (!snd_ctx)
210  barf("malloc()");
211 
212  for (i = 0; i < num_fds; i++) {
213  int fds[2];
214  struct receiver_context *ctx = malloc(sizeof(*ctx));
215 
216  if (!ctx)
217  barf("malloc()");
218 
219 
220  /* Create the pipe between client and server */
221  fdpair(fds);
222 
223  ctx->num_packets = num_fds * loops;
224  ctx->in_fds[0] = fds[0];
225  ctx->in_fds[1] = fds[1];
226  ctx->ready_out = ready_out;
227  ctx->wakefd = wakefd;
228 
229  pth[i] = create_worker(ctx, (void *)receiver);
230 
231  snd_ctx->out_fds[i] = fds[1];
232  if (!thread_mode)
233  close(fds[0]);
234  }
235 
236  /* Now we have all the fds, fork the senders */
237  for (i = 0; i < num_fds; i++) {
238  snd_ctx->ready_out = ready_out;
239  snd_ctx->wakefd = wakefd;
240  snd_ctx->num_fds = num_fds;
241 
242  pth[num_fds+i] = create_worker(snd_ctx, (void *)sender);
243  }
244 
245  /* Close the fds we have left */
246  if (!thread_mode)
247  for (i = 0; i < num_fds; i++)
248  close(snd_ctx->out_fds[i]);
249 
250  /* Return number of children to reap */
251  return num_fds * 2;
252 }
253 
254 static const struct option options[] = {
255  OPT_BOOLEAN('p', "pipe", &use_pipes,
256  "Use pipe() instead of socketpair()"),
257  OPT_BOOLEAN('t', "thread", &thread_mode,
258  "Be multi thread instead of multi process"),
259  OPT_UINTEGER('g', "group", &num_groups, "Specify number of groups"),
260  OPT_UINTEGER('l', "loop", &loops, "Specify number of loops"),
261  OPT_END()
262 };
263 
264 static const char * const bench_sched_message_usage[] = {
265  "perf bench sched messaging <options>",
266  NULL
267 };
268 
269 int bench_sched_messaging(int argc, const char **argv,
270  const char *prefix __maybe_unused)
271 {
272  unsigned int i, total_children;
273  struct timeval start, stop, diff;
274  unsigned int num_fds = 20;
275  int readyfds[2], wakefds[2];
276  char dummy;
277  pthread_t *pth_tab;
278 
279  argc = parse_options(argc, argv, options,
280  bench_sched_message_usage, 0);
281 
282  pth_tab = malloc(num_fds * 2 * num_groups * sizeof(pthread_t));
283  if (!pth_tab)
284  barf("main:malloc()");
285 
286  fdpair(readyfds);
287  fdpair(wakefds);
288 
289  total_children = 0;
290  for (i = 0; i < num_groups; i++)
291  total_children += group(pth_tab+total_children, num_fds,
292  readyfds[1], wakefds[0]);
293 
294  /* Wait for everyone to be ready */
295  for (i = 0; i < total_children; i++)
296  if (read(readyfds[0], &dummy, 1) != 1)
297  barf("Reading for readyfds");
298 
299  gettimeofday(&start, NULL);
300 
301  /* Kick them off */
302  if (write(wakefds[1], &dummy, 1) != 1)
303  barf("Writing to start them");
304 
305  /* Reap them all */
306  for (i = 0; i < total_children; i++)
307  reap_worker(pth_tab[i]);
308 
309  gettimeofday(&stop, NULL);
310 
311  timersub(&stop, &start, &diff);
312 
313  switch (bench_format) {
315  printf("# %d sender and receiver %s per group\n",
316  num_fds, thread_mode ? "threads" : "processes");
317  printf("# %d groups == %d %s run\n\n",
318  num_groups, num_groups * 2 * num_fds,
319  thread_mode ? "threads" : "processes");
320  printf(" %14s: %lu.%03lu [sec]\n", "Total time",
321  diff.tv_sec,
322  (unsigned long) (diff.tv_usec/1000));
323  break;
324  case BENCH_FORMAT_SIMPLE:
325  printf("%lu.%03lu\n", diff.tv_sec,
326  (unsigned long) (diff.tv_usec/1000));
327  break;
328  default:
329  /* reaching here is something disaster */
330  fprintf(stderr, "Unknown format:%d\n", bench_format);
331  exit(1);
332  break;
333  }
334 
335  return 0;
336 }