root/tools/perf/bench/sched-messaging.c

DEFINITIONS

1. fdpair
2. ready
3. sender
4. receiver
5. create_worker
6. reap_worker
7. group
8. bench_sched_messaging

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *
   4  * sched-messaging.c
   5  *
   6  * messaging: Benchmark for scheduler and IPC mechanisms
   7  *
   8  * Based on hackbench by Rusty Russell <rusty@rustcorp.com.au>
   9  * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
  10  *
  11  */
  12 
  13 #include <subcmd/parse-options.h>
  14 #include "bench.h"
  15 
  16 /* Test groups of 20 processes spraying to 20 receivers */
  17 #include <pthread.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <errno.h>
  22 #include <unistd.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <sys/wait.h>
  26 #include <sys/time.h>
  27 #include <poll.h>
  28 #include <limits.h>
  29 #include <err.h>
  30 #include <linux/time64.h>
  31 
  32 #define DATASIZE 100
  33 
  34 static bool use_pipes = false;
  35 static unsigned int nr_loops = 100;
  36 static bool thread_mode = false;
  37 static unsigned int num_groups = 10;
  38 
  39 struct sender_context {
  40         unsigned int num_fds;
  41         int ready_out;
  42         int wakefd;
  43         int out_fds[0];
  44 };
  45 
  46 struct receiver_context {
  47         unsigned int num_packets;
  48         int in_fds[2];
  49         int ready_out;
  50         int wakefd;
  51 };
  52 
  53 static void fdpair(int fds[2])
  54 {
  55         if (use_pipes) {
  56                 if (pipe(fds) == 0)
  57                         return;
  58         } else {
  59                 if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0)
  60                         return;
  61         }
  62 
  63         err(EXIT_FAILURE, use_pipes ? "pipe()" : "socketpair()");
  64 }
  65 
  66 /* Block until we're ready to go */
  67 static void ready(int ready_out, int wakefd)
  68 {
  69         char dummy;
  70         struct pollfd pollfd = { .fd = wakefd, .events = POLLIN };
  71 
  72         /* Tell them we're ready. */
  73         if (write(ready_out, &dummy, 1) != 1)
  74                 err(EXIT_FAILURE, "CLIENT: ready write");
  75 
  76         /* Wait for "GO" signal */
  77         if (poll(&pollfd, 1, -1) != 1)
  78                 err(EXIT_FAILURE, "poll");
  79 }
  80 
  81 /* Sender sprays nr_loops messages down each file descriptor */
  82 static void *sender(struct sender_context *ctx)
  83 {
  84         char data[DATASIZE];
  85         unsigned int i, j;
  86 
  87         ready(ctx->ready_out, ctx->wakefd);
  88 
  89         /* Now pump to every receiver. */
  90         for (i = 0; i < nr_loops; i++) {
  91                 for (j = 0; j < ctx->num_fds; j++) {
  92                         int ret, done = 0;
  93 
  94 again:
  95                         ret = write(ctx->out_fds[j], data + done,
  96                                     sizeof(data)-done);
  97                         if (ret < 0)
  98                                 err(EXIT_FAILURE, "SENDER: write");
  99                         done += ret;
 100                         if (done < DATASIZE)
 101                                 goto again;
 102                 }
 103         }
 104 
 105         return NULL;
 106 }
 107 
 108 
 109 /* One receiver per fd */
 110 static void *receiver(struct receiver_context* ctx)
 111 {
 112         unsigned int i;
 113 
 114         if (!thread_mode)
 115                 close(ctx->in_fds[1]);
 116 
 117         /* Wait for start... */
 118         ready(ctx->ready_out, ctx->wakefd);
 119 
 120         /* Receive them all */
 121         for (i = 0; i < ctx->num_packets; i++) {
 122                 char data[DATASIZE];
 123                 int ret, done = 0;
 124 
 125 again:
 126                 ret = read(ctx->in_fds[0], data + done, DATASIZE - done);
 127                 if (ret < 0)
 128                         err(EXIT_FAILURE, "SERVER: read");
 129                 done += ret;
 130                 if (done < DATASIZE)
 131                         goto again;
 132         }
 133 
 134         return NULL;
 135 }
 136 
 137 static pthread_t create_worker(void *ctx, void *(*func)(void *))
 138 {
 139         pthread_attr_t attr;
 140         pthread_t childid;
 141         int ret;
 142 
 143         if (!thread_mode) {
 144                 /* process mode */
 145                 /* Fork the receiver. */
 146                 switch (fork()) {
 147                 case -1:
 148                         err(EXIT_FAILURE, "fork()");
 149                         break;
 150                 case 0:
 151                         (*func) (ctx);
 152                         exit(0);
 153                         break;
 154                 default:
 155                         break;
 156                 }
 157 
 158                 return (pthread_t)0;
 159         }
 160 
 161         if (pthread_attr_init(&attr) != 0)
 162                 err(EXIT_FAILURE, "pthread_attr_init:");
 163 
 164 #ifndef __ia64__
 165         if (pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN) != 0)
 166                 err(EXIT_FAILURE, "pthread_attr_setstacksize");
 167 #endif
 168 
 169         ret = pthread_create(&childid, &attr, func, ctx);
 170         if (ret != 0)
 171                 err(EXIT_FAILURE, "pthread_create failed");
 172 
 173         return childid;
 174 }
 175 
 176 static void reap_worker(pthread_t id)
 177 {
 178         int proc_status;
 179         void *thread_status;
 180 
 181         if (!thread_mode) {
 182                 /* process mode */
 183                 wait(&proc_status);
 184                 if (!WIFEXITED(proc_status))
 185                         exit(1);
 186         } else {
 187                 pthread_join(id, &thread_status);
 188         }
 189 }
 190 
 191 /* One group of senders and receivers */
 192 static unsigned int group(pthread_t *pth,
 193                 unsigned int num_fds,
 194                 int ready_out,
 195                 int wakefd)
 196 {
 197         unsigned int i;
 198         struct sender_context *snd_ctx = malloc(sizeof(struct sender_context)
 199                         + num_fds * sizeof(int));
 200 
 201         if (!snd_ctx)
 202                 err(EXIT_FAILURE, "malloc()");
 203 
 204         for (i = 0; i < num_fds; i++) {
 205                 int fds[2];
 206                 struct receiver_context *ctx = malloc(sizeof(*ctx));
 207 
 208                 if (!ctx)
 209                         err(EXIT_FAILURE, "malloc()");
 210 
 211 
 212                 /* Create the pipe between client and server */
 213                 fdpair(fds);
 214 
 215                 ctx->num_packets = num_fds * nr_loops;
 216                 ctx->in_fds[0] = fds[0];
 217                 ctx->in_fds[1] = fds[1];
 218                 ctx->ready_out = ready_out;
 219                 ctx->wakefd = wakefd;
 220 
 221                 pth[i] = create_worker(ctx, (void *)receiver);
 222 
 223                 snd_ctx->out_fds[i] = fds[1];
 224                 if (!thread_mode)
 225                         close(fds[0]);
 226         }
 227 
 228         /* Now we have all the fds, fork the senders */
 229         for (i = 0; i < num_fds; i++) {
 230                 snd_ctx->ready_out = ready_out;
 231                 snd_ctx->wakefd = wakefd;
 232                 snd_ctx->num_fds = num_fds;
 233 
 234                 pth[num_fds+i] = create_worker(snd_ctx, (void *)sender);
 235         }
 236 
 237         /* Close the fds we have left */
 238         if (!thread_mode)
 239                 for (i = 0; i < num_fds; i++)
 240                         close(snd_ctx->out_fds[i]);
 241 
 242         /* Return number of children to reap */
 243         return num_fds * 2;
 244 }
 245 
 246 static const struct option options[] = {
 247         OPT_BOOLEAN('p', "pipe", &use_pipes,
 248                     "Use pipe() instead of socketpair()"),
 249         OPT_BOOLEAN('t', "thread", &thread_mode,
 250                     "Be multi thread instead of multi process"),
 251         OPT_UINTEGER('g', "group", &num_groups, "Specify number of groups"),
 252         OPT_UINTEGER('l', "nr_loops", &nr_loops, "Specify the number of loops to run (default: 100)"),
 253         OPT_END()
 254 };
 255 
 256 static const char * const bench_sched_message_usage[] = {
 257         "perf bench sched messaging <options>",
 258         NULL
 259 };
 260 
 261 int bench_sched_messaging(int argc, const char **argv)
 262 {
 263         unsigned int i, total_children;
 264         struct timeval start, stop, diff;
 265         unsigned int num_fds = 20;
 266         int readyfds[2], wakefds[2];
 267         char dummy;
 268         pthread_t *pth_tab;
 269 
 270         argc = parse_options(argc, argv, options,
 271                              bench_sched_message_usage, 0);
 272 
 273         pth_tab = malloc(num_fds * 2 * num_groups * sizeof(pthread_t));
 274         if (!pth_tab)
 275                 err(EXIT_FAILURE, "main:malloc()");
 276 
 277         fdpair(readyfds);
 278         fdpair(wakefds);
 279 
 280         total_children = 0;
 281         for (i = 0; i < num_groups; i++)
 282                 total_children += group(pth_tab+total_children, num_fds,
 283                                         readyfds[1], wakefds[0]);
 284 
 285         /* Wait for everyone to be ready */
 286         for (i = 0; i < total_children; i++)
 287                 if (read(readyfds[0], &dummy, 1) != 1)
 288                         err(EXIT_FAILURE, "Reading for readyfds");
 289 
 290         gettimeofday(&start, NULL);
 291 
 292         /* Kick them off */
 293         if (write(wakefds[1], &dummy, 1) != 1)
 294                 err(EXIT_FAILURE, "Writing to start them");
 295 
 296         /* Reap them all */
 297         for (i = 0; i < total_children; i++)
 298                 reap_worker(pth_tab[i]);
 299 
 300         gettimeofday(&stop, NULL);
 301 
 302         timersub(&stop, &start, &diff);
 303 
 304         switch (bench_format) {
 305         case BENCH_FORMAT_DEFAULT:
 306                 printf("# %d sender and receiver %s per group\n",
 307                        num_fds, thread_mode ? "threads" : "processes");
 308                 printf("# %d groups == %d %s run\n\n",
 309                        num_groups, num_groups * 2 * num_fds,
 310                        thread_mode ? "threads" : "processes");
 311                 printf(" %14s: %lu.%03lu [sec]\n", "Total time",
 312                        diff.tv_sec,
 313                        (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
 314                 break;
 315         case BENCH_FORMAT_SIMPLE:
 316                 printf("%lu.%03lu\n", diff.tv_sec,
 317                        (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
 318                 break;
 319         default:
 320                 /* reaching here is something disaster */
 321                 fprintf(stderr, "Unknown format:%d\n", bench_format);
 322                 exit(1);
 323                 break;
 324         }
 325 
 326         free(pth_tab);
 327 
 328         return 0;
 329 }