nsprpub/pr/tests/switch.c

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /*
   7 ** File:            switch.c
   8 ** Description:     trying to time context switches
   9 */
  10
  11 #include "prinit.h"
  12 #include "prcvar.h"
  13 #include "prmem.h"
  14 #include "prinrval.h"
  15 #include "prlock.h"
  16 #include "prlog.h"
  17 #include "prthread.h"
  18 #include "prprf.h"
  19
  20 #include "plerror.h"
  21 #include "plgetopt.h"
  22
  23 #include "private/pprio.h"
  24
  25 #include <stdlib.h>
  26
  27 #define INNER_LOOPS 100
  28 #define DEFAULT_LOOPS 100
  29 #define DEFAULT_THREADS 10
  30
  31 static PRFileDesc *debug_out = NULL;
  32 static PRBool debug_mode = PR_FALSE, verbosity = PR_FALSE, failed = PR_FALSE;
  33
  34 typedef struct Shared
  35 {
  36     PRLock *ml;
  37     PRCondVar *cv;
  38     PRBool twiddle;
  39     PRThread *thread;
  40     struct Shared *next;
  41 } Shared;
  42
  43 static void Help(void)
  44 {
  45     debug_out = PR_STDOUT;
  46
  47     PR_fprintf(
  48         debug_out, "Usage: >./switch [-c n] [-t n] [-d] [-v] [-G] [-C n]\n");
  49     PR_fprintf(
  50         debug_out, "-c n\tloops at thread level (default: %d)\n", DEFAULT_LOOPS);
  51     PR_fprintf(
  52         debug_out, "-t n\tnumber of threads (default: %d)\n", DEFAULT_THREADS);
  53     PR_fprintf(debug_out, "-d\tturn on debugging output (default: FALSE)\n");
  54     PR_fprintf(debug_out, "-v\tturn on verbose output (default: FALSE)\n");
  55     PR_fprintf(debug_out, "-G\tglobal threads only (default: FALSE)\n");
  56     PR_fprintf(debug_out, "-C n\tconcurrency setting (default: 1)\n");
  57 }  /* Help */
  58
  59 static void PR_CALLBACK Notified(void *arg)
  60 {
  61     Shared *shared = (Shared*)arg;
  62     PRStatus status = PR_SUCCESS;
  63     while (PR_SUCCESS == status)
  64     {
  65         PR_Lock(shared->ml);
  66         while (shared->twiddle && (PR_SUCCESS == status)) {
  67             status = PR_WaitCondVar(shared->cv, PR_INTERVAL_NO_TIMEOUT);
  68         }
  69         if (verbosity) {
  70             PR_fprintf(debug_out, "+");
  71         }
  72         shared->twiddle = PR_TRUE;
  73         shared->next->twiddle = PR_FALSE;
  74         PR_NotifyCondVar(shared->next->cv);
  75         PR_Unlock(shared->ml);
  76     }
  77 }  /* Notified */
  78
  79 static Shared home;
  80 PRIntn PR_CALLBACK Switch(PRIntn argc, char **argv)
  81 {
  82     PLOptStatus os;
  83     PRStatus status;
  84     PRBool help = PR_FALSE;
  85     PRUintn concurrency = 1;
  86     Shared *shared, *link;
  87     PRIntervalTime timein, timeout;
  88     PRThreadScope thread_scope = PR_LOCAL_THREAD;
  89     PRUintn thread_count, inner_count, loop_count, average;
  90     PRUintn thread_limit = DEFAULT_THREADS, loop_limit = DEFAULT_LOOPS;
  91     PLOptState *opt = PL_CreateOptState(argc, argv, "hdvc:t:C:G");
  92     while (PL_OPT_EOL != (os = PL_GetNextOpt(opt)))
  93     {
  94         if (PL_OPT_BAD == os) {
  95             continue;
  96         }
  97         switch (opt->option)
  98         {
  99             case 'v':  /* verbose mode */
 100                 verbosity = PR_TRUE;
 101             case 'd':  /* debug mode */
 102                 debug_mode = PR_TRUE;
 103                 break;
 104             case 'c':  /* loop counter */
 105                 loop_limit = atoi(opt->value);
 106                 break;
 107             case 't':  /* thread limit */
 108                 thread_limit = atoi(opt->value);
 109                 break;
 110             case 'C':  /* Concurrency limit */
 111                 concurrency = atoi(opt->value);
 112                 break;
 113             case 'G':  /* global threads only */
 114                 thread_scope = PR_GLOBAL_THREAD;
 115                 break;
 116             case 'h':  /* help message */
 117                 Help();
 118                 help = PR_TRUE;
 119                 break;
 120             default:
 121                 break;
 122         }
 123     }
 124     PL_DestroyOptState(opt);
 125
 126     if (help) {
 127         return -1;
 128     }
 129
 130     if (PR_TRUE == debug_mode)
 131     {
 132         debug_out = PR_STDOUT;
 133         PR_fprintf(debug_out, "Test parameters\n");
 134         PR_fprintf(debug_out, "\tThreads involved: %d\n", thread_limit);
 135         PR_fprintf(debug_out, "\tIteration limit: %d\n", loop_limit);
 136         PR_fprintf(debug_out, "\tConcurrency: %d\n", concurrency);
 137         PR_fprintf(
 138             debug_out, "\tThread type: %s\n",
 139             (PR_GLOBAL_THREAD == thread_scope) ? "GLOBAL" : "LOCAL");
 140     }
 141
 142     PR_SetConcurrency(concurrency);
 143
 144     link = &home;
 145     home.ml = PR_NewLock();
 146     home.cv = PR_NewCondVar(home.ml);
 147     home.twiddle = PR_FALSE;
 148     home.next = NULL;
 149
 150     timeout = 0;
 151
 152     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 153     {
 154         shared = PR_NEWZAP(Shared);
 155
 156         shared->ml = home.ml;
 157         shared->cv = PR_NewCondVar(home.ml);
 158         shared->twiddle = PR_TRUE;
 159         shared->next = link;
 160         link = shared;
 161
 162         shared->thread = PR_CreateThread(
 163                              PR_USER_THREAD, Notified, shared,
 164                              PR_PRIORITY_HIGH, thread_scope,
 165                              PR_JOINABLE_THREAD, 0);
 166         PR_ASSERT(shared->thread != NULL);
 167         if (NULL == shared->thread) {
 168             failed = PR_TRUE;
 169         }
 170     }
 171
 172     for (loop_count = 1; loop_count <= loop_limit; ++loop_count)
 173     {
 174         timein = PR_IntervalNow();
 175         for (inner_count = 0; inner_count < INNER_LOOPS; ++inner_count)
 176         {
 177             PR_Lock(home.ml);
 178             home.twiddle = PR_TRUE;
 179             shared->twiddle = PR_FALSE;
 180             PR_NotifyCondVar(shared->cv);
 181             while (home.twiddle)
 182             {
 183                 status = PR_WaitCondVar(home.cv, PR_INTERVAL_NO_TIMEOUT);
 184                 if (PR_FAILURE == status) {
 185                     failed = PR_TRUE;
 186                 }
 187             }
 188             PR_Unlock(home.ml);
 189         }
 190         timeout += (PR_IntervalNow() - timein);
 191     }
 192
 193     if (debug_mode)
 194     {
 195         average = PR_IntervalToMicroseconds(timeout)
 196                   / (INNER_LOOPS * loop_limit * thread_count);
 197         PR_fprintf(
 198             debug_out, "Average switch times %d usecs for %d threads\n",
 199             average, thread_limit);
 200     }
 201
 202     link = shared;
 203     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 204     {
 205         if (&home == link) {
 206             break;
 207         }
 208         status = PR_Interrupt(link->thread);
 209         if (PR_SUCCESS != status)
 210         {
 211             failed = PR_TRUE;
 212             if (debug_mode) {
 213                 PL_FPrintError(debug_out, "Failed to interrupt");
 214             }
 215         }
 216         link = link->next;
 217     }
 218
 219     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 220     {
 221         link = shared->next;
 222         status = PR_JoinThread(shared->thread);
 223         if (PR_SUCCESS != status)
 224         {
 225             failed = PR_TRUE;
 226             if (debug_mode) {
 227                 PL_FPrintError(debug_out, "Failed to join");
 228             }
 229         }
 230         PR_DestroyCondVar(shared->cv);
 231         PR_DELETE(shared);
 232         if (&home == link) {
 233             break;
 234         }
 235         shared = link;
 236     }
 237     PR_DestroyCondVar(home.cv);
 238     PR_DestroyLock(home.ml);
 239
 240     PR_fprintf(PR_STDOUT, ((failed) ? "FAILED\n" : "PASSED\n"));
 241     return ((failed) ? 1 : 0);
 242 }  /* Switch */
 243
 244 int main(int argc, char **argv)
 245 {
 246     PRIntn result;
 247     PR_STDIO_INIT();
 248     result = PR_Initialize(Switch, argc, argv, 0);
 249     return result;
 250 }  /* main */
 251
 252 /* switch.c */