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                 if (verbosity) PR_fprintf(debug_out, "+");
  69         shared->twiddle = PR_TRUE;
  70         shared->next->twiddle = PR_FALSE;
  71         PR_NotifyCondVar(shared->next->cv);
  72         PR_Unlock(shared->ml);
  73     }
  74 }  /* Notified */
  75
  76 static Shared home;
  77 PRIntn PR_CALLBACK Switch(PRIntn argc, char **argv)
  78 {
  79         PLOptStatus os;
  80     PRStatus status;
  81     PRBool help = PR_FALSE;
  82     PRUintn concurrency = 1;
  83     Shared *shared, *link;
  84     PRIntervalTime timein, timeout;
  85     PRThreadScope thread_scope = PR_LOCAL_THREAD;
  86     PRUintn thread_count, inner_count, loop_count, average;
  87     PRUintn thread_limit = DEFAULT_THREADS, loop_limit = DEFAULT_LOOPS;
  88         PLOptState *opt = PL_CreateOptState(argc, argv, "hdvc:t:C:G");
  89         while (PL_OPT_EOL != (os = PL_GetNextOpt(opt)))
  90     {
  91                 if (PL_OPT_BAD == os) continue;
  92         switch (opt->option)
  93         {
  94         case 'v':  /* verbose mode */
  95                         verbosity = PR_TRUE;
  96         case 'd':  /* debug mode */
  97                         debug_mode = PR_TRUE;
  98             break;
  99         case 'c':  /* loop counter */
 100                         loop_limit = atoi(opt->value);
 101             break;
 102         case 't':  /* thread limit */
 103                         thread_limit = atoi(opt->value);
 104             break;
 105         case 'C':  /* Concurrency limit */
 106                         concurrency = atoi(opt->value);
 107             break;
 108         case 'G':  /* global threads only */
 109                         thread_scope = PR_GLOBAL_THREAD;
 110             break;
 111         case 'h':  /* help message */
 112                         Help();
 113                         help = PR_TRUE;
 114             break;
 115          default:
 116             break;
 117         }
 118     }
 119         PL_DestroyOptState(opt);
 120
 121     if (help) return -1;
 122
 123         if (PR_TRUE == debug_mode)
 124         {
 125                 debug_out = PR_STDOUT;
 126                 PR_fprintf(debug_out, "Test parameters\n");
 127                 PR_fprintf(debug_out, "\tThreads involved: %d\n", thread_limit);
 128                 PR_fprintf(debug_out, "\tIteration limit: %d\n", loop_limit);
 129                 PR_fprintf(debug_out, "\tConcurrency: %d\n", concurrency);
 130                 PR_fprintf(
 131                         debug_out, "\tThread type: %s\n",
 132                         (PR_GLOBAL_THREAD == thread_scope) ? "GLOBAL" : "LOCAL");
 133         }
 134
 135     PR_SetConcurrency(concurrency);
 136
 137     link = &home;
 138     home.ml = PR_NewLock();
 139     home.cv = PR_NewCondVar(home.ml);
 140     home.twiddle = PR_FALSE;
 141     home.next = NULL;
 142
 143     timeout = 0;
 144
 145     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 146     {
 147         shared = PR_NEWZAP(Shared);
 148
 149         shared->ml = home.ml;
 150         shared->cv = PR_NewCondVar(home.ml);
 151         shared->twiddle = PR_TRUE;
 152         shared->next = link;
 153         link = shared;
 154
 155         shared->thread = PR_CreateThread(
 156             PR_USER_THREAD, Notified, shared,
 157             PR_PRIORITY_HIGH, thread_scope,
 158             PR_JOINABLE_THREAD, 0);
 159         PR_ASSERT(shared->thread != NULL);
 160         if (NULL == shared->thread)
 161             failed = PR_TRUE;
 162         }
 163
 164     for (loop_count = 1; loop_count <= loop_limit; ++loop_count)
 165     {
 166                 timein = PR_IntervalNow();
 167                 for (inner_count = 0; inner_count < INNER_LOOPS; ++inner_count)
 168                 {
 169                         PR_Lock(home.ml);
 170                         home.twiddle = PR_TRUE;
 171                         shared->twiddle = PR_FALSE;
 172                         PR_NotifyCondVar(shared->cv);
 173                         while (home.twiddle)
 174             {
 175                                 status = PR_WaitCondVar(home.cv, PR_INTERVAL_NO_TIMEOUT);
 176                                 if (PR_FAILURE == status)
 177                                     failed = PR_TRUE;
 178             }
 179                         PR_Unlock(home.ml);
 180                 }
 181                 timeout += (PR_IntervalNow() - timein);
 182         }
 183
 184         if (debug_mode)
 185         {
 186                 average = PR_IntervalToMicroseconds(timeout)
 187                         / (INNER_LOOPS * loop_limit * thread_count);
 188                 PR_fprintf(
 189                         debug_out, "Average switch times %d usecs for %d threads\n",
 190             average, thread_limit);
 191         }
 192
 193     link = shared;
 194     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 195     {
 196         if (&home == link) break;
 197         status = PR_Interrupt(link->thread);
 198                 if (PR_SUCCESS != status)
 199         {
 200             failed = PR_TRUE;
 201             if (debug_mode)
 202                             PL_FPrintError(debug_out, "Failed to interrupt");
 203         }
 204                 link = link->next;
 205     }
 206
 207     for (thread_count = 1; thread_count <= thread_limit; ++thread_count)
 208     {
 209         link = shared->next;
 210         status = PR_JoinThread(shared->thread);
 211                 if (PR_SUCCESS != status)
 212                 {
 213             failed = PR_TRUE;
 214             if (debug_mode)
 215                             PL_FPrintError(debug_out, "Failed to join");
 216         }
 217         PR_DestroyCondVar(shared->cv);
 218         PR_DELETE(shared);
 219         if (&home == link) break;
 220         shared = link;
 221     }
 222     PR_DestroyCondVar(home.cv);
 223     PR_DestroyLock(home.ml);
 224
 225     PR_fprintf(PR_STDOUT, ((failed) ? "FAILED\n" : "PASSED\n"));
 226     return ((failed) ? 1 : 0);
 227 }  /* Switch */
 228
 229 int main(int argc, char **argv)
 230 {
 231     PRIntn result;
 232     PR_STDIO_INIT();
 233     result = PR_Initialize(Switch, argc, argv, 0);
 234     return result;
 235 }  /* main */
 236
 237 /* switch.c */