tor-browser

lockfile.c (6939B)

---

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
** File:        lockfile.c
** Purpose:     test basic locking functions
**              Just because this times stuff, don't think its a perforamnce
**              test!!!
**
** Modification History:
** 19-May-97 AGarcia- Converted the test to accomodate the debug_mode flag.
**           The debug mode will print all of the printfs associated with this
*test.
**           The regress mode will be the default mode. Since the regress tool
*limits
**           the output to a one line status:PASS or FAIL,all of the printf
*statements
**           have been handled with an if (debug_mode) statement.
** 04-June-97 AGarcia removed the Test_Result function. Regress tool has been
*updated to
**          recognize the return code from tha main program.
***********************************************************************/
/***********************************************************************
** Includes
***********************************************************************/
/* Used to get the command line option */
#include "plgetopt.h"

#include "prcmon.h"
#include "prerror.h"
#include "prinit.h"
#include "prinrval.h"
#include "prlock.h"
#include "prlog.h"
#include "prmon.h"
#include "prthread.h"
#include "prtypes.h"

#include "private/pprio.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

PRIntn failed_already = 0;
PRIntn debug_mode;

const static PRIntervalTime contention_interval = 50;

typedef struct LockContentious_s {
 PRLock* ml;
 PRInt32 loops;
 PRIntervalTime overhead;
 PRIntervalTime interval;
} LockContentious_t;

#define LOCKFILE "prlock.fil"

static PRIntervalTime NonContentiousLock(PRInt32 loops) {
 PRFileDesc* _lockfile;
 while (loops-- > 0) {
   _lockfile = PR_Open(LOCKFILE, PR_CREATE_FILE | PR_RDWR, 0666);
   if (!_lockfile) {
     if (debug_mode)
       printf("could not create lockfile: %d [%d]\n", PR_GetError(),
              PR_GetOSError());
     return PR_INTERVAL_NO_TIMEOUT;
   }
   PR_LockFile(_lockfile);
   PR_UnlockFile(_lockfile);
   PR_Close(_lockfile);
 }
 return 0;
} /* NonContentiousLock */

static void PR_CALLBACK LockContender(void* arg) {
 LockContentious_t* contention = (LockContentious_t*)arg;
 PRFileDesc* _lockfile;
 while (contention->loops-- > 0) {
   _lockfile = PR_Open(LOCKFILE, PR_CREATE_FILE | PR_RDWR, 0666);
   if (!_lockfile) {
     if (debug_mode)
       printf("could not create lockfile: %d [%d]\n", PR_GetError(),
              PR_GetOSError());
     break;
   }
   PR_LockFile(_lockfile);
   PR_Sleep(contention->interval);
   PR_UnlockFile(_lockfile);
   PR_Close(_lockfile);
 }

} /* LockContender */

/*
** Win16 requires things passed to Threads not be on the stack
*/
static LockContentious_t contention;

static PRIntervalTime ContentiousLock(PRInt32 loops) {
 PRStatus status;
 PRThread* thread = NULL;
 PRIntervalTime overhead, timein = PR_IntervalNow();

 contention.loops = loops;
 contention.overhead = 0;
 contention.ml = PR_NewLock();
 contention.interval = contention_interval;
 thread =
     PR_CreateThread(PR_USER_THREAD, LockContender, &contention,
                     PR_PRIORITY_LOW, PR_LOCAL_THREAD, PR_JOINABLE_THREAD, 0);
 PR_ASSERT(thread != NULL);

 overhead = PR_IntervalNow() - timein;

 while (contention.loops > 0) {
   PR_Lock(contention.ml);
   contention.overhead += contention.interval;
   PR_Sleep(contention.interval);
   PR_Unlock(contention.ml);
 }

 timein = PR_IntervalNow();
 status = PR_JoinThread(thread);
 PR_DestroyLock(contention.ml);
 overhead += (PR_IntervalNow() - timein);
 return overhead + contention.overhead;
} /* ContentiousLock */

static PRIntervalTime Test(const char* msg,
                          PRIntervalTime (*test)(PRInt32 loops), PRInt32 loops,
                          PRIntervalTime overhead) {
 /*
  * overhead - overhead not measured by the test.
  * duration - wall clock time it took to perform test.
  * predicted - extra time test says should not be counted
  *
  * Time accountable to the test is duration - overhead - predicted
  * All times are Intervals and accumulated for all iterations.
  */
 PRFloat64 elapsed;
 PRIntervalTime accountable, duration;
 PRUintn spaces = strlen(msg);
 PRIntervalTime timeout, timein = PR_IntervalNow();
 PRIntervalTime predicted = test(loops);
 timeout = PR_IntervalNow();
 duration = timeout - timein;
 accountable = duration - predicted;
 accountable -= overhead;
 elapsed = (PRFloat64)PR_IntervalToMicroseconds(accountable);
 if (debug_mode) {
   printf("%s:", msg);
 }
 while (spaces++ < 50)
   if (debug_mode) {
     printf(" ");
   }
 if ((PRInt32)accountable < 0) {
   if (debug_mode) {
     printf("*****.** usecs/iteration\n");
   }
 } else {
   if (debug_mode) {
     printf("%8.2f usecs/iteration\n", elapsed / loops);
   }
 }
 return duration;
} /* Test */

int main(int argc, char** argv) {
 PRIntervalTime duration;
 PRUint32 cpu, cpus = 2;
 PRInt32 loops = 100;

 /* The command line argument: -d is used to determine if the test is being run
 in debug mode. The regress tool requires only one line output:PASS or FAIL.
 All of the printfs associated with this test has been handled with a if
 (debug_mode) test. Usage: test_name -d
 */
 PLOptStatus os;
 PLOptState* opt = PL_CreateOptState(argc, argv, "d:");
 while (PL_OPT_EOL != (os = PL_GetNextOpt(opt))) {
   if (PL_OPT_BAD == os) {
     continue;
   }
   switch (opt->option) {
     case 'd': /* debug mode */
       debug_mode = 1;
       break;
     default:
       break;
   }
 }
 PL_DestroyOptState(opt);

 /* main test */

 PR_Init(PR_USER_THREAD, PR_PRIORITY_NORMAL, 0);

 if (argc > 1) {
   loops = atoi(argv[1]);
 }
 if (loops == 0) {
   loops = 100;
 }
 if (debug_mode) {
   printf("Lock: Using %d loops\n", loops);
 }

 cpus = (argc < 3) ? 2 : atoi(argv[2]);
 if (cpus == 0) {
   cpus = 2;
 }
 if (debug_mode) {
   printf("Lock: Using %d cpu(s)\n", cpus);
 }

 for (cpu = 1; cpu <= cpus; ++cpu) {
   if (debug_mode) {
     printf("\nLockFile: Using %d CPU(s)\n", cpu);
   }
   PR_SetConcurrency(cpu);

   duration = Test("LockFile non-contentious locking/unlocking",
                   NonContentiousLock, loops, 0);
   (void)Test("LockFile contentious locking/unlocking", ContentiousLock, loops,
              duration);
 }

 PR_Delete(LOCKFILE); /* try to get rid of evidence */

 if (debug_mode) {
   printf("%s: test %s\n", "Lock(mutex) test",
          ((failed_already) ? "failed" : "passed"));
 }
 if (failed_already) {
   return 1;
 } else {
   return 0;
 }
} /* main */

/* testlock.c */