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cvar.c

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Netscape Portable Runtime (NSPR).
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998-2000
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

/***********************************************************************
**  1996 - Netscape Communications Corporation
**
** Name: cvar.c
**
** Description: Tests Condition Variable Operations 
**
** Modification History:
** 13-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.
** 12-June-97 Revert to return code 0 and 1.
***********************************************************************/

/***********************************************************************
** Includes
***********************************************************************/

#include "nspr.h"

/* Used to get the command line option */
#include "plgetopt.h"

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

#ifdef XP_MAC
#include "prlog.h"
#define printf PR_LogPrint
extern void SetupMacPrintfLog(char *logFile);
#endif

PRMonitor *mon;
#define DEFAULT_COUNT   1000
PRInt32 count = 0;
PRIntn debug_mode;

#define kQSIZE    1

typedef struct {
      PRLock            *bufLock;
      int               startIdx;
      int               numFull;
      PRCondVar   *notFull;
      PRCondVar   *notEmpty;
      void        *data[kQSIZE];
} CircBuf;

static PRBool failed = PR_FALSE;

/*
** NewCB creates and initializes a new circular buffer.
*/
static CircBuf* NewCB(void)
{
      CircBuf           *cbp;
      
      cbp = PR_NEW(CircBuf);
      if (cbp == NULL)
            return (NULL);
            
      cbp->bufLock      = PR_NewLock();
      cbp->startIdx     = 0;
      cbp->numFull      = 0;
      cbp->notFull      = PR_NewCondVar(cbp->bufLock);
      cbp->notEmpty     = PR_NewCondVar(cbp->bufLock);
      
      return (cbp);
}

/*
** DeleteCB frees a circular buffer.
*/
static void DeleteCB(CircBuf *cbp)
{
      PR_DestroyLock(cbp->bufLock);
      PR_DestroyCondVar(cbp->notFull);
      PR_DestroyCondVar(cbp->notEmpty);
      PR_DELETE(cbp);
}


/*
** PutCBData puts new data on the queue.  If the queue is full, it waits 
** until there is room.
*/
static void PutCBData(CircBuf *cbp, void *data)
{
      PR_Lock(cbp->bufLock);
      /* wait while the buffer is full */
      while (cbp->numFull == kQSIZE)
            PR_WaitCondVar(cbp->notFull,PR_INTERVAL_NO_TIMEOUT);
      cbp->data[(cbp->startIdx + cbp->numFull) % kQSIZE] = data;
      cbp->numFull += 1;
      
      /* let a waiting reader know that there is data */
      PR_NotifyCondVar(cbp->notEmpty);
      PR_Unlock(cbp->bufLock);

}


/*
** GetCBData gets the oldest data on the queue.  If the queue is empty, it waits 
** until new data appears.
*/
static void* GetCBData(CircBuf *cbp)
{
      void *data;
      
      PR_Lock(cbp->bufLock);
      /* wait while the buffer is empty */
      while (cbp->numFull == 0)
            PR_WaitCondVar(cbp->notEmpty,PR_INTERVAL_NO_TIMEOUT);
      data = cbp->data[cbp->startIdx];
      cbp->startIdx =(cbp->startIdx + 1) % kQSIZE;
      cbp->numFull -= 1;
      
      /* let a waiting writer know that there is room */
      PR_NotifyCondVar(cbp->notFull);
      PR_Unlock(cbp->bufLock);
      
      return (data);
}


/************************************************************************/

static int alive;

static void PR_CALLBACK CXReader(void *arg)
{
      CircBuf *cbp = (CircBuf *)arg;
    PRInt32 i, n;
    void *data;

    n = count / 2;
    for (i = 0; i < n; i++) {
            data = GetCBData(cbp);
            if ((int)data != i)
            if (debug_mode) printf("data mismatch at for i = %d usec\n", i);
    }
 
    PR_EnterMonitor(mon);
    --alive;
    PR_Notify(mon);
    PR_ExitMonitor(mon);
}

static void PR_CALLBACK CXWriter(void *arg)
{
      CircBuf *cbp = (CircBuf *)arg;
    PRInt32 i, n;

    n = count / 2;
    for (i = 0; i < n; i++)
            PutCBData(cbp, (void *)i);

    PR_EnterMonitor(mon);
    --alive;
    PR_Notify(mon);
    PR_ExitMonitor(mon);
}

static void CondWaitContextSwitch(PRThreadScope scope1, PRThreadScope scope2)
{
    PRThread *t1, *t2;
      CircBuf *cbp;

    PR_EnterMonitor(mon);

    alive = 2;

      cbp =  NewCB();

      t1 = PR_CreateThread(PR_USER_THREAD,
                              CXReader, cbp, 
                              PR_PRIORITY_NORMAL,
                              scope1,
                          PR_UNJOINABLE_THREAD,
                              0);
      PR_ASSERT(t1);
      t2 = PR_CreateThread(PR_USER_THREAD,
                              CXWriter, cbp, 
                              PR_PRIORITY_NORMAL,
                              scope2,
                          PR_UNJOINABLE_THREAD,
                              0);
      PR_ASSERT(t2);

    /* Wait for both of the threads to exit */
    while (alive) {
      PR_Wait(mon, PR_INTERVAL_NO_TIMEOUT);
    }

      DeleteCB(cbp);

    PR_ExitMonitor(mon);
}

static void CondWaitContextSwitchUU(void)
{
    CondWaitContextSwitch(PR_LOCAL_THREAD, PR_LOCAL_THREAD);
}

static void CondWaitContextSwitchUK(void)
{
    CondWaitContextSwitch(PR_LOCAL_THREAD, PR_GLOBAL_THREAD);
}

static void CondWaitContextSwitchKK(void)
{
    CondWaitContextSwitch(PR_GLOBAL_THREAD, PR_GLOBAL_THREAD);
}

/************************************************************************/

static void Measure(void (*func)(void), const char *msg)
{
    PRIntervalTime start, stop;
    double d;

    start = PR_IntervalNow();
    (*func)();
    stop = PR_IntervalNow();

    d = (double)PR_IntervalToMicroseconds(stop - start);

    if (debug_mode) printf("%40s: %6.2f usec\n", msg, d / count);

    if (0 ==  d) failed = PR_TRUE;
}

static PRIntn PR_CALLBACK RealMain(int argc, char **argv)
{
      /* 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] [-c n]
      */
      PLOptStatus os;
      PLOptState *opt = PL_CreateOptState(argc, argv, "dc:");
      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;
        case 'c':  /* loop count */
            count = atoi(opt->value);
            break;
         default:
            break;
        }
    }
      PL_DestroyOptState(opt);

    if (0 == count) count = DEFAULT_COUNT;

#ifdef XP_MAC
      SetupMacPrintfLog("cvar.log");
      debug_mode = 1;
#endif

    mon = PR_NewMonitor();

    Measure(CondWaitContextSwitchUU, "cond var wait context switch- user/user");
    Measure(CondWaitContextSwitchUK, "cond var wait context switch- user/kernel");
    Measure(CondWaitContextSwitchKK, "cond var wait context switch- kernel/kernel");

      PR_DestroyMonitor(mon);

      if (debug_mode) printf("%s\n", (failed) ? "FAILED" : "PASSED");

      if(failed)
            return 1;
      else
            return 0;
}


PRIntn main(PRIntn argc, char *argv[])
{
    PRIntn rv;
    
    PR_STDIO_INIT();
    rv = PR_Initialize(RealMain, argc, argv, 0);
    return rv;
}  /* main */

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