Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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
/***********************************************************************
** 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>
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;
}
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;
}
}
int main(int argc, char* argv[]) {
PRIntn rv;
PR_STDIO_INIT();
rv = PR_Initialize(RealMain, argc, argv, 0);
return rv;
} /* main */