/*
* Copyright (C) 2010 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <pthread.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
/* Posix states that EDEADLK should be returned in case a deadlock condition
* is detected with a PTHREAD_MUTEX_ERRORCHECK lock() or trylock(), but
* GLibc returns EBUSY instead.
*/
#ifdef HOST
# define ERRNO_PTHREAD_EDEADLK EBUSY
#else
# define ERRNO_PTHREAD_EDEADLK EDEADLK
#endif
static void __attribute__((noreturn))
panic(const char* func, const char* format, ...)
{
va_list args;
fprintf(stderr, "%s: ", func);
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
fprintf(stderr, "\n");
exit(1);
}
#define PANIC(...) panic(__FUNCTION__,__VA_ARGS__)
static void __attribute__((noreturn))
error(int errcode, const char* func, const char* format, ...)
{
va_list args;
fprintf(stderr, "%s: ", func);
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
fprintf(stderr, " error=%d: %s\n", errcode, strerror(errcode));
exit(1);
}
/* return current time in seconds as floating point value */
static double
time_now(void)
{
struct timespec ts[1];
clock_gettime(CLOCK_MONOTONIC, ts);
return (double)ts->tv_sec + ts->tv_nsec/1e9;
}
static void
time_sleep(double delay)
{
struct timespec ts;
int ret;
ts.tv_sec = (time_t)delay;
ts.tv_nsec = (long)((delay - ts.tv_sec)*1e9);
do {
ret = nanosleep(&ts, &ts);
} while (ret < 0 && errno == EINTR);
}
#define ERROR(errcode,...) error((errcode),__FUNCTION__,__VA_ARGS__)
#define TZERO(cond) \
{ int _ret = (cond); if (_ret != 0) ERROR(_ret,"%d:%s", __LINE__, #cond); }
#define TTRUE(cond) \
{ if (!(cond)) PANIC("%d:%s", __LINE__, #cond); }
#define TFALSE(cond) \
{ if (!!(cond)) PANIC("%d:%s", __LINE__, #cond); }
#define TEXPECT_INT(cond,val) \
{ int _ret = (cond); if (_ret != (val)) PANIC("%d:%s returned %d (%d expected)", __LINE__, #cond, _ret, (val)); }
/* perform a simple init/lock/unlock/destroy test on a mutex of given attributes */
static void do_test_mutex_1(pthread_mutexattr_t *attr)
{
int ret;
pthread_mutex_t lock[1];
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_lock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
}
static void set_mutexattr_type(pthread_mutexattr_t *attr, int type)
{
int newtype;
TZERO(pthread_mutexattr_settype(attr, type));
newtype = ~type;
TZERO(pthread_mutexattr_gettype(attr, &newtype));
TEXPECT_INT(newtype,type);
}
/* simple init/lock/unlock/destroy on all mutex types */
static void do_test_1(void)
{
int ret, type;
pthread_mutexattr_t attr[1];
do_test_mutex_1(NULL);
/* non-shared version */
TZERO(pthread_mutexattr_init(attr));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_1(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_1(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_1(attr);
TZERO(pthread_mutexattr_destroy(attr));
/* shared version */
TZERO(pthread_mutexattr_init(attr));
TZERO(pthread_mutexattr_setpshared(attr, PTHREAD_PROCESS_SHARED));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_1(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_1(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_1(attr);
TZERO(pthread_mutexattr_destroy(attr));
}
/* perform init/trylock/unlock/destroy then init/lock/trylock/destroy */
static void do_test_mutex_2(pthread_mutexattr_t *attr)
{
pthread_mutex_t lock[1];
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TEXPECT_INT(pthread_mutex_trylock(lock),EBUSY);
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
}
static void do_test_mutex_2_rec(pthread_mutexattr_t *attr)
{
pthread_mutex_t lock[1];
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TZERO(pthread_mutex_trylock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
}
static void do_test_mutex_2_chk(pthread_mutexattr_t *attr)
{
pthread_mutex_t lock[1];
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
TZERO(pthread_mutex_init(lock, attr));
TZERO(pthread_mutex_trylock(lock));
TEXPECT_INT(pthread_mutex_trylock(lock),ERRNO_PTHREAD_EDEADLK);
TZERO(pthread_mutex_unlock(lock));
TZERO(pthread_mutex_destroy(lock));
}
static void do_test_2(void)
{
pthread_mutexattr_t attr[1];
do_test_mutex_2(NULL);
/* non-shared version */
TZERO(pthread_mutexattr_init(attr));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_2(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_2_rec(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_2_chk(attr);
TZERO(pthread_mutexattr_destroy(attr));
/* shared version */
TZERO(pthread_mutexattr_init(attr));
TZERO(pthread_mutexattr_setpshared(attr, PTHREAD_PROCESS_SHARED));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_2(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_2_rec(attr);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_2_chk(attr);
TZERO(pthread_mutexattr_destroy(attr));
}
/* This is more complex example to test contention of mutexes.
* Essentially, what happens is this:
*
* - main thread creates a mutex and locks it
* - it then creates thread 1 and thread 2
*
* - it then record the current time, sleep for a specific 'waitDelay'
* then unlock the mutex.
*
* - thread 1 locks() the mutex. It shall be stopped for a least 'waitDelay'
* seconds. It then unlocks the mutex.
*
* - thread 2 trylocks() the mutex. In case of failure (EBUSY), it waits
* for a small amount of time (see 'spinDelay') and tries again, until
* it succeeds. It then unlocks the mutex.
*
* The goal of this test is to verify that thread 1 has been stopped
* for a sufficiently long time, and that thread 2 has been spinning for
* the same minimum period. There is no guarantee as to which thread is
* going to acquire the mutex first.
*/
typedef struct {
pthread_mutex_t mutex[1];
double t0;
double waitDelay;
double spinDelay;
} Test3State;
static void* do_mutex_test_3_t1(void* arg)
{
Test3State *s = arg;
double t1;
TZERO(pthread_mutex_lock(s->mutex));
t1 = time_now();
//DEBUG ONLY: printf("t1-s->t0=%g waitDelay=%g\n", t1-s->t0, s->waitDelay);
TTRUE((t1-s->t0) >= s->waitDelay);
TZERO(pthread_mutex_unlock(s->mutex));
return NULL;
}
static void* do_mutex_test_3_t2(void* arg)
{
Test3State *s = arg;
double t1;
for (;;) {
int ret = pthread_mutex_trylock(s->mutex);
if (ret == 0)
break;
if (ret == EBUSY) {
time_sleep(s->spinDelay);
continue;
}
}
t1 = time_now();
TTRUE((t1-s->t0) >= s->waitDelay);
TZERO(pthread_mutex_unlock(s->mutex));
return NULL;
}
static void do_test_mutex_3(pthread_mutexattr_t *attr, double delay)
{
Test3State s[1];
pthread_t th1, th2;
void* dummy;
TZERO(pthread_mutex_init(s->mutex, attr));
s->waitDelay = delay;
s->spinDelay = delay/20.;
TZERO(pthread_mutex_lock(s->mutex));
pthread_create(&th1, NULL, do_mutex_test_3_t1, s);
pthread_create(&th2, NULL, do_mutex_test_3_t2, s);
s->t0 = time_now();
time_sleep(delay);
TZERO(pthread_mutex_unlock(s->mutex));
TZERO(pthread_join(th1, &dummy));
TZERO(pthread_join(th2, &dummy));
}
static void do_test_3(double delay)
{
pthread_mutexattr_t attr[1];
do_test_mutex_3(NULL, delay);
/* non-shared version */
TZERO(pthread_mutexattr_init(attr));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_3(attr, delay);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_3(attr, delay);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_3(attr, delay);
TZERO(pthread_mutexattr_destroy(attr));
/* shared version */
TZERO(pthread_mutexattr_init(attr));
TZERO(pthread_mutexattr_setpshared(attr, PTHREAD_PROCESS_SHARED));
set_mutexattr_type(attr, PTHREAD_MUTEX_NORMAL);
do_test_mutex_3(attr, delay);
set_mutexattr_type(attr, PTHREAD_MUTEX_RECURSIVE);
do_test_mutex_3(attr, delay);
set_mutexattr_type(attr, PTHREAD_MUTEX_ERRORCHECK);
do_test_mutex_3(attr, delay);
TZERO(pthread_mutexattr_destroy(attr));
}
int main(void)
{
do_test_1();
do_test_2();
do_test_3(0.1);
return 0;
}