mariadb/unittest/mysys/my_atomic-t.c
lars@mysql.com 78a9adb659 Changed the number of test iterations since this makes test time
go from 623 seconds to 11 seconds on AMD64.
This is because we have no native atomic implementation on AMD64, 
so the rwlock-based implementation is used, which is  a bit slow.  
It will be probably be optimized for AMD64 quite soon, but for now 
this test case will do fewer iterations.
2006-06-30 11:31:43 +02:00

179 lines
4.4 KiB
C

/* Copyright (C) 2006 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#include <my_global.h>
#include <tap.h>
#include <my_sys.h>
#include <my_atomic.h>
int32 a32,b32,c32;
my_atomic_rwlock_t rwl;
pthread_attr_t thr_attr;
pthread_mutex_t mutex;
pthread_cond_t cond;
int N;
/* add and sub a random number in a loop. Must get 0 at the end */
pthread_handler_t test_atomic_add_handler(void *arg)
{
int m=*(int *)arg;
int32 x;
for (x=((int)(&m)); m ; m--)
{
x=x*m+0x87654321;
my_atomic_rwlock_wrlock(&rwl);
my_atomic_add32(&a32, x);
my_atomic_rwlock_wrunlock(&rwl);
my_atomic_rwlock_wrlock(&rwl);
my_atomic_add32(&a32, -x);
my_atomic_rwlock_wrunlock(&rwl);
}
pthread_mutex_lock(&mutex);
N--;
if (!N) pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
return 0;
}
/*
1. generate thread number 0..N-1 from b32
2. add it to a32
3. swap thread numbers in c32
4. (optionally) one more swap to avoid 0 as a result
5. subtract result from a32
must get 0 in a32 at the end
*/
pthread_handler_t test_atomic_swap_handler(void *arg)
{
int m=*(int *)arg;
int32 x;
my_atomic_rwlock_wrlock(&rwl);
x=my_atomic_add32(&b32, 1);
my_atomic_rwlock_wrunlock(&rwl);
my_atomic_rwlock_wrlock(&rwl);
my_atomic_add32(&a32, x);
my_atomic_rwlock_wrunlock(&rwl);
for (; m ; m--)
{
my_atomic_rwlock_wrlock(&rwl);
x=my_atomic_swap32(&c32, x);
my_atomic_rwlock_wrunlock(&rwl);
}
if (!x)
{
my_atomic_rwlock_wrlock(&rwl);
x=my_atomic_swap32(&c32, x);
my_atomic_rwlock_wrunlock(&rwl);
}
my_atomic_rwlock_wrlock(&rwl);
my_atomic_add32(&a32, -x);
my_atomic_rwlock_wrunlock(&rwl);
pthread_mutex_lock(&mutex);
N--;
if (!N) pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
return 0;
}
/*
same as test_atomic_add_handler, but my_atomic_add32 is emulated with
(slower) my_atomic_cas32
*/
pthread_handler_t test_atomic_cas_handler(void *arg)
{
int m=*(int *)arg, ok;
int32 x,y;
for (x=((int)(&m)); m ; m--)
{
my_atomic_rwlock_wrlock(&rwl);
y=my_atomic_load32(&a32);
my_atomic_rwlock_wrunlock(&rwl);
x=x*m+0x87654321;
do {
my_atomic_rwlock_wrlock(&rwl);
ok=my_atomic_cas32(&a32, &y, y+x);
my_atomic_rwlock_wrunlock(&rwl);
} while (!ok);
do {
my_atomic_rwlock_wrlock(&rwl);
ok=my_atomic_cas32(&a32, &y, y-x);
my_atomic_rwlock_wrunlock(&rwl);
} while (!ok);
}
pthread_mutex_lock(&mutex);
N--;
if (!N) pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
return 0;
}
void test_atomic(const char *test, pthread_handler handler, int n, int m)
{
pthread_t t;
ulonglong now=my_getsystime();
a32= 0;
b32= 0;
c32= 0;
diag("Testing %s with %d threads, %d iterations... ", test, n, m);
for (N=n ; n ; n--)
pthread_create(&t, &thr_attr, handler, &m);
pthread_mutex_lock(&mutex);
while (N)
pthread_cond_wait(&cond, &mutex);
pthread_mutex_unlock(&mutex);
now=my_getsystime()-now;
ok(a32 == 0, "tested %s in %g secs", test, ((double)now)/1e7);
}
int main()
{
int err;
diag("N CPUs: %d", my_getncpus());
err= my_atomic_initialize();
plan(4);
ok(err == 0, "my_atomic_initialize() returned %d", err);
pthread_attr_init(&thr_attr);
pthread_attr_setdetachstate(&thr_attr,PTHREAD_CREATE_DETACHED);
pthread_mutex_init(&mutex, 0);
pthread_cond_init(&cond, 0);
my_atomic_rwlock_init(&rwl);
test_atomic("my_atomic_add32", test_atomic_add_handler, 100,10000);
test_atomic("my_atomic_swap32", test_atomic_swap_handler, 100,10000);
test_atomic("my_atomic_cas32", test_atomic_cas_handler, 100,10000);
pthread_mutex_destroy(&mutex);
pthread_cond_destroy(&cond);
pthread_attr_destroy(&thr_attr);
my_atomic_rwlock_destroy(&rwl);
return exit_status();
}