site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com pthread_t t1, t2;         int iX = 0;         assert(!pthread_create(&t1, NULL, test_atomic_inc, &iX));         assert(!pthread_create(&t2, NULL, test_atomic_dec, &iX));         assert(!pthread_join(t1, NULL));         assert(!pthread_join(t2, NULL));         assert(!iX); matt. On Sep 19, 2004, at 8:22 AM, jmzorko@mac.com wrote: #include <pthread.h> #include <iostream> using namespace std; typedef int AtomicCountType; // code lifted from linux asm volatile( "1: lwarx %0,0,%1\n" " addic %0,%0,1\n" // addic allows r0, addi doesn't " stwcx. %0,0,%1\n" " bne- 1b" : "=&r" (tmp) : "r" ( p ) : "cc", "memory"); return( tmp ); } // code lifted from linux asm volatile( "2: lwarx %0,0,%1\n" " addic %0,%0,-1\n" // addic allows r0, addi doesn't " stwcx. %0,0,%1\n" " bne- 2b" : "=&r" (tmp) : "r" ( p ) : "cc", "memory"); return( tmp ); } inline static AtomicCountType AtomicBump( volatile AtomicCountType *p, AtomicCountType AddMe ) { int tmp; // code lifted from linux asm volatile( "3: lwarx %0,0,%1\n" " addic %0,%0,( AddMe )\n" // addic allows r0, addi doesn't " stwcx. %0,0,%1\n" " bne- 3b" : "=&r" (tmp) : "r" ( p ) : "cc", "memory"); return( tmp ); } void test_atomic_inc( void *pX ) { int *piX = static_cast< int * >( pX ); for ( int iIndex = 0; iIndex < 1000000000; iIndex ++ ) { //AtomicIncrement( piX ); ( *piX ) ++; } pthread_exit( 0 ); } void test_atomic_dec( void *pX ) { int *piX = static_cast< int * >( pX ); for ( int iIndex = 0; iIndex < 1000000000; iIndex ++ ) { //AtomicDecrement( piX ); ( *piX ) --; } pthread_exit( 0 ); } int main( int iArgc, char *pcArgv[] ) { // our one true int ... int iX = 0; // ... and some other stuff int iStatus = 0; // create 500 threads, half doing incs, half doing decs pthread_t threads[ 500 ] = { 0 }; for ( int iIndex = 0; iIndex < 500; iIndex ++ ) { int iCreatedOK = pthread_create( &threads[ iIndex ], NULL, iIndex % 2 == 0 ? test_atomic_inc : test_atomic_dec, &iX ); if ( iCreatedOK != 0 ) { cout << "can't make thread " << iIndex << "\n"; break; } else { pthread_join( threads[ iIndex ], ( void ** )&iStatus ); } } // test to make sure iX is still 0 i.e. operations were really atomic cout << "test " << ( iX == 0 ? "passed: " : "failed: " ) << iX << "\n"; pthread_exit( 0 ); } _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... You're not creating 500 simultaneous threads, since pthread_join waits for the thread to complete and the loop does create, join, create, join... Also, you don't need 500 threads to test atomicity. Try just creating 2 threads in main(), like: inline static AtomicCountType AtomicIncrement( volatile AtomicCountType *p ) { int tmp; inline static AtomicCountType AtomicDecrement( volatile AtomicCountType *p ) { int tmp; This email sent to site_archiver@lists.apple.com