Changeset bdfc032 for benchmark/schedint/pthreads.c

Timestamp:

Feb 4, 2020, 11:35:26 AM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

eef8dfb

Parents:

aefb247 (diff), 4f7b418 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' into dkobets-vector

File:

• benchmark/schedint/pthreads.c (modified) (1 diff)

benchmark/schedint/pthreads.c

@@ -4 +4 @@
 #include "bench.h"
 
-int argc;
-char** argv;
 volatile int go = 0;
 
+pthread_mutex_t m;
 pthread_cond_t c;
-pthread_mutex_t m;
 
 void __attribute__((noinline)) call() {
-        pthread_mutex_lock(&m);
-        pthread_cond_signal(&c);
-        pthread_mutex_unlock(&m);
+        pthread_mutex_lock( &m );
+        pthread_cond_signal( &c );
+        pthread_mutex_unlock( &m );
 }
 
-int  __attribute__((noinline)) wait() {
+void __attribute__((noinline)) wait() {
         pthread_mutex_lock(&m);
         go = 1;
+        for ( size_t i = 0; i < times; i++ ) {
+                pthread_cond_wait( &c, &m );
+        }
+        go = 0;
+        pthread_mutex_unlock( &m );
+}
+
+void * thread_main( __attribute__((unused)) void * arg ) {
+        while ( go == 0 ) { sched_yield(); } // waiter must start first
+        // barging for lock acquire => may not execute N times
         BENCH(
-                for (size_t i = 0; i < n; i++) {
-                        pthread_cond_wait(&c, &m);
-                },
+                while ( go == 1 ) { call(); },
                 result
         )
-
-        printf("%g\n", result);
-        go = 0;
-        pthread_mutex_unlock(&m);
-        return 0;
-}
-
-void* thread_main(__attribute__((unused)) void * arg ) {
-        while(go == 0) { sched_yield(); }
-        while(go == 1) { call(); }
+        printf( "%g\n", result );
         return NULL;
 }
 
-int main(__attribute__((unused)) int argc, __attribute__((unused)) char* argv[]) {
+int main( int argc, char * argv[] ) {
+        BENCH_START()
         pthread_t thread;
-        if (pthread_create(&thread, NULL, thread_main, NULL) < 0) {
+        if ( pthread_create( &thread, NULL, thread_main, NULL ) < 0 ) {
                 perror( "failure" );
                 return 1;
         }
         wait();
-        if (pthread_join( thread, NULL) < 0) {
+        if ( pthread_join( thread, NULL ) < 0 ) {
                 perror( "failure" );
                 return 1;
         }
-        return 0;
 }
+
+// Local Variables: //
+// tab-width: 4 //
+// End: //