From: adash <adash>
Date: Thu, 27 Aug 2009 23:13:48 +0000 (+0000)
Subject: check latency of a lock release and lock acquire
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a2e2687e8622dfeb2c37a37930c66cde42c7b285;p=IRC.git

check latency of a lock release and lock acquire
---

diff --git a/Robust/src/Benchmarks/SingleTM/MicroBenchmarks/lockLatency.c b/Robust/src/Benchmarks/SingleTM/MicroBenchmarks/lockLatency.c
new file mode 100644
index 00000000..0fe6068d
--- /dev/null
+++ b/Robust/src/Benchmarks/SingleTM/MicroBenchmarks/lockLatency.c
@@ -0,0 +1,114 @@
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <pthread.h>
+#include <sys/time.h>
+
+
+#define THREADS 2
+#define ITERATIONS 1000
+pthread_mutex_t LOCK;
+//pthread_mutex_t START;
+//Barrier variable
+pthread_barrier_t barr;
+int tottime = 0, time1, time2;
+
+int64_t timeInMS () //time in microsec
+{
+  struct timeval t;
+
+  gettimeofday(&t, NULL);
+  return (
+      (int64_t)t.tv_sec * 1000000 +
+      (int64_t)t.tv_usec
+      );
+}
+
+void * thd1 (
+    void * unused
+    ) {
+  // Wait till we may fire away
+  //pthread_mutex_lock(&START);
+  //pthread_mutex_unlock(&START);
+
+  int count = 0;
+  while(count<ITERATIONS) {
+    // Wait till we may fire away
+    int rc=pthread_barrier_wait(&barr);
+    if(rc != 0 && rc != PTHREAD_BARRIER_SERIAL_THREAD)
+    {
+      printf("Could not wait on barrier\n");
+      exit(-1);
+    }
+    pthread_mutex_lock(&LOCK);
+    // Delay 
+    sleep(2);
+    time1 = timeInMS();
+
+    pthread_mutex_unlock(&LOCK);
+    pthread_barrier_wait(&barr);
+    tottime += (time2-time1);
+    count++;
+  }
+}
+
+void * thd2 (
+    void *unused
+    ) {
+  // Wait till we may fire away
+  //pthread_mutex_lock(&START);
+  //pthread_mutex_unlock(&START);
+
+  int count = 0;
+  while(count<ITERATIONS) {
+    // Wait till we may fire away
+    int rc=pthread_barrier_wait(&barr);
+    if(rc != 0 && rc != PTHREAD_BARRIER_SERIAL_THREAD)
+    {
+      printf("Could not wait on barrier\n");
+      exit(-1);
+    }
+    // Delay 
+    sleep(1);
+    pthread_mutex_lock(&LOCK);
+    time2 = timeInMS();
+
+    pthread_mutex_unlock(&LOCK);
+    pthread_barrier_wait(&barr);
+    count++;
+  }
+}
+
+
+int main (
+    int argc,
+    char ** argv
+    ) {
+  int64_t start;
+  pthread_t t1;
+  pthread_t t2;
+  int64_t myTime;
+
+  // Barrier initialization
+  if(pthread_barrier_init(&barr, NULL, THREADS))
+  {
+    printf("Could not create a barrier\n");
+    return -1;
+  }
+
+  pthread_mutex_init(&LOCK, NULL);   
+  //pthread_mutex_init(&START, NULL);   
+
+  //pthread_mutex_lock(&START);
+  pthread_create(&t1, NULL, thd1, NULL);
+  pthread_create(&t2, NULL, thd2, NULL);
+
+  pthread_join(t1, NULL);
+  pthread_join(t2, NULL);
+
+  //pthread_mutex_unlock(&START);
+
+  int locklatency = tottime/ITERATIONS;
+  printf("locklatency was %u micro secs\n", locklatency);
+  return 0;
+}