akh morn

util/mornafah.c

@@ -6,43 +6,84 @@
 #include <topo.h>
 #include <immintrin.h>
 #include <x86intrin.h>
+#include <stdatomic.h>
+#include <string.h>
+#include <time.h>
+#include <math.h>
+#include <errno.h>
+#include <stdint.h>
 
 #include <sys/cpuset.h>
+#include <sys/sysctl.h>
 #include <pthread.h>
 #include <pthread_np.h>
 
-#define BUFFER_SIZE (1 * 1024 * 1024)
+#define BUFFER_SIZE (128 * 1024 * 1024)
+#define BUFFER_CNT (BUFFER_SIZE / sizeof(int))
 
 static _Atomic int flush = 0;
+static _Atomic uint64_t offset = 0;
 static int * remote_buffer = NULL;
-static uint64_t latencies[65536] = {0};
-static int times = 10;
+static uint64_t * latencies;
+static int times = 100;
 static int local_core = 0;
 static int remote_core = 1;
 static int cache_mode = 0;
+static int verbose = 0;
+static int random_access = 0;
+static uint64_t tsc_freq = 0;
+
+static inline uint64_t cyc2ns(uint64_t cyc)
+{
+	return (double)cyc / ((double)tsc_freq / 1000000000.0);
+}
+
+static inline uint64_t read_time(void)
+{
+	uint64_t l;
+	unsigned int a;
+	l = __rdtscp(&a);
+	_mm_lfence();
+	return l;
+}
 
 static void * local_thread(void *)
 {
-	int temp;
-	unsigned int dummy;
-	uint64_t start, end, base;
+	int temp, *addr;
+	uint64_t start, end;
 	printf("Local thread running...\n");
 	while(times > 0) {
+		if (random_access) {
+			// change offset
+			offset = (rand() % BUFFER_CNT) * sizeof(int);
+		}
+
 		flush = 1;
 		while(flush != 0) {
 		}
-		
-		_mm_clflush(remote_buffer);
 
-		start = __rdtscp(&dummy);
-		end = __rdtscp(&dummy);
-		base = end - start;
+		addr = (int *)((char *)remote_buffer + offset);
 
-		start = __rdtscp(&dummy);
-		temp = *remote_buffer;
-		end = __rdtscp(&dummy);
+		if (verbose > 1) {
+			printf("Local thread(%d): flushing %p.\n", local_core, addr);
+		}
 
-		latencies[times - 1] = end - start - base;
+		_mm_clflushopt(addr);
+		_mm_mfence();
+
+		atomic_signal_fence(memory_order_seq_cst);
+
+		start = read_time();
+		temp = *addr;
+		end = read_time();
+
+		atomic_signal_fence(memory_order_seq_cst);
+
+		if (verbose > 1) {
+			printf("Local thread(%d): read %p.\n", local_core, addr);
+		}
+
+		latencies[times - 1] = end - start;
 		times--;
 	}
 
@@ -52,14 +93,24 @@ static void * local_thread(void *)
 static void * remote_thread(void *)
 {
 	int temp;
+	int * addr;
 	printf("Remote thread running...\n");
 	while(1) {
 		while(flush == 0) {
 		}
+
+		addr = (int *)((char *)remote_buffer + offset);
+
 		if(cache_mode) {
-			temp = *remote_buffer;
+			temp = *addr;
+			_mm_mfence();
 		} else {
-			_mm_clflush(remote_buffer);
+			_mm_clflushopt(addr);
+			_mm_mfence();
+		}
+
+		if (verbose > 1) {
+			printf("Remote thread(%d): %p %s.\n", remote_core, addr, cache_mode ? "read into cache" : "flushed");
 		}
 
 		flush = 0;
@@ -72,7 +123,7 @@ int main(int argc, char * argv[])
 	{
 		int c;
 		// parse arguments
-		while ((c = getopt(argc, argv, "l:r:t:m:")) != -1) {
+		while ((c = getopt(argc, argv, "l:r:t:vR")) != -1) {
 			switch (c) {
 			case 'l':
 				local_core = atoi(optarg);
@@ -83,8 +134,11 @@ int main(int argc, char * argv[])
 			case 't':
 				times = atoi(optarg);
 				break;
-			case 'm':
-				cache_mode = atoi(optarg);
+			case 'R':
+				random_access = 1;
+				break;
+			case 'v':
+				verbose++;
 				break;
 			default:
 				exit(1);
@@ -92,6 +146,8 @@ int main(int argc, char * argv[])
 		}
 	}
 
+	srand(time(NULL));
+
 	// init topo
 	if (topo_init(1)) {
 		fprintf(stderr, "libtopo init failed!\n");
@@ -104,12 +160,24 @@ int main(int argc, char * argv[])
 		exit(1);
 	}
 
-	int remote_numa = topo_core_to_numa(remote_core);
-	int local_numa = topo_core_to_numa(local_core);
-	int total = times;
+	size_t sz = sizeof(tsc_freq);
+	int rc;
+	if ((rc = sysctlbyname("machdep.tsc_freq", &tsc_freq, &sz, NULL, 0)) < 0) {
+		fprintf(stderr,"failed to query tsc frequency via sysctl (%d)\n", errno);
+	} else {
+		fprintf(stdout,"system tsc frequency = %lu\n", tsc_freq);
+	}
 
-	remote_buffer = nms_alloc_static(remote_numa, BUFFER_SIZE);
-	*remote_buffer = 0xffa5be6c;
+	latencies = malloc(sizeof(uint64_t) * times);
+	const int remote_numa = topo_core_to_numa(remote_core);
+	const int local_numa = topo_core_to_numa(local_core);
+	const int total = times;
+
+	remote_buffer = nms_malloc(remote_numa, BUFFER_SIZE);
+	// fill with random values
+	for (int i = 0; i < BUFFER_SIZE; i++) {
+		remote_buffer[i] = rand();
+	}
 
 	pthread_attr_t lattr, rattr;
 	pthread_t lthread, rthread;
@@ -131,12 +199,39 @@ int main(int argc, char * argv[])
 	
 	pthread_join(lthread, NULL);
 
+	uint64_t min = UINT64_MAX;
+	uint64_t max = 0;
 	uint64_t sum = 0;
 	for (int i = total - 1; i >= 0; i--) {
-		printf("%lu\n", latencies[i]);
+		if (verbose) {
+			printf("%lu,\n", latencies[i]);
+		}
+		if (min > latencies[i]) {
+			min = latencies[i];
+		}
+		if (max < latencies[i]) {
+			max = latencies[i];
+		}
 		sum += latencies[i];
 	}
-	printf("Avg: %lu\n", sum / total);
+
+	double var = 0.0;
+	double avg = (double)sum / (double)total;
+	for (int i = total - 1; i >= 0; i--) {
+		var += pow(latencies[i] - avg, 2);
+	}
+	var = sqrt(var / avg);
+
+	printf("Avg: %lu cycles (%lu ns)\n"
+		   "Std: %lu cycles (%lu ns)\n"
+		   "Min: %lu cycles (%lu ns)\n"
+		   "Max: %lu cycles (%lu ns)\n", 
+		   (uint64_t)avg, cyc2ns((uint64_t)avg),
+		   (uint64_t)var, cyc2ns((uint64_t)var),
+		   min, cyc2ns(min),
+		   max, cyc2ns(max));
+
+	free(latencies);
 	return 0;
 }