tests: benchmark: improve benchmark scalability accuracy

[deliverable/lttng-ust.git] / tests / benchmark / bench.c

diff --git a/tests/benchmark/bench.c b/tests/benchmark/bench.c
index 77f53a1532f9a977d149acde14c95974be0a2889..d15896cccd38dad1f5fdb89cc03920c2a95cf58c 100644 (file)
--- a/tests/benchmark/bench.c
+++ b/tests/benchmark/bench.c
@@ -4,6 +4,7 @@
  * LTTng Userspace Tracer (UST) - benchmark tool
  *
  * Copyright 2010 - Douglas Santos <douglas.santos@polymtl.ca>
+ * Copyright 2021 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
  * 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
@@ -34,8 +35,22 @@
 #include "ust_tests_benchmark.h"
 #endif
 
-static int nr_cpus;
-static unsigned long nr_events;
+#define printf_verbose(fmt, args...)           \
+       do {                                    \
+               if (verbose_mode)               \
+                       printf(fmt, ## args);   \
+       } while (0)
+
+static int verbose_mode;
+
+struct thread_counter {
+       unsigned long long nr_loops;
+};
+
+static int nr_threads;
+static unsigned long duration;
+
+static volatile int test_go, test_stop;
 
 void do_stuff(void)
 {
@@ -53,21 +68,33 @@ void do_stuff(void)
 
 void *function(void *arg)
 {
-       unsigned long i;
+       unsigned long long nr_loops = 0;
+       struct thread_counter *thread_counter = arg;
 
-       for (i = 0; i < nr_events; i++) {
+       while (!test_go)
+               cmm_barrier();
+
+       for (;;) {
                do_stuff();
+               nr_loops++;
+               if (test_stop)
+                       break;
        }
+       thread_counter->nr_loops = nr_loops;
        return NULL;
 }
 
 void usage(char **argv) {
-       printf("Usage: %s nr_cpus nr_events\n", argv[0]);
+       printf("Usage: %s nr_threads duration(s) <OPTIONS>\n", argv[0]);
+       printf("OPTIONS:\n");
+       printf("        [-v] (verbose output)\n");
+       printf("\n");
 }
 
-
 int main(int argc, char **argv)
 {
+       unsigned long long total_loops = 0;
+       unsigned long i_thr;
        void *retval;
        int i;
 
@@ -76,25 +103,53 @@ int main(int argc, char **argv)
                exit(1);
        }
 
-       nr_cpus = atoi(argv[1]);
-       printf("using %d processor(s)\n", nr_cpus);
+       nr_threads = atoi(argv[1]);
+       duration = atol(argv[2]);
+
+       for (i = 3; i < argc; i++) {
+               if (argv[i][0] != '-')
+                       continue;
+               switch (argv[i][1]) {
+               case 'v':
+                       verbose_mode = 1;
+                       break;
+               }
+       }
+
+       printf_verbose("using %d thread(s)\n", nr_threads);
+       printf_verbose("for a duration of %lds\n", duration);
 
-       nr_events = atol(argv[2]);
-       printf("using %ld events per cpu\n", nr_events);
+       pthread_t thread[nr_threads];
+       struct thread_counter thread_counter[nr_threads];
 
-       pthread_t thread[nr_cpus];
-       for (i = 0; i < nr_cpus; i++) {
-               if (pthread_create(&thread[i], NULL, function, NULL)) {
+       for (i = 0; i < nr_threads; i++) {
+               thread_counter[i].nr_loops = 0;
+               if (pthread_create(&thread[i], NULL, function, &thread_counter[i])) {
                        fprintf(stderr, "thread create %d failed\n", i);
                        exit(1);
                }
        }
 
-       for (i = 0; i < nr_cpus; i++) {
+       test_go = 1;
+
+       for (i_thr = 0; i_thr < duration; i_thr++) {
+               sleep(1);
+               if (verbose_mode) {
+                       fwrite(".", sizeof(char), 1, stdout);
+                       fflush(stdout);
+               }
+       }
+       printf_verbose("\n");
+
+       test_stop = 1;
+
+       for (i = 0; i < nr_threads; i++) {
                if (pthread_join(thread[i], &retval)) {
                        fprintf(stderr, "thread join %d failed\n", i);
                        exit(1);
                }
+               total_loops += thread_counter[i].nr_loops;
        }
+       printf("Number of loops: %llu\n", total_loops);
        return 0;
 }