diff --git a/tools/perf/bench/bench.h b/tools/perf/bench/bench.h
index 80208ac..7101092 100644
--- a/tools/perf/bench/bench.h
+++ b/tools/perf/bench/bench.h
@@ -2,6 +2,10 @@
 #ifndef BENCH_H
 #define BENCH_H
 
+#include <sys/time.h>
+
+extern struct timeval bench__start, bench__end, bench__runtime;
+
 /*
  * The madvise transparent hugepage constants were added in glibc
  * 2.13. For compatibility with older versions of glibc, define these
diff --git a/tools/perf/bench/futex-hash.c b/tools/perf/bench/futex-hash.c
index 58ae6ed..0f683fe 100644
--- a/tools/perf/bench/futex-hash.c
+++ b/tools/perf/bench/futex-hash.c
@@ -35,7 +35,7 @@ static unsigned int nfutexes = 1024;
 static bool fshared = false, done = false, silent = false;
 static int futex_flag = 0;
 
-struct timeval start, end, runtime;
+struct timeval bench__start, bench__end, bench__runtime;
 static pthread_mutex_t thread_lock;
 static unsigned int threads_starting;
 static struct stats throughput_stats;
@@ -101,8 +101,8 @@ static void toggle_done(int sig __maybe_unused,
 {
 	/* inform all threads that we're done for the day */
 	done = true;
-	gettimeofday(&end, NULL);
-	timersub(&end, &start, &runtime);
+	gettimeofday(&bench__end, NULL);
+	timersub(&bench__end, &bench__start, &bench__runtime);
 }
 
 static void print_summary(void)
@@ -112,7 +112,7 @@ static void print_summary(void)
 
 	printf("%sAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n",
 	       !silent ? "\n" : "", avg, rel_stddev_stats(stddev, avg),
-	       (int) runtime.tv_sec);
+	       (int)bench__runtime.tv_sec);
 }
 
 int bench_futex_hash(int argc, const char **argv)
@@ -156,7 +156,7 @@ int bench_futex_hash(int argc, const char **argv)
 
 	threads_starting = nthreads;
 	pthread_attr_init(&thread_attr);
-	gettimeofday(&start, NULL);
+	gettimeofday(&bench__start, NULL);
 	for (i = 0; i < nthreads; i++) {
 		worker[i].tid = i;
 		worker[i].futex = calloc(nfutexes, sizeof(*worker[i].futex));
@@ -199,7 +199,7 @@ int bench_futex_hash(int argc, const char **argv)
 	pthread_mutex_destroy(&thread_lock);
 
 	for (i = 0; i < nthreads; i++) {
-		unsigned long t = worker[i].ops/runtime.tv_sec;
+		unsigned long t = worker[i].ops / bench__runtime.tv_sec;
 		update_stats(&throughput_stats, t);
 		if (!silent) {
 			if (nfutexes == 1)
diff --git a/tools/perf/bench/futex-lock-pi.c b/tools/perf/bench/futex-lock-pi.c
index 08653ae..58711b7 100644
--- a/tools/perf/bench/futex-lock-pi.c
+++ b/tools/perf/bench/futex-lock-pi.c
@@ -34,7 +34,6 @@ static bool silent = false, multi = false;
 static bool done = false, fshared = false;
 static unsigned int ncpus, nthreads = 0;
 static int futex_flag = 0;
-struct timeval start, end, runtime;
 static pthread_mutex_t thread_lock;
 static unsigned int threads_starting;
 static struct stats throughput_stats;
@@ -61,7 +60,7 @@ static void print_summary(void)
 
 	printf("%sAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n",
 	       !silent ? "\n" : "", avg, rel_stddev_stats(stddev, avg),
-	       (int) runtime.tv_sec);
+	       (int)bench__runtime.tv_sec);
 }
 
 static void toggle_done(int sig __maybe_unused,
@@ -70,8 +69,8 @@ static void toggle_done(int sig __maybe_unused,
 {
 	/* inform all threads that we're done for the day */
 	done = true;
-	gettimeofday(&end, NULL);
-	timersub(&end, &start, &runtime);
+	gettimeofday(&bench__end, NULL);
+	timersub(&bench__end, &bench__start, &bench__runtime);
 }
 
 static void *workerfn(void *arg)
@@ -178,7 +177,7 @@ int bench_futex_lock_pi(int argc, const char **argv)
 
 	threads_starting = nthreads;
 	pthread_attr_init(&thread_attr);
-	gettimeofday(&start, NULL);
+	gettimeofday(&bench__start, NULL);
 
 	create_threads(worker, thread_attr);
 	pthread_attr_destroy(&thread_attr);
@@ -204,7 +203,7 @@ int bench_futex_lock_pi(int argc, const char **argv)
 	pthread_mutex_destroy(&thread_lock);
 
 	for (i = 0; i < nthreads; i++) {
-		unsigned long t = worker[i].ops/runtime.tv_sec;
+		unsigned long t = worker[i].ops / bench__runtime.tv_sec;
 
 		update_stats(&throughput_stats, t);
 		if (!silent)