Noticed with gcc 10 (fedora rawhide) that those variables were not being
declared as static, so end up with:
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  make[4]: *** [/git/perf/tools/build/Makefile.build:145: /tmp/build/perf/bench/perf-in.o] Error 1
Prefix those with bench__ and add them to bench/bench.h, so that we can
share those on the tools needing to access those variables from signal
handlers.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200303155811.GD13702@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 #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
 
 
 static unsigned int nthreads = 0;
 static unsigned int nsecs    = 8;
-struct timeval start, end, runtime;
 static bool done, __verbose, randomize;
 
 /*
 {
        /* 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 nest_epollfd(void)
 
        threads_starting = nthreads;
 
-       gettimeofday(&start, NULL);
+       gettimeofday(&bench__start, NULL);
 
        do_threads(worker, cpu);
 
 
 
 static unsigned int nthreads = 0;
 static unsigned int nsecs    = 8;
-struct timeval start, end, runtime;
 static bool wdone, done, __verbose, randomize, nonblocking;
 
 /*
 {
        /* 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)
 
        printf("\nAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n",
               avg, rel_stddev_stats(stddev, avg),
-              (int) runtime.tv_sec);
+              (int)bench__runtime.tv_sec);
 }
 
 static int do_threads(struct worker *worker, struct perf_cpu_map *cpu)
 
        threads_starting = nthreads;
 
-       gettimeofday(&start, NULL);
+       gettimeofday(&bench__start, NULL);
 
        do_threads(worker, cpu);
 
                qsort(worker, nthreads, sizeof(struct worker), cmpworker);
 
        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);
 
 
 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;
 {
        /* 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)
 
        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)
 
        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));
        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)
 
 static bool done = false, fshared = false;
 static unsigned int 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;
 
        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,
 {
        /* 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)
 
        threads_starting = nthreads;
        pthread_attr_init(&thread_attr);
-       gettimeofday(&start, NULL);
+       gettimeofday(&bench__start, NULL);
 
        create_threads(worker, thread_attr, cpu);
        pthread_attr_destroy(&thread_attr);
        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)