perf bench futex: Sanitize numeric parameters

This gets rid of oddities such as:

  perf bench futex hash -t -4
  perf: calloc: Cannot allocate memory

Runtime (and many more) are equally busted, i.e. run for bogus amounts of
time. Just use the abs, instead of, for example errorring out.

Committer note:

After the patch:

  $ perf bench futex hash -t -4
  # Running 'futex/hash' benchmark:
  Run summary [PID 10178]: 4 threads, each operating on 1024 [private] futexes for 10 secs.

  [thread  0] futexes: 0x34f9fa0 ... 0x34faf9c [ 4702208 ops/sec ]
  [thread  1] futexes: 0x34fb140 ... 0x34fc13c [ 4707020 ops/sec ]
  [thread  2] futexes: 0x34fc2e0 ... 0x34fd2dc [ 4711526 ops/sec ]
  [thread  3] futexes: 0x34fd480 ... 0x34fe47c [ 4709683 ops/sec ]

  Averaged 4707609 operations/sec (+- 0.04%), total secs = 10
  $

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1477342613-9938-3-git-send-email-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/bench/futex-hash.c

@@ -130,6 +130,8 @@ int bench_futex_hash(int argc, const char **argv,
 	}
 
 	ncpus = sysconf(_SC_NPROCESSORS_ONLN);
+	nsecs = futexbench_sanitize_numeric(nsecs);
+	nfutexes = futexbench_sanitize_numeric(nfutexes);
 
 	sigfillset(&act.sa_mask);
 	act.sa_sigaction = toggle_done;
@@ -137,6 +139,8 @@ int bench_futex_hash(int argc, const char **argv,
 
 	if (!nthreads) /* default to the number of CPUs */
 		nthreads = ncpus;
+	else
+		nthreads = futexbench_sanitize_numeric(nthreads);
 
 	worker = calloc(nthreads, sizeof(*worker));
 	if (!worker)

tools/perf/bench/futex-lock-pi.c

@@ -152,6 +152,7 @@ int bench_futex_lock_pi(int argc, const char **argv,
 		goto err;
 
 	ncpus = sysconf(_SC_NPROCESSORS_ONLN);
+	nsecs = futexbench_sanitize_numeric(nsecs);
 
 	sigfillset(&act.sa_mask);
 	act.sa_sigaction = toggle_done;
@@ -159,6 +160,8 @@ int bench_futex_lock_pi(int argc, const char **argv,
 
 	if (!nthreads)
 		nthreads = ncpus;
+	else
+		nthreads = futexbench_sanitize_numeric(nthreads);
 
 	worker = calloc(nthreads, sizeof(*worker));
 	if (!worker)

tools/perf/bench/futex-requeue.c

@@ -128,6 +128,8 @@ int bench_futex_requeue(int argc, const char **argv,
 
 	if (!nthreads)
 		nthreads = ncpus;
+	else
+		nthreads = futexbench_sanitize_numeric(nthreads);
 
 	worker = calloc(nthreads, sizeof(*worker));
 	if (!worker)

tools/perf/bench/futex-wake-parallel.c

@@ -217,8 +217,12 @@ int bench_futex_wake_parallel(int argc, const char **argv,
 	sigaction(SIGINT, &act, NULL);
 
 	ncpus = sysconf(_SC_NPROCESSORS_ONLN);
+	nwaking_threads = futexbench_sanitize_numeric(nwaking_threads);
+
 	if (!nblocked_threads)
 		nblocked_threads = ncpus;
+	else
+		nblocked_threads = futexbench_sanitize_numeric(nblocked_threads);
 
 	/* some sanity checks */
 	if (nwaking_threads > nblocked_threads || !nwaking_threads)

tools/perf/bench/futex-wake.c

@@ -129,6 +129,7 @@ int bench_futex_wake(int argc, const char **argv,
 	}
 
 	ncpus = sysconf(_SC_NPROCESSORS_ONLN);
+	nwakes = futexbench_sanitize_numeric(nwakes);
 
 	sigfillset(&act.sa_mask);
 	act.sa_sigaction = toggle_done;
@@ -136,6 +137,8 @@ int bench_futex_wake(int argc, const char **argv,
 
 	if (!nthreads)
 		nthreads = ncpus;
+	else
+		nthreads = futexbench_sanitize_numeric(nthreads);
 
 	worker = calloc(nthreads, sizeof(*worker));
 	if (!worker)

tools/perf/bench/futex.h

@@ -7,6 +7,7 @@
 #ifndef _FUTEX_H
 #define _FUTEX_H
 
+#include <stdlib.h>
 #include <unistd.h>
 #include <sys/syscall.h>
 #include <sys/types.h>
@@ -99,4 +100,7 @@ static inline int pthread_attr_setaffinity_np(pthread_attr_t *attr,
 }
 #endif
 
+/* User input sanitation */
+#define futexbench_sanitize_numeric(__n) abs((__n))
+
 #endif /* _FUTEX_H */