perf bench syscall: Add execve syscall benchmark

This commit adds the execve syscall benchmark, more syscall benchmarks
can be added in the future.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/1668052208-14047-5-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 37 insertions, 0 deletions

diff --git a/tools/perf/bench/bench.h b/tools/perf/bench/bench.h
index 0c58448273da..e43893151a3e 100644
--- a/tools/perf/bench/bench.h
+++ b/tools/perf/bench/bench.h
@@ -23,6 +23,7 @@ int bench_sched_messaging(int argc, const char **argv);
 int bench_sched_pipe(int argc, const char **argv);
 int bench_syscall_basic(int argc, const char **argv);
 int bench_syscall_getpgid(int argc, const char **argv);
+int bench_syscall_execve(int argc, const char **argv);
 int bench_mem_memcpy(int argc, const char **argv);
 int bench_mem_memset(int argc, const char **argv);
 int bench_mem_find_bit(int argc, const char **argv);
diff --git a/tools/perf/bench/syscall.c b/tools/perf/bench/syscall.c
index 6411b146ba68..fe79f7f3091e 100644
--- a/tools/perf/bench/syscall.c
+++ b/tools/perf/bench/syscall.c
@@ -14,6 +14,7 @@
 #include <sys/time.h>
 #include <sys/syscall.h>
 #include <sys/types.h>
+#include <sys/wait.h>
 #include <unistd.h>
 #include <stdlib.h>
 
@@ -30,6 +31,27 @@ static const char * const bench_syscall_usage[] = {
 	NULL
 };
 
+static void test_execve(void)
+{
+	const char *pathname = "/bin/true";
+	char *const argv[] = { (char *)pathname, NULL };
+	pid_t pid = fork();
+
+	if (pid < 0) {
+		fprintf(stderr, "fork failed\n");
+		exit(1);
+	} else if (pid == 0) {
+		execve(pathname, argv, NULL);
+		fprintf(stderr, "execve /bin/true failed\n");
+		exit(1);
+	} else {
+		if (waitpid(pid, NULL, 0) < 0) {
+			fprintf(stderr, "waitpid failed\n");
+			exit(1);
+		}
+	}
+}
+
 static int bench_syscall_common(int argc, const char **argv, int syscall)
 {
 	struct timeval start, stop, diff;
@@ -49,6 +71,12 @@ static int bench_syscall_common(int argc, const char **argv, int syscall)
 		case __NR_getpgid:
 			getpgid(0);
 			break;
+		case __NR_execve:
+			test_execve();
+			/* Only loop 10000 times to save time */
+			if (i == 10000)
+				loops = 10000;
+			break;
 		default:
 			break;
 		}
@@ -64,6 +92,9 @@ static int bench_syscall_common(int argc, const char **argv, int syscall)
 	case __NR_getpgid:
 		name = "getpgid()";
 		break;
+	case __NR_execve:
+		name = "execve()";
+		break;
 	default:
 		break;
 	}
@@ -111,3 +142,8 @@ int bench_syscall_getpgid(int argc, const char **argv)
 {
 	return bench_syscall_common(argc, argv, __NR_getpgid);
 }
+
+int bench_syscall_execve(int argc, const char **argv)
+{
+	return bench_syscall_common(argc, argv, __NR_execve);
+}