perf bench syscall: Introduce bench_syscall_common()

In the current code, there is only a basic syscall benchmark via
getppid, this is not enough. Introduce bench_syscall_common() so that we
can add more syscalls to benchmark.

This is preparation for later patch, no functionality change.
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/1668052208-14047-3-git-send-email-yangtiezhu@loongson.cnSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/arch/x86/include/uapi/asm/unistd_32.h

 /* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NR_getppid
+#define __NR_getppid 64
+#endif
 #ifndef __NR_gettid
 #define __NR_gettid 224
 #endif

tools/arch/x86/include/uapi/asm/unistd_64.h

 /* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NR_getppid
+#define __NR_getppid 110
+#endif
 #ifndef __NR_gettid
 #define __NR_gettid 186
 #endif

tools/perf/bench/syscall.c

@@ -30,25 +30,41 @@ static const char * const bench_syscall_usage[] = {
 	NULL
 };
 
-int bench_syscall_basic(int argc, const char **argv)
+static int bench_syscall_common(int argc, const char **argv, int syscall)
 {
 	struct timeval start, stop, diff;
 	unsigned long long result_usec = 0;
+	const char *name = NULL;
 	int i;
 
 	argc = parse_options(argc, argv, options, bench_syscall_usage, 0);
 
 	gettimeofday(&start, NULL);
 
-	for (i = 0; i < loops; i++)
+	for (i = 0; i < loops; i++) {
+		switch (syscall) {
+		case __NR_getppid:
 			getppid();
+			break;
+		default:
+			break;
+		}
+	}
 
 	gettimeofday(&stop, NULL);
 	timersub(&stop, &start, &diff);
 
+	switch (syscall) {
+	case __NR_getppid:
+		name = "getppid()";
+		break;
+	default:
+		break;
+	}
+
 	switch (bench_format) {
 	case BENCH_FORMAT_DEFAULT:
-		printf("# Executed %'d getppid() calls\n", loops);
+		printf("# Executed %'d %s calls\n", loops, name);
 
 		result_usec = diff.tv_sec * 1000000;
 		result_usec += diff.tv_usec;
@@ -79,3 +95,8 @@ int bench_syscall_basic(int argc, const char **argv)
 
 	return 0;
 }
+
+int bench_syscall_basic(int argc, const char **argv)
+{
+	return bench_syscall_common(argc, argv, __NR_getppid);
+}