2021-06-04 12:34:07

by Christophe Leroy

Subject: [PATCH] powerpc/selftests: Use gettid() instead of getppid() for null_syscall

gettid() is 10% lighter than getppid(), use it for null_syscall selftest.

Signed-off-by: Christophe Leroy <[email protected]>
---
tools/testing/selftests/powerpc/benchmarks/null_syscall.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/powerpc/benchmarks/null_syscall.c b/tools/testing/selftests/powerpc/benchmarks/null_syscall.c
index 579f0215c6e7..9836838a529f 100644
--- a/tools/testing/selftests/powerpc/benchmarks/null_syscall.c
+++ b/tools/testing/selftests/powerpc/benchmarks/null_syscall.c
@@ -14,6 +14,7 @@
#include <time.h>
#include <sys/types.h>
#include <sys/time.h>
+#include <sys/syscall.h>
#include <signal.h>

static volatile int soak_done;
@@ -121,7 +122,7 @@ static void do_null_syscall(unsigned long nr)
unsigned long i;

for (i = 0; i < nr; i++)
- getppid();
+ syscall(__NR_gettid);
}

#define TIME(A, STR) \
--
2.25.0

2021-06-18 06:18:56

by Michael Ellerman

Subject: Re: [PATCH] powerpc/selftests: Use gettid() instead of getppid() for null_syscall

On Fri, 4 Jun 2021 12:31:09 +0000 (UTC), Christophe Leroy wrote:
> gettid() is 10% lighter than getppid(), use it for null_syscall selftest.

Applied to powerpc/next.

[1/1] powerpc/selftests: Use gettid() instead of getppid() for null_syscall
https://git.kernel.org/powerpc/c/a1ea0ca8a6f17d7b79bbc4d05dd4e6ca162d8f15

cheers