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

[Christophe Leroy]

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

Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
 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