This is a note to let you know that I've just added the patch titled
selftests/powerpc: Fix argument order to timer_sub()
to the 6.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-powerpc-fix-argument-order-to-timer_sub.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 181f3f44431d7d91137e9ae1c9a0d088b8b6d1ea
Author: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Date: Wed Dec 18 22:43:47 2024 +1100
selftests/powerpc: Fix argument order to timer_sub()
[ Upstream commit 2bf66e66d2e6feece6175ec09ec590a0a8563bdd ]
Commit c814bf958926 ("powerpc/selftests: Use timersub() for
gettimeofday()"), got the order of arguments to timersub() wrong,
leading to a negative time delta being reported, eg:
test: gettimeofday
tags: git_version:v6.12-rc5-409-gdddf291c3030
time = -3.297781
success: gettimeofday
The correct order is minuend, subtrahend, which in this case is end,
start. Which gives:
test: gettimeofday
tags: git_version:v6.12-rc5-409-gdddf291c3030-dirty
time = 3.300650
success: gettimeofday
Fixes: c814bf958926 ("powerpc/selftests: Use timersub() for gettimeofday()")
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
Link: https://patch.msgid.link/20241218114347.428108-1-mpe@xxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/testing/selftests/powerpc/benchmarks/gettimeofday.c b/tools/testing/selftests/powerpc/benchmarks/gettimeofday.c
index 580fcac0a09f3..b71ef8a493ed1 100644
--- a/tools/testing/selftests/powerpc/benchmarks/gettimeofday.c
+++ b/tools/testing/selftests/powerpc/benchmarks/gettimeofday.c
@@ -20,7 +20,7 @@ static int test_gettimeofday(void)
gettimeofday(&tv_end, NULL);
}
- timersub(&tv_start, &tv_end, &tv_diff);
+ timersub(&tv_end, &tv_start, &tv_diff);
printf("time = %.6f\n", tv_diff.tv_sec + (tv_diff.tv_usec) * 1e-6);
