Re: Possible bug - LTP failure for memcg

[Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>]

On Thu 14-05-15 16:44:20, Cyril Hrubis wrote:
> Hi!
> > Signed-off-by: Michal Hocko <miso-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
> 
>                                  ^
> 			       forgotten git config user.email?

Dohh...

> > ---
> >  testcases/kernel/controllers/memcg/functional/memcg_function_test.sh | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh b/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
> > index cfc75fa730df..399c5614468a 100755
> > --- a/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
> > +++ b/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
> > @@ -211,8 +211,8 @@ testcase_29()
> >  	echo $pid > tasks
> >  	kill -s USR1 $pid 2> /dev/null
> >  	sleep 1
> > -	echo $pid > ../tasks
> 
> This change breaks the testcase on older kernels:

Yeah, my bad, I've started with this then changed it back but forgot to
add it to the commit. Sorry about that. Hopefully the correct one:
---
From 90a487d96fe09763b4517314797e2db32ce232b4 Mon Sep 17 00:00:00 2001
From: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>
Date: Thu, 14 May 2015 16:24:38 +0200
Subject: [PATCH] controllers/memcg: fix force_empty

testcase_29 and testcase_30 are no longer testing anything because
the kernel allows to use force_empty even for memcgs with active
tasks since f61c42a7d911 ("memcg: remove tasks/children test from
mem_cgroup_force_empty()) kernel commit.

If we really want to test this functionality then just expect the
success for regular mmap and expect the failure when the charged
memory is mlocked.

Signed-off-by: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>
---
 testcases/kernel/controllers/memcg/functional/memcg_function_test.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh b/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
index cfc75fa730df..f55593996b86 100755
--- a/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
+++ b/testcases/kernel/controllers/memcg/functional/memcg_function_test.sh
@@ -213,6 +213,7 @@ testcase_29()
 	sleep 1
 	echo $pid > ../tasks
 
+	# This expects that there is swap configured
 	echo 1 > memory.force_empty
 	if [ $? -eq 0 ]; then
 		result $PASS "force memory succeeded"
@@ -225,7 +226,7 @@ testcase_29()
 
 testcase_30()
 {
-	$TEST_PATH/memcg_process --mmap-anon -s $PAGESIZE &
+	$TEST_PATH/memcg_process --mmap-lock2 -s $PAGESIZE &
 	pid=$!
 	sleep 1
 	echo $pid > tasks
-- 
2.1.4

-- 
Michal Hocko
SUSE Labs