[LTP] [PATCH V3 4/4] memcg/functional: check several times if the process is killed

[Stanislav Kholmanskikh]

On some systems it may take slightly more than one second
to kill the memcg_process. So let's check several times if the
process is alive.

Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com>
---
Changes since [1]:
 * 'sleep 1' next to memcg_process & is substituted by patch 3
   of the series
 * use /proc/pid and /proc/pid/status to check wheter the process
   exists and if it exists whether it's in Z state


[1] http://lists.linux.it/pipermail/ltp/2016-May/001840.html


 .../controllers/memcg/functional/memcg_lib.sh      |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/testcases/kernel/controllers/memcg/functional/memcg_lib.sh b/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
index b191ea6..46bad42 100755
--- a/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
+++ b/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
@@ -251,10 +251,19 @@ test_proc_kill()
 	echo $pid > tasks
 
 	kill -s USR1 $pid 2> /dev/null
-	sleep 1
 
-	ps -p $pid > /dev/null 2> /dev/null
-	if [ $? -ne 0 ]; then
+	tpk_pid_exists=1
+	for tpk_iter in $(seq 20); do
+		if [ ! -d "/proc/$pid" ] ||
+			grep -q 'Z (zombie)' "/proc/$pid/status"; then
+			tpk_pid_exists=0
+			break
+		fi
+
+		tst_sleep 250ms
+	done
+
+	if [ $tpk_pid_exists -eq 0 ]; then
 		wait $pid
 		ret=$?
 		if [ $ret -eq 1 ]; then
-- 
1.7.1