[LTP] [PATCH V2 3/4] memcg_stress_test.sh: rewrite

[Stanislav Kholmanskikh]

 * Use the LTP API for shell test cases

 * Verify command exit codes by using ROD

 * Now we send the termination signal to all the processes,
   and only then we do 'wait'. With this scheme SIGINT
   does not make the test execute for "much longer time",
   so the SIGKILL workaround implemented in 9b9a6bb10258bc
   is not required anymore.

Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com>
---
Changes since V1:
 * ./memcg_process_stress -> memcg_process_stress
 * /bin/kill -s SIGNAL -> kill -s NAL
 * use only awk to parse for mem_free and swap_free
 * changed the comment string after [ "$mem" -gt 0 ] ||

 .../controllers/memcg/stress/memcg_stress_test.sh  |  110 +++++++++++++-------
 1 files changed, 71 insertions(+), 39 deletions(-)

diff --git a/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh b/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
index dc610f1..ad2fb03 100755
--- a/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
+++ b/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
@@ -1,4 +1,4 @@
-#! /bin/sh
+#!/bin/sh
 
 ################################################################################
 ##                                                                            ##
@@ -25,37 +25,57 @@
 ##                                                                            ##
 ################################################################################
 
-cd $LTPROOT/testcases/bin
-export TCID="memcg_stress_test"
-export TST_TOTAL=2
-export TST_COUNT=0
+TCID=memcg_stress_test
+TST_TOTAL=2
+. test.sh
 
 if [ "x$(grep -w memory /proc/cgroups | cut -f4)" != "x1" ]; then
-        echo "WARNING:";
-        echo "Either Kernel does not support for memory resource controller or feature not enabled";
-        echo "Skipping all memcgroup testcases....";
-        exit 0
+	tst_brkm TCONF "Kernel does not support the memory resource controller"
 fi
 
 RUN_TIME=$(( 60 * 60 ))
 
+children=""
+nr_children=0
+memcg_path=/dev/memcg
+memcg_created=0
+
 cleanup()
 {
-	if [ -e /dev/memcg ]; then
-		umount /dev/memcg 2>/dev/null
-		rmdir /dev/memcg 2>/dev/null
+	for child in $children; do
+		kill -s KILL $child 2> /dev/null
+	done
+	wait
+
+	if [ "$memcg_created" -ne 0 ]; then
+		for i in $(seq 0 $(( $nr_children - 1 ))); do
+			rmdir "$memcg_path/$i" 2> /dev/null
+		done
+		umount "$memcg_path"
+		rmdir "$memcg_path"
 	fi
 }
+TST_CLEANUP=cleanup
 
+do_unmount()
+{
+	ROD umount "$memcg_path"
+	ROD rmdir "$memcg_path"
+	memcg_created=0
+}
 
 do_mount()
 {
-	cleanup;
-
-	mkdir /dev/memcg 2> /dev/null
-	mount -t cgroup -omemory memcg /dev/memcg
+	ROD mkdir "$memcg_path"
+	memcg_created=1
+	ROD mount -t cgroup -omemory memcg "$memcg_path"
 }
 
+is_int()
+{
+	[ "$1" -eq "$1" ] 2> /dev/null
+	return $?
+}
 
 # Run the stress test
 #
@@ -65,33 +85,41 @@ do_mount()
 # $4 - How long does this test run ? in second
 run_stress()
 {
-	do_mount;
+	nr_children=0
+	children=""
+
+	do_mount
 
-	for i in $(seq 0 $(($1-1)))
-	do
-		mkdir /dev/memcg/$i 2> /dev/null
-		./memcg_process_stress $2 $3 &
-		eval pid$i=$!
+	for i in $(seq 0 $(( $1 - 1 ))); do
+		ROD mkdir "$memcg_path/$i"
+		memcg_process_stress $2 $3 &
+		child=$!
 
-		eval echo \$pid$i > /dev/memcg/$i/tasks
+		nr_children=$(( $nr_children + 1 ))
+		children="$children $child"
+
+		ROD echo $child \> "$memcg_path/$i/tasks"
 	done
 
-	for i in $(seq 0 $(($1-1)))
-	do
-		eval /bin/kill -s SIGUSR1 \$pid$i 2> /dev/null
+	for child in $children; do
+		ROD kill -s USR1 $child
 	done
 
 	sleep $4
 
-	for i in $(seq 0 $(($1-1)))
-	do
-		eval /bin/kill -s SIGKILL \$pid$i 2> /dev/null
-		eval wait \$pid$i
+	for child in $children; do
+		ROD kill -s INT $child
+	done
+
+	for child in $children; do
+		ROD wait $child
+	done
 
-		rmdir /dev/memcg/$i 2> /dev/null
+	for i in $(seq 0 $(( $nr_children - 1 ))); do
+		ROD rmdir "$memcg_path/$i"
 	done
 
-	cleanup;
+	do_unmount
 }
 
 testcase_1()
@@ -108,19 +136,23 @@ testcase_2()
 	tst_resm TPASS "stress test 2 passed"
 }
 
-echo 3 > /proc/sys/vm/drop_caches
+ROD echo 3 \> /proc/sys/vm/drop_caches
 sleep 2
-mem_free=`cat /proc/meminfo | grep MemFree | awk '{ print $2 }'`
-swap_free=`cat /proc/meminfo | grep SwapFree | awk '{ print $2 }'`
+
+mem_free=$(awk '/MemFree/ {print $2}' /proc/meminfo)
+is_int "$mem_free" || tst_brkm TBROK "Unable to determine mem_free"
+
+swap_free=$(awk '/SwapFree/ {print $2}' /proc/meminfo)
+is_int "$swap_free" || tst_brkm TBROK "Unable to determine swap_free"
 
 mem=$(( $mem_free + $swap_free / 2 ))
-mem=$(( mem / 1024 ))
+mem=$(( $mem / 1024 ))
+[ "$mem" -gt 0 ] || tst_brkm TBROK "mem is not positive: $mem"
 
 date
-export TST_COUNT=$(( $TST_COUNT + 1 ))
 testcase_1
-export TST_COUNT=$(( $TST_COUNT + 1 ))
+date
 testcase_2
 date
 
-exit 0
+tst_exit
-- 
1.7.1