diff --git a/tools/testing/selftests/zram/zram01.sh b/tools/testing/selftests/zram/zram01.sh
index 114863d9fb876..e9e9eb777e2c7 100755
--- a/tools/testing/selftests/zram/zram01.sh
+++ b/tools/testing/selftests/zram/zram01.sh
@@ -33,8 +33,6 @@ zram_algs="lzo"
 
 zram_fill_fs()
 {
-	local mem_free0=$(free -m | awk 'NR==2 {print $4}')
-
 	for i in $(seq 0 $(($dev_num - 1))); do
 		echo "fill zram$i..."
 		local b=0
@@ -45,29 +43,17 @@ zram_fill_fs()
 			b=$(($b + 1))
 		done
 		echo "zram$i can be filled with '$b' KB"
-	done
 
-	local mem_free1=$(free -m | awk 'NR==2 {print $4}')
-	local used_mem=$(($mem_free0 - $mem_free1))
+		local mem_used_total=`awk '{print $3}' "/sys/block/zram$i/mm_stat"`
+		local v=$((100 * 1024 * $b / $mem_used_total))
+		if [ "$v" -lt 100 ]; then
+			 echo "FAIL compression ratio: 0.$v:1"
+			 ERR_CODE=-1
+			 return
+		fi
 
-	local total_size=0
-	for sm in $zram_sizes; do
-		local s=$(echo $sm | sed 's/M//')
-		total_size=$(($total_size + $s))
+		echo "zram compression ratio: $(echo "scale=2; $v / 100 " | bc):1: OK"
 	done
-
-	echo "zram used ${used_mem}M, zram disk sizes ${total_size}M"
-
-	local v=$((100 * $total_size / $used_mem))
-
-	if [ "$v" -lt 100 ]; then
-		echo "FAIL compression ratio: 0.$v:1"
-		ERR_CODE=-1
-		zram_cleanup
-		return
-	fi
-
-	echo "zram compression ratio: $(echo "scale=2; $v / 100 " | bc):1: OK"
 }
 
 check_prereqs