[PATCH AUTOSEL 5.10 06/27] selftests/zram: Skip max_comp_streams interface on newer kernel

Sasha Levin
2022-02-09T18:41:37Z

From: Yang Xu <xuyang2018.jy@fujitsu.com>

[ Upstream commit fc4eb486a59d70bd35cf1209f0e68c2d8b979193 ]

Since commit 43209ea2d17a ("zram: remove max_comp_streams internals"), zram
has switched to per-cpu streams. Even kernel still keep this interface for
some reasons, but writing to max_comp_stream doesn't take any effect. So
skip it on newer kernel ie 4.7.

The code that comparing kernel version is from xfstests testsuite ext4/053.

Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/testing/selftests/zram/zram_lib.sh | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/tools/testing/selftests/zram/zram_lib.sh b/tools/testing/selftests/zram/zram_lib.sh
index 6f872f266fd11..f47fc0f27e99e 100755
--- a/tools/testing/selftests/zram/zram_lib.sh
+++ b/tools/testing/selftests/zram/zram_lib.sh
@@ -11,6 +11,9 @@ dev_mounted=-1

# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
+kernel_version=`uname -r | cut -d'.' -f1,2`
+kernel_major=${kernel_version%.*}
+kernel_minor=${kernel_version#*.}

trap INT

@@ -25,6 +28,20 @@ check_prereqs()
fi
}

+kernel_gte()
+{
+ major=${1%.*}
+ minor=${1#*.}
+
+ if [ $kernel_major -gt $major ]; then
+ return 0
+ elif [[ $kernel_major -eq $major && $kernel_minor -ge $minor ]]; then
+ return 0
+ fi
+
+ return 1
+}
+
zram_cleanup()
{
echo "zram cleanup"
@@ -86,6 +103,13 @@ zram_max_streams()
{
echo "set max_comp_streams to zram device(s)"

+ kernel_gte 4.7
+ if [ $? -eq 0 ]; then
+ echo "The device attribute max_comp_streams was"\
+ "deprecated in 4.7"
+ return 0
+ fi
+
local i=0
for max_s in $zram_max_streams; do
local sys_path="/sys/block/zram${i}/max_comp_streams"
--
2.34.1