From: Waiman Long <longman@xxxxxxxxxx> Subject: selftests/vm: make charge_reserved_hugetlb.sh work with existing cgroup setting The hugetlb cgroup reservation test charge_reserved_hugetlb.sh assume that no cgroup filesystems are mounted before running the test. That is not true in many cases. As a result, the test fails to run. Fix that by querying the current cgroup mount setting and using the existing cgroup setup instead before attempting to freshly mount a cgroup filesystem. Similar change is also made for hugetlb_reparenting_test.sh as well, though it still has problem if cgroup v2 isn't used. The patched test scripts were run on a centos 8 based system to verify that they ran properly. Link: https://lkml.kernel.org/r/20220106201359.1646575-1-longman@xxxxxxxxxx Fixes: 29750f71a9b4 ("hugetlb_cgroup: add hugetlb_cgroup reservation tests") Signed-off-by: Waiman Long <longman@xxxxxxxxxx> Acked-by: Mina Almasry <almasrymina@xxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/charge_reserved_hugetlb.sh | 34 +++++----- tools/testing/selftests/vm/hugetlb_reparenting_test.sh | 21 +++--- tools/testing/selftests/vm/write_hugetlb_memory.sh | 2 3 files changed, 34 insertions(+), 23 deletions(-) --- a/tools/testing/selftests/vm/charge_reserved_hugetlb.sh~selftests-vm-make-charge_reserved_hugetlbsh-work-with-existing-cgroup-setting +++ a/tools/testing/selftests/vm/charge_reserved_hugetlb.sh @@ -24,19 +24,23 @@ if [[ "$1" == "-cgroup-v2" ]]; then reservation_usage_file=rsvd.current fi -cgroup_path=/dev/cgroup/memory -if [[ ! -e $cgroup_path ]]; then - mkdir -p $cgroup_path - if [[ $cgroup2 ]]; then +if [[ $cgroup2 ]]; then + cgroup_path=$(mount -t cgroup2 | head -1 | awk -e '{print $3}') + if [[ -z "$cgroup_path" ]]; then + cgroup_path=/dev/cgroup/memory mount -t cgroup2 none $cgroup_path - else + do_umount=1 + fi + echo "+hugetlb" >$cgroup_path/cgroup.subtree_control +else + cgroup_path=$(mount -t cgroup | grep ",hugetlb" | awk -e '{print $3}') + if [[ -z "$cgroup_path" ]]; then + cgroup_path=/dev/cgroup/memory mount -t cgroup memory,hugetlb $cgroup_path + do_umount=1 fi fi - -if [[ $cgroup2 ]]; then - echo "+hugetlb" >/dev/cgroup/memory/cgroup.subtree_control -fi +export cgroup_path function cleanup() { if [[ $cgroup2 ]]; then @@ -108,7 +112,7 @@ function setup_cgroup() { function wait_for_hugetlb_memory_to_get_depleted() { local cgroup="$1" - local path="/dev/cgroup/memory/$cgroup/hugetlb.${MB}MB.$reservation_usage_file" + local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$reservation_usage_file" # Wait for hugetlbfs memory to get depleted. while [ $(cat $path) != 0 ]; do echo Waiting for hugetlb memory to get depleted. @@ -121,7 +125,7 @@ function wait_for_hugetlb_memory_to_get_ local cgroup="$1" local size="$2" - local path="/dev/cgroup/memory/$cgroup/hugetlb.${MB}MB.$reservation_usage_file" + local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$reservation_usage_file" # Wait for hugetlbfs memory to get written. while [ $(cat $path) != $size ]; do echo Waiting for hugetlb memory reservation to reach size $size. @@ -134,7 +138,7 @@ function wait_for_hugetlb_memory_to_get_ local cgroup="$1" local size="$2" - local path="/dev/cgroup/memory/$cgroup/hugetlb.${MB}MB.$fault_usage_file" + local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$fault_usage_file" # Wait for hugetlbfs memory to get written. while [ $(cat $path) != $size ]; do echo Waiting for hugetlb memory to reach size $size. @@ -574,5 +578,7 @@ for populate in "" "-o"; do done # populate done # method -umount $cgroup_path -rmdir $cgroup_path +if [[ $do_umount ]]; then + umount $cgroup_path + rmdir $cgroup_path +fi --- a/tools/testing/selftests/vm/hugetlb_reparenting_test.sh~selftests-vm-make-charge_reserved_hugetlbsh-work-with-existing-cgroup-setting +++ a/tools/testing/selftests/vm/hugetlb_reparenting_test.sh @@ -18,19 +18,24 @@ if [[ "$1" == "-cgroup-v2" ]]; then usage_file=current fi -CGROUP_ROOT='/dev/cgroup/memory' -MNT='/mnt/huge/' -if [[ ! -e $CGROUP_ROOT ]]; then - mkdir -p $CGROUP_ROOT - if [[ $cgroup2 ]]; then +if [[ $cgroup2 ]]; then + CGROUP_ROOT=$(mount -t cgroup2 | head -1 | awk -e '{print $3}') + if [[ -z "$CGROUP_ROOT" ]]; then + CGROUP_ROOT=/dev/cgroup/memory mount -t cgroup2 none $CGROUP_ROOT - sleep 1 - echo "+hugetlb +memory" >$CGROUP_ROOT/cgroup.subtree_control - else + do_umount=1 + fi + echo "+hugetlb +memory" >$CGROUP_ROOT/cgroup.subtree_control +else + CGROUP_ROOT=$(mount -t cgroup | grep ",hugetlb" | awk -e '{print $3}') + if [[ -z "$CGROUP_ROOT" ]]; then + CGROUP_ROOT=/dev/cgroup/memory mount -t cgroup memory,hugetlb $CGROUP_ROOT + do_umount=1 fi fi +MNT='/mnt/huge/' function get_machine_hugepage_size() { hpz=$(grep -i hugepagesize /proc/meminfo) --- a/tools/testing/selftests/vm/write_hugetlb_memory.sh~selftests-vm-make-charge_reserved_hugetlbsh-work-with-existing-cgroup-setting +++ a/tools/testing/selftests/vm/write_hugetlb_memory.sh @@ -14,7 +14,7 @@ want_sleep=$8 reserve=$9 echo "Putting task in cgroup '$cgroup'" -echo $$ > /dev/cgroup/memory/"$cgroup"/cgroup.procs +echo $$ > ${cgroup_path:-/dev/cgroup/memory}/"$cgroup"/cgroup.procs echo "Method is $method" _