alloc_pagecache_max_30M() in the cgroup memcg tests performs a 50MB
pagecache allocation, which it expects to be capped at 30MB due to the
calling process having a memory.high setting of 30MB. After the
allocation, the function contains a check that verifies that MB(29) <
memory.current <= MB(30). This check can actually fail
non-deterministically.
The testcases that use this function are test_memcg_high() and
test_memcg_max(), which set memory.min and memory.max to 30MB respectively
for the cgroup under test. The allocation can slightly exceed this number
in both cases, and for memory.max, the process performing the allocation
will not have the OOM killer invoked as it's performing a pagecache
allocation. This patchset therefore updates the above check to instead
use the verify_close() helper function.
Link: https://lkml.kernel.org/r/20220423155619.3669555-6-void@manifault.com
Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
test_memcg_sock() in the cgroup memcg tests, verifies expected memory
accounting for sockets. The test forks a process which functions as a TCP
server, and sends large buffers back and forth between itself (as the TCP
client) and the forked TCP server. While doing so, it verifies that
memory.current and memory.stat.sock look correct.
There is currently a check in tcp_client() which asserts memory.current >=
memory.stat.sock. This check is racy, as between memory.current and
memory.stat.sock being queried, a packet could come in which causes
mem_cgroup_charge_skmem() to be invoked. This could cause
memory.stat.sock to exceed memory.current. Reversing the order of
querying doesn't address the problem either, as memory may be reclaimed
between the two calls. Instead, this patch just removes that assertion
altogether, and instead relies on the values_close() check that follows to
validate the expected accounting.
Link: https://lkml.kernel.org/r/20220423155619.3669555-5-void@manifault.com
Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The test_memcg_oom_group_leaf_events() testcase in the cgroup memcg tests
validates that processes in a group that perform allocations exceeding
memory.oom.group are killed. It also validates that the
memory.events.oom_kill events are properly propagated in this case.
Commit 06e11c907ea4 ("kselftests: memcg: update the oom group leaf events
test") fixed test_memcg_oom_group_leaf_events() to account for the fact
that the memory.events.oom_kill events in a child cgroup is propagated up
to its parent. This behavior can actually be configured by the
memory_localevents mount option, so this patch updates the testcase to
properly account for the possible presence of this mount option.
Link: https://lkml.kernel.org/r/20220423155619.3669555-4-void@manifault.com
Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The test_memcg_low() testcase in test_memcontrol.c verifies the expected
behavior of groups using the memory.low knob. Part of the testcase
verifies that a group with memory.low that experiences reclaim due to
memory pressure elsewhere in the system, observes memory.events.low events
as a result of that reclaim.
In commit 8a931f8013 ("mm: memcontrol: recursive memory.low
protection"), the memory controller was updated to propagate memory.low
and memory.min protection from a parent group to its children via a
configurable memory_recursiveprot mount option. This unfortunately broke
the memcg tests, which asserts that a sibling that experienced reclaim but
had a memory.low value of 0, would not observe any memory.low events.
This patch updates test_memcg_low() to account for the new behavior
introduced by memory_recursiveprot.
So as to make the test resilient to multiple configurations, the patch
also adds a new proc_mount_contains() helper that checks for a string in
/proc/mounts, and is used to toggle behavior based on whether the default
memory_recursiveprot was present.
Link: https://lkml.kernel.org/r/20220423155619.3669555-3-void@manifault.com
Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Fix bugs in memcontroller cgroup tests", v2.
tools/testing/selftests/cgroup/test_memcontrol.c contains a set of
testcases which validate expected behavior of the cgroup memory
controller. Roman Gushchin recently sent out a patchset that fixed a few
issues in the test. This patchset continues that effort by fixing a few
more issues that were causing non-deterministic failures in the suite.
With this patchset, I'm unable to reproduce any more errors after running
the tests in a continuous loop for many iterations. Before, I was able to
reproduce at least one of the errors fixed in this patchset with just one
or two runs.
This patch (of 5):
In test_memcg_min() and test_memcg_low(), there is an array of four
sibling cgroups. All but one of these sibling groups does a 50MB
allocation, and the group that does no allocation is the third of four in
the array. This is not a problem per se, but makes it a bit tricky to do
some assertions in test_memcg_low(), as we want to make assertions on the
siblings based on whether or not they performed allocations. Having a
static index before which all groups have performed an allocation makes
this cleaner.
This patch therefore reorders the sibling groups so that the group that
performs no allocations is the last in the array. A follow-on patch will
leverage this to fix a bug in the test that incorrectly asserts that a
sibling group that had performed an allocation, but only had protection
from its parent, will not observe any memory.events.low events during
reclaim.
Link: https://lkml.kernel.org/r/20220423155619.3669555-1-void@manifault.com
Link: https://lkml.kernel.org/r/20220423155619.3669555-2-void@manifault.com
Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Running cgroup kselftest with O= fails to run the with_stress test due
to hardcoded ./test_core. Find test_core binary using the OUTPUT directory.
Fixes: 1a99fcc035 ("selftests: cgroup: Run test_core under interfering stress")
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
After commit 0e4b01df86 ("mm, memcg: throttle allocators when failing
reclaim over memory.high") allocating memory over memory.high became very
time consuming. But it's exactly what the memory.high test from cgroup
kselftests is doing: it tries to allocate 100M with 30M memory.high value.
It takes forever to complete.
In order to keep it passing (or failing) in a reasonable amount of time
let's try to allocate only a little over 30M: 31M to be precise.
With this change test_memcontrol finishes in a reasonable amount of
time:
$ time ./test_memcontrol
ok 1 test_memcg_subtree_control
ok 2 test_memcg_current
ok 3 test_memcg_min
ok 4 test_memcg_low
ok 5 test_memcg_high
ok 6 test_memcg_max
ok 7 test_memcg_oom_events
ok 8 test_memcg_swap_max
ok 9 test_memcg_sock
ok 10 test_memcg_oom_group_leaf_events
ok 11 test_memcg_oom_group_parent_events
ok 12 test_memcg_oom_group_score_events
real 0m2.273s
user 0m0.064s
sys 0m0.739s
Link: https://lkml.kernel.org/r/20220415000133.3955987-3-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: David Vernet <void@manifault.com>
Cc: Chris Down <chris@chrisdown.name>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Most of the test suites in tools/testing/selftests contain a config file
that specifies which kernel config options need to be present in order for
the test suite to be able to run and perform meaningful validation. There
is no config file for the tools/testing/selftests/cgroup test suite, so
this patch adds one.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The cgroup cpu controller selftests have a test_cpucg_max() testcase
that validates the behavior of the cpu.max knob. Let's also add a
testcase that verifies that the behavior works correctly when set on a
nested cgroup.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The cgroup cpu controller test suite has a number of testcases that
validate the expected behavior of the cpu.weight knob, but none for
cpu.max. This testcase fixes that by adding a testcase for cpu.max as well.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The cgroup cpu controller test suite currently contains a testcase called
test_cpucg_nested_weight_underprovisioned() which verifies the expected
behavior of cpu.weight when applied to nested cgroups. That first testcase
validated the expected behavior when the processes in the leaf cgroups
overcommitted the system. This patch adds a complementary
test_cpucg_nested_weight_underprovisioned() testcase which validates
behavior when those leaf cgroups undercommit the system.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The cgroup cpu controller tests in
tools/testing/selftests/cgroup/test_cpu.c have some testcases that validate
the expected behavior of setting cpu.weight on cgroups, and then hogging
CPUs. What is still missing from the suite is a testcase that validates
nested cgroups. This patch adds test_cpucg_nested_weight_overprovisioned(),
which validates that a parent's cpu.weight will override its children if
they overcommit a host, and properly protect any sibling groups of that
parent.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
test_cpu.c includes testcases that validate the cgroup cpu controller.
This patch adds a new testcase called test_cpucg_weight_underprovisioned()
that verifies that processes with different cpu.weight that are all running
on an underprovisioned system, still get roughly the same amount of cpu
time.
Because test_cpucg_weight_underprovisioned() is very similar to
test_cpucg_weight_overprovisioned(), this patch also pulls the common logic
into a separate helper function that is invoked from both testcases, and
which uses function pointers to invoke the unique portions of the
testcases.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
test_cpu.c includes testcases that validate the cgroup cpu controller.
This patch adds a new testcase called test_cpucg_weight_overprovisioned()
that verifies the expected behavior of creating multiple processes with
different cpu.weight, on a system that is overprovisioned.
So as to avoid code duplication, this patch also updates cpu_hog_func_param
to take a new hog_clock_type enum which informs how time is counted in
hog_cpus_timed() (either process time or wall clock time).
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
test_cpu.c includes testcases that validate the cgroup cpu controller.
This patch adds a new testcase called test_cpucg_stats() that verifies the
expected behavior of the cpu.stat interface. In doing so, we define a
new hog_cpus_timed() function which takes a cpu_hog_func_param struct
that configures how many CPUs it uses, and how long it runs. Future
patches will also spawn threads that hog CPUs, so this function will
eventually serve those use-cases as well.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The cgroup selftests suite currently contains tests that validate various
aspects of cgroup, such as validating the expected behavior for memory
controllers, the expected behavior of cgroup.procs, etc. There are no tests
that validate the expected behavior of the cgroup cpu controller.
This patch therefore adds a new test_cpu.c file that will contain cpu
controller testcases. The file currently only contains a single testcase
that validates creating nested cgroups with cgroup.subtree_control
including cpu. Future patches will add more sophisticated testcases that
validate functional aspects of the cpu controller.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When a task is writing to an fd opened by a different task, the perm check
should use the cgroup namespace of the latter task. Add a test for it.
Tested-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When a task is writing to an fd opened by a different task, the perm check
should use the credentials of the latter task. Add a test for it.
Tested-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
0644 is an odd perm to create a cgroup which is a directory. Use the regular
0755 instead. This is necessary for euid switching test case.
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
ARRAY_SIZE is defined in several selftests. Remove definitions from
individual test files and include header file for the define instead.
ARRAY_SIZE define is added in a separate patch to prepare for this
change.
Remove ARRAY_SIZE from cgroup_util.h and pickup the one defined in
kselftest.h.
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
When building selftests/cgroup: with clang the following error are seen:
clang -Wall -pthread test_memcontrol.c cgroup_util.c ../clone3/clone3_selftests.h -o .../builds/current/kselftest/cgroup/test_memcontrol
clang: error: cannot specify -o when generating multiple output files
make[3]: *** [../lib.mk:146: .../builds/current/kselftest/cgroup/test_memcontrol] Error 1
Rework to add the header files to LOCAL_HDRS before including ../lib.mk,
since the dependency is evaluated in '$(OUTPUT)/%:%.c $(LOCAL_HDRS)' in
file lib.mk.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
On older distros struct clone_args does not have a cgroup member,
leading to build errors:
cgroup_util.c: In function 'clone_into_cgroup':
cgroup_util.c:343:4: error: 'struct clone_args' has no member named 'cgroup'
cgroup_util.c:346:33: error: invalid application of 'sizeof' to incomplete
type 'struct clone_args'
But the selftests already have a locally defined version of the
structure which is up to date, called __clone_args.
So use __clone_args which fixes the error.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sachin Sant <sachinp@linux.vnet.ibm.com>>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Add some tests to cover the kernel memory accounting functionality. These
are covering some issues (and changes) we had recently.
1) A test which allocates a lot of negative dentries, checks memcg slab
statistics, creates memory pressure by setting memory.max to some low
value and checks that some number of slabs was reclaimed.
2) A test which covers side effects of memcg destruction: it creates
and destroys a large number of sub-cgroups, each containing a
multi-threaded workload which allocates and releases some kernel
memory. Then it checks that the charge ans memory.stats do add up on
the parent level.
3) A test which reads /proc/kpagecgroup and implicitly checks that it
doesn't crash the system.
4) A test which spawns a large number of threads and checks that the
kernel stacks accounting works as expected.
5) A test which checks that living charged slab objects are not
preventing the memory cgroup from being released after being deleted by
a user.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lkml.kernel.org/r/20200623174037.3951353-19-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull SPDX updates from Greg KH:
"Here are three SPDX patches for 5.7-rc1.
One fixes up the SPDX tag for a single driver, while the other two go
through the tree and add SPDX tags for all of the .gitignore files as
needed.
Nothing too complex, but you will get a merge conflict with your
current tree, that should be trivial to handle (one file modified by
two things, one file deleted.)
All three of these have been in linux-next for a while, with no
reported issues other than the merge conflict"
* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
ASoC: MT6660: make spdxcheck.py happy
.gitignore: add SPDX License Identifier
.gitignore: remove too obvious comments
Expand the cgroup test-suite to include tests for CLONE_INTO_CGROUP.
This adds the following tests:
- CLONE_INTO_CGROUP manages to clone a process directly into a correctly
delegated cgroup
- CLONE_INTO_CGROUP fails to clone a process into a cgroup that has been
removed after we've opened an fd to it
- CLONE_INTO_CGROUP fails to clone a process into an invalid domain
cgroup
- CLONE_INTO_CGROUP adheres to the no internal process constraint
- CLONE_INTO_CGROUP works with the freezer feature
Cc: Tejun Heo <tj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: cgroups@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add new test to verify that a cgroup with dead processes can be destroyed.
The test spawns a child process which allocates and touches 100MB of RAM
to ensure prolonged exit. Subsequently it kills the child, waits until
the cgroup containing the child is empty and destroys the cgroup.
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
[mkoutny@suse.com: Fix typo in test_cgcore_destroy comment]
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The "c_threads" variable is used in the error handling code before it
has been initialized
Fixes: 11318989c3 ("selftests: cgroup: Add task migration tests")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
It is necessary to set fd to -1 when inotify_add_watch() fails in
cg_prepare_for_wait. Otherwise the fd which has been closed in
cg_prepare_for_wait may be misused in other functions such as
cg_enter_and_wait_for_frozen and cg_freeze_wait.
Fixes: 5313bfe425 ("selftests: cgroup: add freezer controller self-tests")
Signed-off-by: Hewenliang <hewenliang4@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
test_core tests various cgroup creation/removal and task migration
paths. Run the tests repeatedly with interfering noise (for lockdep
checks). Currently, forking noise and subsystem enabled/disabled
switching are the implemented noises.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add two new tests that verify that thread and threadgroup migrations
work as expected.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Simplify task migration by being oblivious about its PID during
migration. This allows to easily migrate individual threads as well.
This change brings no functional change and prepares grounds for thread
granularity migrating tests.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add a new cgroup freezer selftest, which checks that if a cgroup is
frozen, their new child cgroups will properly inherit the frozen
state.
It creates a parent cgroup, freezes it, creates a child cgroup
and populates it with a dummy process. Then it checks that both
parent and child cgroup are frozen.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
On my laptop most memcg kselftests were being skipped because it claimed
cgroup v2 hierarchy wasn't mounted, but this isn't correct. Instead, it
seems current systemd HEAD mounts it with the name "cgroup2" instead of
"cgroup":
% grep cgroup /proc/mounts
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate 0 0
I can't think of a reason to need to check fs_spec explicitly
since it's arbitrary, so we can just rely on fs_vfstype.
After these changes, `make TARGETS=cgroup kselftest` actually runs the
cgroup v2 tests in more cases.
Link: http://lkml.kernel.org/r/20190723210737.GA487@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cgroup testing relys on the root cgroup's subtree_control setting,
If the 'memory' controller isn't set, some test cases will be failed
as following:
$sudo ./test_core
not ok 1 test_cgcore_internal_process_constraint
ok 2 test_cgcore_top_down_constraint_enable
not ok 3 test_cgcore_top_down_constraint_disable
...
To correct this unexpected failure, this patch write the 'memory' to
subtree_control of root to get a right result.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Claudio Zumbo <claudioz@fb.com>
Cc: Claudio <claudiozumbo@gmail.com>
Cc: linux-kselftest@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The cgroup testing relies on the root cgroup's subtree_control setting,
If the 'memory' controller isn't set, all test cases will be failed
as following:
$ sudo ./test_memcontrol
not ok 1 test_memcg_subtree_control
not ok 2 test_memcg_current
ok 3 # skip test_memcg_min
not ok 4 test_memcg_low
not ok 5 test_memcg_high
not ok 6 test_memcg_max
not ok 7 test_memcg_oom_events
ok 8 # skip test_memcg_swap_max
not ok 9 test_memcg_sock
not ok 10 test_memcg_oom_group_leaf_events
not ok 11 test_memcg_oom_group_parent_events
not ok 12 test_memcg_oom_group_score_events
To correct this unexpected failure, this patch write the 'memory' to
subtree_control of root to get a right result.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Jay Kamat <jgkamat@fb.com>
Cc: linux-kselftest@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
