From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp

mainline inclusion from mainline-v6.1-rc1 commit 075b593f54f0f3883532cb750081cae6917bc8fe category: cleanup bugzilla: 189018, https://gitee.com/openeuler/kernel/issues/I7RPDX

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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No behavior changes; preparing for potential locking changes in future.

Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Reviewed-by:Mukesh Ojha quic_mojha@quicinc.com Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Cai Xinchen caixinchen1@huawei.com --- kernel/cgroup/cgroup-internal.h | 2 ++ kernel/cgroup/cgroup-v1.c | 6 ++---- kernel/cgroup/cgroup.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index 3f116765bb00..6fc71b98209e 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -250,6 +250,8 @@ int cgroup_migrate(struct task_struct *leader, bool threadgroup,

int cgroup_attach_task(struct cgroup *dst_cgrp, struct task_struct *leader, bool threadgroup); +void cgroup_attach_lock(bool lock_threadgroup); +void cgroup_attach_unlock(bool lock_threadgroup); struct task_struct *cgroup_procs_write_start(char *buf, bool threadgroup, bool *locked) __acquires(&cgroup_threadgroup_rwsem); diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index 647d0891cff6..d7e2d232acc4 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -57,8 +57,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) int retval = 0;

mutex_lock(&cgroup_mutex); - cpus_read_lock(); - percpu_down_write(&cgroup_threadgroup_rwsem); + cgroup_attach_lock(true); for_each_root(root) { struct cgroup *from_cgrp;

@@ -73,8 +72,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) if (retval) break; } - percpu_up_write(&cgroup_threadgroup_rwsem); - cpus_read_unlock(); + cgroup_attach_unlock(true); mutex_unlock(&cgroup_mutex);

return retval; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index d0a4a1c4c38d..2bc5bae49d20 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -2367,7 +2367,7 @@ EXPORT_SYMBOL_GPL(task_cgroup_path); * write-locking cgroup_threadgroup_rwsem. This allows ->attach() to assume that * CPU hotplug is disabled on entry. */ -static void cgroup_attach_lock(bool lock_threadgroup) +void cgroup_attach_lock(bool lock_threadgroup) { cpus_read_lock(); if (lock_threadgroup) @@ -2378,7 +2378,7 @@ static void cgroup_attach_lock(bool lock_threadgroup) * cgroup_attach_unlock - Undo cgroup_attach_lock() * @lock_threadgroup: whether to up_write cgroup_threadgroup_rwsem */ -static void cgroup_attach_unlock(bool lock_threadgroup) +void cgroup_attach_unlock(bool lock_threadgroup) { if (lock_threadgroup) percpu_up_write(&cgroup_threadgroup_rwsem);