From 075b593f54f0f3883532cb750081cae6917bc8fe Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Fri, 26 Aug 2022 11:48:29 +0900 Subject: cgroup: Use cgroup_attach_{lock,unlock}() from cgroup_attach_task_all() No behavior changes; preparing for potential locking changes in future. Signed-off-by: Tetsuo Handa Reviewed-by:Mukesh Ojha Signed-off-by: Tejun Heo --- kernel/cgroup/cgroup-internal.h | 2 ++ kernel/cgroup/cgroup-v1.c | 6 ++---- kernel/cgroup/cgroup.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index 36b740cb3d59..2c7ecca226be 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 ff6a8099eb2a..52bb5a74a23b 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -59,8 +59,7 @@ 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; @@ -72,8 +71,7 @@ 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 65497a1a44fa..0005de2e2ed9 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -2393,7 +2393,7 @@ 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) @@ -2404,7 +2404,7 @@ 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); -- cgit