sched/headers, cgroups: Remove the threadgroup_change_*() wrappery
threadgroup_change_begin()/end() is a pointless wrapper around
cgroup_threadgroup_change_begin()/end(), minus a might_sleep()
in the !CONFIG_CGROUPS=y case.
Remove the wrappery, move the might_sleep() (the down_read()
already has a might_sleep() check).
This debloats <linux/sched.h> a bit and simplifies this API.
Update all call sites.
No change in functionality.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 3c02404..6a3f850 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -531,8 +531,8 @@ extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem;
* cgroup_threadgroup_change_begin - threadgroup exclusion for cgroups
* @tsk: target task
*
- * Called from threadgroup_change_begin() and allows cgroup operations to
- * synchronize against threadgroup changes using a percpu_rw_semaphore.
+ * Allows cgroup operations to synchronize against threadgroup changes
+ * using a percpu_rw_semaphore.
*/
static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk)
{
@@ -543,8 +543,7 @@ static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk)
* cgroup_threadgroup_change_end - threadgroup exclusion for cgroups
* @tsk: target task
*
- * Called from threadgroup_change_end(). Counterpart of
- * cgroup_threadcgroup_change_begin().
+ * Counterpart of cgroup_threadcgroup_change_begin().
*/
static inline void cgroup_threadgroup_change_end(struct task_struct *tsk)
{
@@ -555,7 +554,11 @@ static inline void cgroup_threadgroup_change_end(struct task_struct *tsk)
#define CGROUP_SUBSYS_COUNT 0
-static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk) {}
+static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk)
+{
+ might_sleep();
+}
+
static inline void cgroup_threadgroup_change_end(struct task_struct *tsk) {}
#endif /* CONFIG_CGROUPS */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e732881..3f61baa 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -3162,34 +3162,6 @@ static inline void unlock_task_sighand(struct task_struct *tsk,
spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}
-/**
- * threadgroup_change_begin - mark the beginning of changes to a threadgroup
- * @tsk: task causing the changes
- *
- * All operations which modify a threadgroup - a new thread joining the
- * group, death of a member thread (the assertion of PF_EXITING) and
- * exec(2) dethreading the process and replacing the leader - are wrapped
- * by threadgroup_change_{begin|end}(). This is to provide a place which
- * subsystems needing threadgroup stability can hook into for
- * synchronization.
- */
-static inline void threadgroup_change_begin(struct task_struct *tsk)
-{
- might_sleep();
- cgroup_threadgroup_change_begin(tsk);
-}
-
-/**
- * threadgroup_change_end - mark the end of changes to a threadgroup
- * @tsk: task causing the changes
- *
- * See threadgroup_change_begin().
- */
-static inline void threadgroup_change_end(struct task_struct *tsk)
-{
- cgroup_threadgroup_change_end(tsk);
-}
-
#ifdef CONFIG_THREAD_INFO_IN_TASK
static inline struct thread_info *task_thread_info(struct task_struct *task)