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authorMichal Hocko <mhocko@suse.cz>2013-07-31 13:53:48 -0700
committerChanho Park <chanho61.park@samsung.com>2014-11-18 11:47:22 +0900
commit97a9fd262502e16c605c14bb847260f86f1586bf (patch)
treed41ea9d6b5ed8e841a49e7519cb346f0499721b1
parent93798daa30ecb244613ac8ab1d40ebc686af744d (diff)
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vmpressure: change vmpressure::sr_lock to spinlock
There is nothing that can sleep inside critical sections protected by this lock and those sections are really small so there doesn't make much sense to use mutex for them. Change the log to a spinlock Change-Id: I54c8361a88ec810676cf631f3754c5b860d54b01 Signed-off-by: Michal Hocko <mhocko@suse.cz> Reported-by: Tejun Heo <tj@kernel.org> Cc: Anton Vorontsov <anton.vorontsov@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Li Zefan <lizefan@huawei.com> Reviewed-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--include/linux/vmpressure.h2
-rw-r--r--mm/vmpressure.c10
2 files changed, 6 insertions, 6 deletions
diff --git a/include/linux/vmpressure.h b/include/linux/vmpressure.h
index 76be077340e..2081680e015 100644
--- a/include/linux/vmpressure.h
+++ b/include/linux/vmpressure.h
@@ -12,7 +12,7 @@ struct vmpressure {
unsigned long scanned;
unsigned long reclaimed;
/* The lock is used to keep the scanned/reclaimed above in sync. */
- struct mutex sr_lock;
+ struct spinlock sr_lock;
/* The list of vmpressure_event structs. */
struct list_head events;
diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 736a6011c2c..f4ee6a190a4 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -180,12 +180,12 @@ static void vmpressure_work_fn(struct work_struct *work)
if (!vmpr->scanned)
return;
- mutex_lock(&vmpr->sr_lock);
+ spin_lock(&vmpr->sr_lock);
scanned = vmpr->scanned;
reclaimed = vmpr->reclaimed;
vmpr->scanned = 0;
vmpr->reclaimed = 0;
- mutex_unlock(&vmpr->sr_lock);
+ spin_unlock(&vmpr->sr_lock);
do {
if (vmpressure_event(vmpr, scanned, reclaimed))
@@ -240,11 +240,11 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg,
if (!scanned)
return;
- mutex_lock(&vmpr->sr_lock);
+ spin_lock(&vmpr->sr_lock);
vmpr->scanned += scanned;
vmpr->reclaimed += reclaimed;
scanned = vmpr->scanned;
- mutex_unlock(&vmpr->sr_lock);
+ spin_unlock(&vmpr->sr_lock);
if (scanned < vmpressure_win || work_pending(&vmpr->work))
return;
@@ -367,7 +367,7 @@ void vmpressure_unregister_event(struct cgroup *cg, struct cftype *cft,
*/
void vmpressure_init(struct vmpressure *vmpr)
{
- mutex_init(&vmpr->sr_lock);
+ spin_lock_init(&vmpr->sr_lock);
mutex_init(&vmpr->events_lock);
INIT_LIST_HEAD(&vmpr->events);
INIT_WORK(&vmpr->work, vmpressure_work_fn);