| Message ID | 20210413065153.63431-7-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | memcontrol code cleanup and simplification | expand |
On Mon, Apr 12, 2021 at 11:58 PM Muchun Song <songmuchun@bytedance.com> wrote: > > The css_set_lock is used to guard the list of inherited objcgs. So there > is no need to uncharge kernel memory under css_set_lock. Just move it > out of the lock. > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Shakeel Butt <shakeelb@google.com>
On Tue, Apr 13, 2021 at 02:51:52PM +0800, Muchun Song wrote: > The css_set_lock is used to guard the list of inherited objcgs. So there > is no need to uncharge kernel memory under css_set_lock. Just move it > out of the lock. > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Roman Gushchin <guro@fb.com> > --- > mm/memcontrol.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 42d8c0f4ab1d..d9c7e44abcd0 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -289,9 +289,10 @@ static void obj_cgroup_release(struct percpu_ref *ref) > WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); > nr_pages = nr_bytes >> PAGE_SHIFT; > > - spin_lock_irqsave(&css_set_lock, flags); > if (nr_pages) > obj_cgroup_uncharge_pages(objcg, nr_pages); > + > + spin_lock_irqsave(&css_set_lock, flags); > list_del(&objcg->list); > spin_unlock_irqrestore(&css_set_lock, flags); > > -- > 2.11.0 >
On Tue, Apr 13, 2021 at 02:51:52PM +0800, Muchun Song wrote: > The css_set_lock is used to guard the list of inherited objcgs. So there > is no need to uncharge kernel memory under css_set_lock. Just move it > out of the lock. > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 42d8c0f4ab1d..d9c7e44abcd0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -289,9 +289,10 @@ static void obj_cgroup_release(struct percpu_ref *ref) WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); nr_pages = nr_bytes >> PAGE_SHIFT; - spin_lock_irqsave(&css_set_lock, flags); if (nr_pages) obj_cgroup_uncharge_pages(objcg, nr_pages); + + spin_lock_irqsave(&css_set_lock, flags); list_del(&objcg->list); spin_unlock_irqrestore(&css_set_lock, flags);
The css_set_lock is used to guard the list of inherited objcgs. So there is no need to uncharge kernel memory under css_set_lock. Just move it out of the lock. Signed-off-by: Muchun Song <songmuchun@bytedance.com> --- mm/memcontrol.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)