mm/list_lru: introduce list_lru_shrink_walk_irq()

Provide list_lru_shrink_walk_irq() and let it behave like
list_lru_walk_one() except that it locks the spinlock with
spin_lock_irq().  This is used by scan_shadow_nodes() because its lock
nests within the i_pages lock which is acquired with IRQ.  This change
allows to use proper locking promitives instead hand crafted
lock_irq_disable() plus spin_lock().

There is no EXPORT_SYMBOL provided because the current user is in-kernel
only.

Add list_lru_shrink_walk_irq() which acquires the spinlock with the
proper locking primitives.

Link: http://lkml.kernel.org/r/20180716111921.5365-5-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sebastian Andrzej Siewior 2018-08-17 15:49:55 -07:00 committed by Linus Torvalds
parent 6e018968f8
commit 6b51e88199
3 changed files with 42 additions and 6 deletions

View file

@ -483,13 +483,9 @@ out:
static unsigned long scan_shadow_nodes(struct shrinker *shrinker,
struct shrink_control *sc)
{
unsigned long ret;
/* list_lru lock nests inside the IRQ-safe i_pages lock */
local_irq_disable();
ret = list_lru_shrink_walk(&shadow_nodes, sc, shadow_lru_isolate, NULL);
local_irq_enable();
return ret;
return list_lru_shrink_walk_irq(&shadow_nodes, sc, shadow_lru_isolate,
NULL);
}
static struct shrinker workingset_shadow_shrinker = {