diff options
author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2018-08-17 15:46:05 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-17 16:20:29 -0700 |
commit | ae1e16da14b2bca94272c9f23c930be48994b2bb (patch) | |
tree | 7fd18d588191fc977e9f02b0eda49292280d5893 | |
parent | 9ea9a68064035dee70f465f605a3e63990e33bd9 (diff) |
mm: workingset: remove local_irq_disable() from count_shadow_nodes()
Patch series "mm: use irq locking suffix instead local_irq_disable()".
A small series which avoids using local_irq_disable()/local_irq_enable()
but instead does spin_lock_irq()/spin_unlock_irq() so it is within the
context of the lock which it belongs to. Patch #1 is a cleanup where
local_irq_.*() remained after the lock was removed.
This patch (of 2):
In 0c7c1bed7e13 ("mm: make counting of list_lru_one::nr_items lockless")
the
spin_lock(&nlru->lock);
statement was replaced with
rcu_read_lock();
in __list_lru_count_one(). The comment in count_shadow_nodes() says
that the local_irq_disable() is required because the lock must be
acquired with disabled interrupts and (spin_lock()) does not do so.
Since the lock is replaced with rcu_read_lock() the local_irq_disable()
is no longer needed. The code path is
list_lru_shrink_count()
-> list_lru_count_one()
-> __list_lru_count_one()
-> rcu_read_lock()
-> list_lru_from_memcg_idx()
-> rcu_read_unlock()
Remove the local_irq_disable() statement.
Link: http://lkml.kernel.org/r/20180622151221.28167-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-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>
-rw-r--r-- | mm/workingset.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/mm/workingset.c b/mm/workingset.c index 40ee02c83978..ed8151180899 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -366,10 +366,7 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker, unsigned long nodes; unsigned long cache; - /* list_lru lock nests inside the IRQ-safe i_pages lock */ - local_irq_disable(); nodes = list_lru_shrink_count(&shadow_nodes, sc); - local_irq_enable(); /* * Approximate a reasonable limit for the radix tree nodes |