diff options
author | Christoph Lameter <clameter@sgi.com> | 2006-03-25 03:06:45 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-25 08:22:49 -0800 |
commit | e00946fe2351307eb3eda7a3343530f6d2d1af2e (patch) | |
tree | 1567b4abe0ed56fbd960943da2c52278ea196c02 | |
parent | 3ded175a4b7a4548f3358dcf5f3ad65f63cdb4ed (diff) | |
download | linux-e00946fe2351307eb3eda7a3343530f6d2d1af2e.tar.bz2 |
[PATCH] slab: Bypass free lists for __drain_alien_cache()
__drain_alien_cache() currently drains objects by freeing them to the
(remote) freelists of the original node. However, each node also has a
shared list containing objects to be used on any processor of that node.
We can avoid a number of remote node accesses by copying the pointers to
the free objects directly into the remote shared array.
And while we are at it: Skip alien draining if the alien cache spinlock is
already taken.
Kiran reported that this is a performance benefit.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | mm/slab.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/mm/slab.c b/mm/slab.c index dee857a8680b..351aa6c587f7 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -971,6 +971,13 @@ static void __drain_alien_cache(struct kmem_cache *cachep, if (ac->avail) { spin_lock(&rl3->list_lock); + /* + * Stuff objects into the remote nodes shared array first. + * That way we could avoid the overhead of putting the objects + * into the free lists and getting them back later. + */ + transfer_objects(rl3->shared, ac, ac->limit); + free_block(cachep, ac->entry, ac->avail, node); ac->avail = 0; spin_unlock(&rl3->list_lock); @@ -986,8 +993,8 @@ static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) if (l3->alien) { struct array_cache *ac = l3->alien[node]; - if (ac && ac->avail) { - spin_lock_irq(&ac->lock); + + if (ac && ac->avail && spin_trylock_irq(&ac->lock)) { __drain_alien_cache(cachep, ac, node); spin_unlock_irq(&ac->lock); } |