Commit 07b17f0f authored by Yunsheng Lin's avatar Yunsheng Lin Committed by Jakub Kicinski
Browse files

page_pool: remove spinlock in page_pool_refill_alloc_cache() 



As page_pool_refill_alloc_cache() is only called by
__page_pool_get_cached(), which assumes non-concurrent access
as suggested by the comment in __page_pool_get_cached(), and
ptr_ring allows concurrent access between consumer and producer,
so remove the spinlock in page_pool_refill_alloc_cache().

Signed-off-by: default avatarYunsheng Lin <linyunsheng@huawei.com>
Acked-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20220107090042.13605-1-linyunsheng@huawei.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 6738fc77

net/core/page_pool.c

+0 −4
Original line number Diff line number Diff line
@@ -130,9 +130,6 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool) 
	pref_nid = numa_mem_id(); /* will be zero like page_to_nid() */

#endif



	/* Slower-path: Get pages from locked ring queue */

	spin_lock(&r->consumer_lock);



	/* Refill alloc array, but only if NUMA match */

	do {

		page = __ptr_ring_consume(r);
@@ -157,7 +154,6 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool) 
	if (likely(pool->alloc.count > 0))

		page = pool->alloc.cache[--pool->alloc.count];



	spin_unlock(&r->consumer_lock);

	return page;

}