path: root/mm/dmapool.c
diff options
authorMatthew Wilcox <matthew@wil.cx>2007-12-03 12:09:33 -0500
committerMatthew Wilcox <matthew@wil.cx>2007-12-04 10:39:56 -0500
commit2cae367e4854ff055c4f5e8aacd56b0eeec9f6cb (patch)
treec28ffa400a5fc78becc9d75cdccb126fc9138ff2 /mm/dmapool.c
parente87aa773747fb5e4217d716ea22a573c03b6693a (diff)
Avoid taking waitqueue lock in dmapool
With one trivial change (taking the lock slightly earlier on wakeup from schedule), all uses of the waitq are under the pool lock, so we can use the locked (or __) versions of the wait queue functions, and avoid the extra spinlock. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Acked-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'mm/dmapool.c')
1 files changed, 5 insertions, 4 deletions
diff --git a/mm/dmapool.c b/mm/dmapool.c
index 92e886d37e90..b5ff9ce8765b 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -275,8 +275,8 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
size_t offset;
void *retval;
- restart:
spin_lock_irqsave(&pool->lock, flags);
+ restart:
list_for_each_entry(page, &pool->page_list, page_list) {
int i;
/* only cachable accesses here ... */
@@ -299,12 +299,13 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
DECLARE_WAITQUEUE(wait, current);
- add_wait_queue(&pool->waitq, &wait);
+ __add_wait_queue(&pool->waitq, &wait);
spin_unlock_irqrestore(&pool->lock, flags);
- remove_wait_queue(&pool->waitq, &wait);
+ spin_lock_irqsave(&pool->lock, flags);
+ __remove_wait_queue(&pool->waitq, &wait);
goto restart;
retval = NULL;
@@ -406,7 +407,7 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
set_bit(block, &page->bitmap[map]);
if (waitqueue_active(&pool->waitq))
- wake_up(&pool->waitq);
+ wake_up_locked(&pool->waitq);
* Resist a temptation to do
* if (!is_page_busy(bpp, page->bitmap)) pool_free_page(pool, page);