diff mbox

[040/115] gpu: ion: Fix lockdep issue in ion_page_pool

Message ID 1386973529-4884-41-git-send-email-john.stultz@linaro.org
State Accepted
Headers show

Commit Message

John Stultz Dec. 13, 2013, 10:24 p.m. UTC 
From: Rebecca Schultz Zavin <rebecca@android.com>

Currently the mutex is held while kmalloc is called, under a low memory
condition this might trigger the shrinker which also takes this mutex.
Refactor so the mutex is not held during allocation.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/staging/android/ion/ion_page_pool.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/drivers/staging/android/ion/ion_page_pool.c b/drivers/staging/android/ion/ion_page_pool.c
index ea45380..20790eb 100644
--- a/drivers/staging/android/ion/ion_page_pool.c
+++ b/drivers/staging/android/ion/ion_page_pool.c
@@ -53,6 +53,8 @@  static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
 	item = kmalloc(sizeof(struct ion_page_pool_item), GFP_KERNEL);
 	if (!item)
 		return -ENOMEM;
+
+	mutex_lock(&pool->mutex);
 	item->page = page;
 	if (PageHighMem(page)) {
 		list_add_tail(&item->list, &pool->high_items);
@@ -61,6 +63,7 @@  static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
 		list_add_tail(&item->list, &pool->low_items);
 		pool->low_count++;
 	}
+	mutex_unlock(&pool->mutex);
 	return 0;
 }
 
@@ -110,9 +113,7 @@  void ion_page_pool_free(struct ion_page_pool *pool, struct page* page)
 {
 	int ret;
 
-	mutex_lock(&pool->mutex);
 	ret = ion_page_pool_add(pool, page);
-	mutex_unlock(&pool->mutex);
 	if (ret)
 		ion_page_pool_free_pages(pool, page);
 }