From efee5a0c62d827c0eca7044c2d14dd3324b325aa Mon Sep 17 00:00:00 2001 From: Rebecca Schultz Zavin Date: Fri, 13 Dec 2013 14:24:14 -0800 Subject: [PATCH] gpu: ion: Fix lockdep issue in ion_page_pool 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 [jstultz: modified patch to apply to staging directory] Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ion/ion_page_pool.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) 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); } -- 2.7.4