From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754718Ab3LMWlx (ORCPT ); Fri, 13 Dec 2013 17:41:53 -0500 Received: from mail-pa0-f51.google.com ([209.85.220.51]:57333 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753823Ab3LMW1M (ORCPT ); Fri, 13 Dec 2013 17:27:12 -0500 From: John Stultz To: LKML Cc: Greg KH , Android Kernel Team , Sumit Semwal , Jesse Barker , Colin Cross , Rebecca Schultz Zavin , John Stultz Subject: [PATCH 040/115] gpu: ion: Fix lockdep issue in ion_page_pool Date: Fri, 13 Dec 2013 14:24:14 -0800 Message-Id: <1386973529-4884-41-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386973529-4884-1-git-send-email-john.stultz@linaro.org> References: <1386973529-4884-1-git-send-email-john.stultz@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rebecca Schultz Zavin 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 --- 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); } -- 1.8.3.2