Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755708AbbHLJlY (ORCPT ); Wed, 12 Aug 2015 05:41:24 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:60377 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753926AbbHLI5M (ORCPT ); Wed, 12 Aug 2015 04:57:12 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Michal Hocko , "Theodore Ts'o" , Luis Henriques Subject: [PATCH 3.16.y-ckt 009/118] ext4: replace open coded nofail allocation in ext4_free_blocks() Date: Wed, 12 Aug 2015 09:55:11 +0100 Message-Id: <1439369820-27005-10-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1439369820-27005-1-git-send-email-luis.henriques@canonical.com> References: <1439369820-27005-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1870 Lines: 54 3.16.7-ckt16 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Michal Hocko commit 7444a072c387a93ebee7066e8aee776954ab0e41 upstream. ext4_free_blocks is looping around the allocation request and mimics __GFP_NOFAIL behavior without any allocation fallback strategy. Let's remove the open coded loop and replace it with __GFP_NOFAIL. Without the flag the allocator has no way to find out never-fail requirement and cannot help in any way. Signed-off-by: Michal Hocko Signed-off-by: Theodore Ts'o Signed-off-by: Luis Henriques --- fs/ext4/mballoc.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index c3e7418a6811..47f7af78675a 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4810,18 +4810,12 @@ do_more: /* * blocks being freed are metadata. these blocks shouldn't * be used until this transaction is committed + * + * We use __GFP_NOFAIL because ext4_free_blocks() is not allowed + * to fail. */ - retry: - new_entry = kmem_cache_alloc(ext4_free_data_cachep, GFP_NOFS); - if (!new_entry) { - /* - * We use a retry loop because - * ext4_free_blocks() is not allowed to fail. - */ - cond_resched(); - congestion_wait(BLK_RW_ASYNC, HZ/50); - goto retry; - } + new_entry = kmem_cache_alloc(ext4_free_data_cachep, + GFP_NOFS|__GFP_NOFAIL); new_entry->efd_start_cluster = bit; new_entry->efd_group = block_group; new_entry->efd_count = count_clusters; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/