Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934305AbbHJKSI (ORCPT ); Mon, 10 Aug 2015 06:18:08 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44209 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934248AbbHJKR5 (ORCPT ); Mon, 10 Aug 2015 06:17:57 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Michal Hocko" , "Theodore Ts'o" Date: Mon, 10 Aug 2015 12:12:31 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 067/110] ext4: replace open coded nofail allocation in ext4_free_blocks() In-Reply-To: X-SA-Exim-Connect-IP: 2.173.94.72 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1840 Lines: 56 3.2.71-rc1 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 [bwh: Backported to 3.2: - Adjust context - s/ext4_free_data_cachep/ext4_free_ext_cachep/] Signed-off-by: Ben Hutchings --- fs/ext4/mballoc.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4720,18 +4720,12 @@ 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_ext_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_ext_cachep, + GFP_NOFS|__GFP_NOFAIL); new_entry->start_cluster = bit; new_entry->group = block_group; new_entry->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/