Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932485AbbFWJu5 (ORCPT ); Tue, 23 Jun 2015 05:50:57 -0400 Received: from cantor2.suse.de ([195.135.220.15]:35393 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754152AbbFWJuo (ORCPT ); Tue, 23 Jun 2015 05:50:44 -0400 From: Michal Hocko To: "Theodore Ts'o" Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, , LKML Subject: [PATCH] ext4: replace open coded nofail allocation Date: Tue, 23 Jun 2015 11:50:37 +0200 Message-Id: <1435053037-1451-1-git-send-email-mhocko@suse.cz> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1830 Lines: 55 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 --- Hi Ted, I am sorry for seding these changes one at the time but I haven't found a proper way to find all of them automatically. So I am discovering them as I check the code due to other reasons. Thanks! 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 8d1e60214ef0..41260489d3bc 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4800,18 +4800,12 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, /* * 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; -- 2.1.4 -- 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/