From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:42242 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754062AbbJRCUq (ORCPT ); Sat, 17 Oct 2015 22:20:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Layton , Trond Myklebust Subject: [PATCH 4.2 136/258] NFS: Fix a write performance regression Date: Sat, 17 Oct 2015 18:57:29 -0700 Message-Id: <20151018014736.573690602@linuxfoundation.org> In-Reply-To: <20151018014729.976101177@linuxfoundation.org> References: <20151018014729.976101177@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 4.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit 8fa4592a14ebb3c22a21d846d1e4f65dab7d1a7c upstream. If all other conditions in nfs_can_extend_write() are met, and there are no locks, then we should be able to assume close-to-open semantics and the ability to extend our write to cover the whole page. With this patch, the xfstests generic/074 test completes in 242s instead of >1400s on my test rig. Fixes: bd61e0a9c852 ("locks: convert posix locks to file_lock_context") Cc: Jeff Layton Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/write.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1223,7 +1223,7 @@ static int nfs_can_extend_write(struct f return 1; if (!flctx || (list_empty_careful(&flctx->flc_flock) && list_empty_careful(&flctx->flc_posix))) - return 0; + return 1; /* Check to see if there are whole file write locks */ ret = 0;