From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47DBDC43441 for ; Mon, 26 Nov 2018 09:46:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 19EC92086B for ; Mon, 26 Nov 2018 09:46:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 19EC92086B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726442AbeKZUj5 (ORCPT ); Mon, 26 Nov 2018 15:39:57 -0500 Received: from relay.sw.ru ([185.231.240.75]:49798 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726203AbeKZUj4 (ORCPT ); Mon, 26 Nov 2018 15:39:56 -0500 Received: from [172.16.25.169] (helo=localhost.localdomain) by relay.sw.ru with esmtp (Exim 4.91) (envelope-from ) id 1gRDTA-0007C0-Rn; Mon, 26 Nov 2018 12:46:21 +0300 Subject: [PATCH 2/2] fuse: Replace page without copying in fuse_writepage_in_flight() From: Kirill Tkhai To: miklos@szeredi.hu, ktkhai@virtuozzo.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 26 Nov 2018 12:46:20 +0300 Message-ID: <154322557765.18737.14337090699283695815.stgit@localhost.localdomain> In-Reply-To: <154322517208.18737.3297786654135648324.stgit@localhost.localdomain> References: <154322517208.18737.3297786654135648324.stgit@localhost.localdomain> User-Agent: StGit/0.18 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It looks like we can optimize old_req page replacement and avoid copying by simple updating the request's page. Signed-off-by: Kirill Tkhai --- fs/fuse/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index c6650c68b31a..83b54b082c86 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1778,7 +1778,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req, if (old_req->num_pages == 1 && old_req != first_req) { struct backing_dev_info *bdi = inode_to_bdi(page->mapping->host); - copy_highpage(old_req->pages[0], page); + swap(old_req->pages[0], page); spin_unlock(&fc->lock); dec_wb_stat(&bdi->wb, WB_WRITEBACK);