From patchwork Mon Nov 4 15:13:20 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miao Xie X-Patchwork-Id: 3136161 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 46A6B9F432 for ; Mon, 4 Nov 2013 15:12:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2C50420534 for ; Mon, 4 Nov 2013 15:12:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E61B4200D6 for ; Mon, 4 Nov 2013 15:12:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753615Ab3KDPMp (ORCPT ); Mon, 4 Nov 2013 10:12:45 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:51952 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753436Ab3KDPMm (ORCPT ); Mon, 4 Nov 2013 10:12:42 -0500 X-IronPort-AV: E=Sophos;i="4.93,632,1378828800"; d="scan'208";a="8942957" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 04 Nov 2013 23:09:09 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id rA4FCVjO031734 for ; Mon, 4 Nov 2013 23:12:31 +0800 Received: from miao.fnst.cn.fujitsu.com ([10.167.226.106]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2013110423104103-2750346 ; Mon, 4 Nov 2013 23:10:41 +0800 From: Miao Xie To: linux-btrfs@vger.kernel.org Subject: [PATCH 1/7] Btrfs: remove unnecessary initialization and memory barrior in shrink_delalloc() Date: Mon, 4 Nov 2013 23:13:20 +0800 Message-Id: <1383578006-22691-2-git-send-email-miaox@cn.fujitsu.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1383578006-22691-1-git-send-email-miaox@cn.fujitsu.com> References: <1383578006-22691-1-git-send-email-miaox@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/11/04 23:10:41, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/11/04 23:10:41, Serialize complete at 2013/11/04 23:10:41 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Signed-off-by: Miao Xie Reviewed-by: David Sterba --- fs/btrfs/extent-tree.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 1d238ed..abe65ed 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4016,15 +4016,14 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig, u64 delalloc_bytes; u64 max_reclaim; long time_left; - unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT; - int loops = 0; + unsigned long nr_pages; + int loops; enum btrfs_reserve_flush_enum flush; trans = (struct btrfs_trans_handle *)current->journal_info; block_rsv = &root->fs_info->delalloc_block_rsv; space_info = block_rsv->space_info; - smp_mb(); delalloc_bytes = percpu_counter_sum_positive( &root->fs_info->delalloc_bytes); if (delalloc_bytes == 0) { @@ -4034,6 +4033,7 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig, return; } + loops = 0; while (delalloc_bytes && loops < 3) { max_reclaim = min(delalloc_bytes, to_reclaim); nr_pages = max_reclaim >> PAGE_CACHE_SHIFT; @@ -4064,7 +4064,6 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig, if (time_left) break; } - smp_mb(); delalloc_bytes = percpu_counter_sum_positive( &root->fs_info->delalloc_bytes); }