From patchwork Tue Jan 12 18:35:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 8020151 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 4C7A49F716 for ; Tue, 12 Jan 2016 18:35:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6B31A203F3 for ; Tue, 12 Jan 2016 18:35:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69251203FB for ; Tue, 12 Jan 2016 18:35:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752905AbcALSfn (ORCPT ); Tue, 12 Jan 2016 13:35:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60927 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752739AbcALSfl (ORCPT ); Tue, 12 Jan 2016 13:35:41 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 90836C0B2B7D; Tue, 12 Jan 2016 18:35:41 +0000 (UTC) Received: from bfoster.bfoster (dhcp-41-49.bos.redhat.com [10.18.41.49]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u0CIZftc024881; Tue, 12 Jan 2016 13:35:41 -0500 Received: by bfoster.bfoster (Postfix, from userid 1000) id E0ADC1245C6; Tue, 12 Jan 2016 13:35:39 -0500 (EST) From: Brian Foster To: linux-fsdevel@vger.kernel.org Cc: dchinner@redhat.com, jbacik@fb.com, jack@suse.cz Subject: [RFC PATCH v5 2/2] wb: inode writeback list tracking tracepoints Date: Tue, 12 Jan 2016 13:35:39 -0500 Message-Id: <1452623739-32542-3-git-send-email-bfoster@redhat.com> In-Reply-To: <1452623739-32542-1-git-send-email-bfoster@redhat.com> References: <1452623739-32542-1-git-send-email-bfoster@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@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 The per-sb inode writeback list tracks inodes currently under writeback to facilitate efficient sync processing. In particular, it ensures that sync only needs to walk through a list of inodes affected by the sync. Add a couple tracepoints to help identify when inodes are added/removed to and from the writeback lists. Piggyback off of the writeback lazytime tracepoint template as it already tracks the relevant inode information. Signed-off-by: Brian Foster --- fs/fs-writeback.c | 17 +++++++++++++---- include/trace/events/writeback.h | 22 ++++++++++++++++++---- 2 files changed, 31 insertions(+), 8 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 6821347..672664b 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -954,8 +954,10 @@ void sb_mark_inode_writeback(struct inode *inode) if (list_empty(&inode->i_wb_list)) { spin_lock_irqsave(&sb->s_inode_wblist_lock, flags); - if (list_empty(&inode->i_wb_list)) + if (list_empty(&inode->i_wb_list)) { list_add_tail(&inode->i_wb_list, &sb->s_inodes_wb); + trace_sb_mark_inode_writeback(inode); + } spin_unlock_irqrestore(&sb->s_inode_wblist_lock, flags); } } @@ -970,7 +972,10 @@ void sb_clear_inode_writeback(struct inode *inode) if (!list_empty(&inode->i_wb_list)) { spin_lock_irqsave(&sb->s_inode_wblist_lock, flags); - list_del_init(&inode->i_wb_list); + if (!list_empty(&inode->i_wb_list)) { + list_del_init(&inode->i_wb_list); + trace_sb_clear_inode_writeback(inode); + } spin_unlock_irqrestore(&sb->s_inode_wblist_lock, flags); } } @@ -2202,8 +2207,10 @@ static void wait_sb_inodes(struct super_block *sb) * The mapping can be cleaned before we wait on the inode since * we do not have the mapping lock. */ - if (!mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) + if (!mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) { + trace_sb_clear_inode_writeback(inode); continue; + } spin_unlock_irq(&sb->s_inode_wblist_lock); @@ -2239,8 +2246,10 @@ static void wait_sb_inodes(struct super_block *sb) if (list_empty(&inode->i_wb_list)) list_add_tail(&inode->i_wb_list, &sb->s_inodes_wb); spin_unlock(&sb->s_inode_wblist_lock); - } else + } else { WARN_ON(!list_empty(&inode->i_wb_list)); + trace_sb_clear_inode_writeback(inode); + } spin_unlock_irq(&mapping->tree_lock); iput(inode); diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index fff846b..962a7f1 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -727,7 +727,7 @@ DEFINE_EVENT(writeback_single_inode_template, writeback_single_inode, TP_ARGS(inode, wbc, nr_to_write) ); -DECLARE_EVENT_CLASS(writeback_lazytime_template, +DECLARE_EVENT_CLASS(writeback_inode_template, TP_PROTO(struct inode *inode), TP_ARGS(inode), @@ -754,25 +754,39 @@ DECLARE_EVENT_CLASS(writeback_lazytime_template, show_inode_state(__entry->state), __entry->mode) ); -DEFINE_EVENT(writeback_lazytime_template, writeback_lazytime, +DEFINE_EVENT(writeback_inode_template, writeback_lazytime, TP_PROTO(struct inode *inode), TP_ARGS(inode) ); -DEFINE_EVENT(writeback_lazytime_template, writeback_lazytime_iput, +DEFINE_EVENT(writeback_inode_template, writeback_lazytime_iput, TP_PROTO(struct inode *inode), TP_ARGS(inode) ); -DEFINE_EVENT(writeback_lazytime_template, writeback_dirty_inode_enqueue, +DEFINE_EVENT(writeback_inode_template, writeback_dirty_inode_enqueue, TP_PROTO(struct inode *inode), TP_ARGS(inode) ); +/* + * Inode writeback list tracking. + */ + +DEFINE_EVENT(writeback_inode_template, sb_mark_inode_writeback, + TP_PROTO(struct inode *inode), + TP_ARGS(inode) +); + +DEFINE_EVENT(writeback_inode_template, sb_clear_inode_writeback, + TP_PROTO(struct inode *inode), + TP_ARGS(inode) +); + #endif /* _TRACE_WRITEBACK_H */ /* This part must be outside protection */