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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 40FA9C433E0 for ; Mon, 18 Jan 2021 20:37:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12E1E22B39 for ; Mon, 18 Jan 2021 20:37:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388346AbhARKgw (ORCPT ); Mon, 18 Jan 2021 05:36:52 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:42480 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388494AbhARJQ3 (ORCPT ); Mon, 18 Jan 2021 04:16:29 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610961300; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jLhF9w9+aKkcqwkuEudMpLh/G4t/5zGyYhNSMg5g2pQ=; b=YOHfBvZI2HmsbVEzvrUwjPBLFUpipuX1xaxL8UQUbNf31LUBmnJ0gsPeXgIvDxwQs4H0Kx H0ehymLat+t2GLpvvMQr0IiEKuzyqn9T/3qC5qTikpC4i61q84b8G9qT8yoSeN/8K0SE1x gOqwKNs8XxVUmYSPIyWz2bg9G3zglfY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-146-Ynkkr-rzN4OdDpCmyLHksg-1; Mon, 18 Jan 2021 04:10:53 -0500 X-MC-Unique: Ynkkr-rzN4OdDpCmyLHksg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DED441005513; Mon, 18 Jan 2021 09:10:52 +0000 (UTC) Received: from [10.72.12.125] (ovpn-12-125.pek2.redhat.com [10.72.12.125]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 59CFD17511; Mon, 18 Jan 2021 09:10:51 +0000 (UTC) Subject: Re: [PATCH v3] ceph: defer flushing the capsnap if the Fb is used To: Jeff Layton Cc: idryomov@gmail.com, pdonnell@redhat.com, ceph-devel@vger.kernel.org References: <20210110020140.141727-1-xiubli@redhat.com> From: Xiubo Li Message-ID: <376245cf-a60d-6ddb-6ab3-894a491b854e@redhat.com> Date: Mon, 18 Jan 2021 17:10:47 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org On 2021/1/13 5:48, Jeff Layton wrote: > On Sun, 2021-01-10 at 10:01 +0800, xiubli@redhat.com wrote: >> From: Xiubo Li >> >> If the Fb cap is used it means the current inode is flushing the >> dirty data to OSD, just defer flushing the capsnap. >> >> URL: https://tracker.ceph.com/issues/48679 >> URL: https://tracker.ceph.com/issues/48640 >> Signed-off-by: Xiubo Li >> --- >> >> V3: >> - Add more comments about putting the inode ref >> - A small change about the code style >> >> V2: >> - Fix inode reference leak bug >> >>  fs/ceph/caps.c | 32 +++++++++++++++++++------------- >>  fs/ceph/snap.c | 6 +++--- >>  2 files changed, 22 insertions(+), 16 deletions(-) >> > Hi Xiubo, > > This patch seems to cause hangs in some xfstests (generic/013, in > particular). I'll take a closer look when I have a chance, but I'm > dropping this for now. Okay. BTW, what's your test commands to reproduce it ? I will take a look when I am free these days or later. BRs > > -- Jeff > > >> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c >> index abbf48fc6230..b00234cf3b04 100644 >> --- a/fs/ceph/caps.c >> +++ b/fs/ceph/caps.c >> @@ -3047,6 +3047,7 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, >>  { >>   struct inode *inode = &ci->vfs_inode; >>   int last = 0, put = 0, flushsnaps = 0, wake = 0; >> + bool check_flushsnaps = false; >> >> >> >> >>   spin_lock(&ci->i_ceph_lock); >>   if (had & CEPH_CAP_PIN) >> @@ -3063,26 +3064,17 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, >>   if (had & CEPH_CAP_FILE_BUFFER) { >>   if (--ci->i_wb_ref == 0) { >>   last++; >> + /* put the ref held by ceph_take_cap_refs() */ >>   put++; >> + check_flushsnaps = true; >>   } >>   dout("put_cap_refs %p wb %d -> %d (?)\n", >>   inode, ci->i_wb_ref+1, ci->i_wb_ref); >>   } >> - if (had & CEPH_CAP_FILE_WR) >> + if (had & CEPH_CAP_FILE_WR) { >>   if (--ci->i_wr_ref == 0) { >>   last++; >> - if (__ceph_have_pending_cap_snap(ci)) { >> - struct ceph_cap_snap *capsnap = >> - list_last_entry(&ci->i_cap_snaps, >> - struct ceph_cap_snap, >> - ci_item); >> - capsnap->writing = 0; >> - if (ceph_try_drop_cap_snap(ci, capsnap)) >> - put++; >> - else if (__ceph_finish_cap_snap(ci, capsnap)) >> - flushsnaps = 1; >> - wake = 1; >> - } >> + check_flushsnaps = true; >>   if (ci->i_wrbuffer_ref_head == 0 && >>   ci->i_dirty_caps == 0 && >>   ci->i_flushing_caps == 0) { >> @@ -3094,6 +3086,20 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had, >>   if (!__ceph_is_any_real_caps(ci) && ci->i_snap_realm) >>   drop_inode_snap_realm(ci); >>   } >> + } >> + if (check_flushsnaps && __ceph_have_pending_cap_snap(ci)) { >> + struct ceph_cap_snap *capsnap = >> + list_last_entry(&ci->i_cap_snaps, >> + struct ceph_cap_snap, >> + ci_item); >> + capsnap->writing = 0; >> + if (ceph_try_drop_cap_snap(ci, capsnap)) >> + /* put the ref held by ceph_queue_cap_snap() */ >> + put++; >> + else if (__ceph_finish_cap_snap(ci, capsnap)) >> + flushsnaps = 1; >> + wake = 1; >> + } >>   spin_unlock(&ci->i_ceph_lock); >> >> >> >> >>   dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had), >> diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c >> index b611f829cb61..639fb91cc9db 100644 >> --- a/fs/ceph/snap.c >> +++ b/fs/ceph/snap.c >> @@ -561,10 +561,10 @@ void ceph_queue_cap_snap(struct ceph_inode_info *ci) >>   capsnap->context = old_snapc; >>   list_add_tail(&capsnap->ci_item, &ci->i_cap_snaps); >> >> >> >> >> - if (used & CEPH_CAP_FILE_WR) { >> + if (used & (CEPH_CAP_FILE_WR | CEPH_CAP_FILE_BUFFER)) { >>   dout("queue_cap_snap %p cap_snap %p snapc %p" >> - " seq %llu used WR, now pending\n", inode, >> - capsnap, old_snapc, old_snapc->seq); >> + " seq %llu used WR | BUFFFER, now pending\n", >> + inode, capsnap, old_snapc, old_snapc->seq); >>   capsnap->writing = 1; >>   } else { >>   /* note mtime, size NOW. */