From patchwork Mon Jul 5 01:22:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiubo Li X-Patchwork-Id: 470221 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=-17.2 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, SPF_HELO_NONE, SPF_PASS 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 42558C07E95 for ; Mon, 5 Jul 2021 01:23:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BFC3613D0 for ; Mon, 5 Jul 2021 01:23:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229879AbhGEBZv (ORCPT ); Sun, 4 Jul 2021 21:25:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:55225 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229818AbhGEBZv (ORCPT ); Sun, 4 Jul 2021 21:25:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625448195; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=X1SujpTrfv65sbiVl1ncQwAtLPRsEEfrTinGF5zhOMY=; b=FIJ6CLWjUTWzMYLI7ugk0OcY1swYhO3OVN/lSwRy76HuZRlX/sbK4H7ga+bzMx8KG4CMWd bOwpLdmyF7ZkNA5YiouTVretqPbzZ8kS4FRiflF6Z3TyJpgTsb/ElJ+a7qsQzwTaBM78fO fXMMxE5/6/SNE/kMP4d0NXO27dqaBp8= 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-61-TJCwex-VOSG8-8X6PyAw9A-1; Sun, 04 Jul 2021 21:23:13 -0400 X-MC-Unique: TJCwex-VOSG8-8X6PyAw9A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C1B35802921; Mon, 5 Jul 2021 01:23:11 +0000 (UTC) Received: from lxbceph1.gsslab.pek2.redhat.com (unknown [10.72.47.117]) by smtp.corp.redhat.com (Postfix) with ESMTP id E2B0060875; Mon, 5 Jul 2021 01:23:09 +0000 (UTC) From: xiubli@redhat.com To: jlayton@kernel.org, idryomov@gmail.com Cc: pdonnell@redhat.com, ceph-devel@vger.kernel.org, Xiubo Li Subject: [PATCH v2 4/4] ceph: flush the mdlog before waiting on unsafe reqs Date: Mon, 5 Jul 2021 09:22:57 +0800 Message-Id: <20210705012257.182669-5-xiubli@redhat.com> In-Reply-To: <20210705012257.182669-1-xiubli@redhat.com> References: <20210705012257.182669-1-xiubli@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org From: Xiubo Li For the client requests who will have unsafe and safe replies from MDS daemons, in the MDS side the MDS daemons won't flush the mdlog (journal log) immediatelly, because they think it's unnecessary. That's true for most cases but not all, likes the fsync request. The fsync will wait until all the unsafe replied requests to be safely replied. Normally if there have multiple threads or clients are running, the whole mdlog in MDS daemons could be flushed in time if any request will trigger the mdlog submit thread. So usually we won't experience the normal operations will stuck for a long time. But in case there has only one client with only thread is running, the stuck phenomenon maybe obvious and the worst case it must wait at most 5 seconds to wait the mdlog to be flushed by the MDS's tick thread periodically. This patch will trigger to flush the mdlog in the relevant and auth MDSes to which the in-flight requests are sent just before waiting the unsafe requests to finish. Signed-off-by: Xiubo Li --- fs/ceph/caps.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index c6a3352a4d52..4b966c29d9b5 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2286,6 +2286,7 @@ static int caps_are_flushed(struct inode *inode, u64 flush_tid) */ static int unsafe_request_wait(struct inode *inode) { + struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_mds_request *req1 = NULL, *req2 = NULL; int ret, err = 0; @@ -2305,6 +2306,82 @@ static int unsafe_request_wait(struct inode *inode) } spin_unlock(&ci->i_unsafe_lock); + /* + * Trigger to flush the journal logs in all the relevant MDSes + * manually, or in the worst case we must wait at most 5 seconds + * to wait the journal logs to be flushed by the MDSes periodically. + */ + if (req1 || req2) { + struct ceph_mds_session **sessions = NULL; + struct ceph_mds_session *s; + struct ceph_mds_request *req; + unsigned int max; + int i; + + /* + * The mdsc->max_sessions is unlikely to be changed + * mostly, here we will retry it by reallocating the + * sessions arrary memory to get rid of the mdsc->mutex + * lock. + */ +retry: + max = mdsc->max_sessions; + sessions = krealloc(sessions, max * sizeof(s), __GFP_ZERO); + if (!sessions) { + err = -ENOMEM; + goto out; + } + spin_lock(&ci->i_unsafe_lock); + if (req1) { + list_for_each_entry(req, &ci->i_unsafe_dirops, + r_unsafe_dir_item) { + s = req->r_session; + if (unlikely(s->s_mds > max)) { + spin_unlock(&ci->i_unsafe_lock); + goto retry; + } + if (!sessions[s->s_mds]) { + s = ceph_get_mds_session(s); + sessions[s->s_mds] = s; + } + } + } + if (req2) { + list_for_each_entry(req, &ci->i_unsafe_iops, + r_unsafe_target_item) { + s = req->r_session; + if (unlikely(s->s_mds > max)) { + spin_unlock(&ci->i_unsafe_lock); + goto retry; + } + if (!sessions[s->s_mds]) { + s = ceph_get_mds_session(s); + sessions[s->s_mds] = s; + } + } + } + spin_unlock(&ci->i_unsafe_lock); + + /* the auth MDS */ + spin_lock(&ci->i_ceph_lock); + if (ci->i_auth_cap) { + s = ci->i_auth_cap->session; + if (!sessions[s->s_mds]) + sessions[s->s_mds] = ceph_get_mds_session(s); + } + spin_unlock(&ci->i_ceph_lock); + + /* send flush mdlog request to MDSes */ + for (i = 0; i < max; i++) { + s = sessions[i]; + if (s) { + send_flush_mdlog(s); + ceph_put_mds_session(s); + } + } + kfree(sessions); + } + dout("unsafe_request_wait %p wait on tid %llu %llu\n", inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL); if (req1) { @@ -2321,6 +2398,7 @@ static int unsafe_request_wait(struct inode *inode) err = -EIO; ceph_mdsc_put_request(req2); } +out: return err; }