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 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 E0D7DC43219 for ; Thu, 25 Apr 2019 15:02:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0856F2084F for ; Thu, 25 Apr 2019 15:02:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728543AbfDYPCW (ORCPT ); Thu, 25 Apr 2019 11:02:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50647 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726074AbfDYPCV (ORCPT ); Thu, 25 Apr 2019 11:02:21 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AAA5C30A818F; Thu, 25 Apr 2019 15:02:21 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-121-98.rdu2.redhat.com [10.10.121.98]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4DF561018A11; Thu, 25 Apr 2019 15:02:20 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 4/6] afs: Use RCU inode cache search for callback resolution [ver #2] From: David Howells To: viro@zeniv.linux.org.uk Cc: linux-afs@lists.infradead.org, dhowells@redhat.com, linux-afs@lists.infradead.org, linux-ext4@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 25 Apr 2019 16:02:19 +0100 Message-ID: <155620453952.4720.15231543377694604682.stgit@warthog.procyon.org.uk> In-Reply-To: <155620449631.4720.8762546550728087460.stgit@warthog.procyon.org.uk> References: <155620449631.4720.8762546550728087460.stgit@warthog.procyon.org.uk> User-Agent: StGit/unknown-version MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.44]); Thu, 25 Apr 2019 15:02:21 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Search the inode cache under "RCU conditions" when trying to find a vnode to break the callback on. We don't want to be taking the icache lock if we can avoid it. Signed-off-by: David Howells cc: linux-afs@lists.infradead.org --- fs/afs/callback.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/afs/callback.c b/fs/afs/callback.c index 128f2dbe256a..3d0280d4fbf0 100644 --- a/fs/afs/callback.c +++ b/fs/afs/callback.c @@ -251,6 +251,7 @@ static void afs_break_one_callback(struct afs_server *server, struct afs_vnode *vnode; struct inode *inode; + rcu_read_lock(); read_lock(&server->cb_break_lock); hlist_for_each_entry(vi, &server->cb_volumes, srv_link) { if (vi->vid < fid->vid) @@ -284,18 +285,23 @@ static void afs_break_one_callback(struct afs_server *server, } else { data.volume = NULL; data.fid = *fid; - inode = ilookup5_nowait(cbi->sb, fid->vnode, - afs_iget5_test, &data); + + /* See if we can find a matching inode - even an I_NEW + * inode needs to be marked as it can have its callback + * broken before we finish setting up the local inode. + */ + inode = find_inode_rcu(cbi->sb, fid->vnode, + afs_iget5_test, &data); if (inode) { vnode = AFS_FS_I(inode); afs_break_callback(vnode); - iput(inode); } } } out: read_unlock(&server->cb_break_lock); + rcu_read_unlock(); } /*