From patchwork Tue May 26 18:53:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 225193 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 D22D7C433E0 for ; Tue, 26 May 2020 19:32:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A891C20849 for ; Tue, 26 May 2020 19:32:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590521574; bh=DYY57umynyFAZK/twDxMmZVr1Hq81x9GD9DqV30xJ0g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NbVJEurD2FZaOEv+pRHgKvLU8VWKc+Zv0mF2A58ETWJWs4E/w5HGs94BCXzBWxEhG 5/c8awcXcoXpHKG3Ef4ccpNwXit0u9JMRlax+FyBeFeTc6lT5zM4vyfoI6eowYM3Qw LAL4DAXEzeDjL1ynWQ/gp/EbeBkRLFmG/h0k3Zvg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389969AbgEZS46 (ORCPT ); Tue, 26 May 2020 14:56:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:50016 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389982AbgEZS44 (ORCPT ); Tue, 26 May 2020 14:56:56 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9DB4A20870; Tue, 26 May 2020 18:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519416; bh=DYY57umynyFAZK/twDxMmZVr1Hq81x9GD9DqV30xJ0g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K98ZDr4/O4fbhbBB9CNtMYtY8VCQPlMO8+BmhcRCLsnjvVXtusegq3y7km+FelGRI v+emOVPGKocSxm5GLzi5cfqR+Rrx9YdfnL4Bjp2cQhoV2Q7/yJP8kK0FQXekuG35j1 K4k5rHdbLNCE4iw0iSZFZxJrW9VN5FzIwASZHxa4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bob Peterson , Sasha Levin Subject: [PATCH 4.4 61/65] Revert "gfs2: Dont demote a glock until its revokes are written" Date: Tue, 26 May 2020 20:53:20 +0200 Message-Id: <20200526183928.499403894@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183905.988782958@linuxfoundation.org> References: <20200526183905.988782958@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Bob Peterson [ Upstream commit b14c94908b1b884276a6608dea3d0b1b510338b7 ] This reverts commit df5db5f9ee112e76b5202fbc331f990a0fc316d6. This patch fixes a regression: patch df5db5f9ee112 allowed function run_queue() to bypass its call to do_xmote() if revokes were queued for the glock. That's wrong because its call to do_xmote() is what is responsible for calling the go_sync() glops functions to sync both the ail list and any revokes queued for it. By bypassing the call, gfs2 could get into a stand-off where the glock could not be demoted until its revokes are written back, but the revokes would not be written back because do_xmote() was never called. It "sort of" works, however, because there are other mechanisms like the log flush daemon (logd) that can sync the ail items and revokes, if it deems it necessary. The problem is: without file system pressure, it might never deem it necessary. Signed-off-by: Bob Peterson Signed-off-by: Sasha Levin --- fs/gfs2/glock.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index f80ffccb0316..1eb737c466dd 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -541,9 +541,6 @@ __acquires(&gl->gl_lockref.lock) goto out_unlock; if (nonblock) goto out_sched; - smp_mb(); - if (atomic_read(&gl->gl_revokes) != 0) - goto out_sched; set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); gl->gl_target = gl->gl_demote_state;