From patchwork Tue May 26 18:53:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 225381 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=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 AF847C433E0 for ; Tue, 26 May 2020 19:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81B3C208C3 for ; Tue, 26 May 2020 19:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519909; bh=KOOqmjkT3/NHkepUVqMyX89PGaVwj5+wi37xbhKpEEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Cf5ES8KTZ1F2rWgWsYTxd1Ut3UIJ0u5UjM3D/KLtNoqN29GWEJUUbrr9aX7zx9eEG nXNdCp51lFYjoUoKVrE4YfanRoOFgZX3w+HIhCzVCrnc1flKqzC39XeeqyGgwvi1mn QU7O2J8/v6KOgbhbff9hdA/8DxmogumH2HjgufU8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391465AbgEZTFH (ORCPT ); Tue, 26 May 2020 15:05:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:32916 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389967AbgEZTFG (ORCPT ); Tue, 26 May 2020 15:05:06 -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 661B820873; Tue, 26 May 2020 19:05:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519905; bh=KOOqmjkT3/NHkepUVqMyX89PGaVwj5+wi37xbhKpEEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qJsz0WOWI7xhqXZX0E1aNWalmXkZ4sajY0+cBz2jvTGDpYE05SyPyeoHEbkautWTu 3BxIh4BN88Gy9rwbOdwGdPq/4fXHbnZYwwArc3Pd5QA7CeUKtb6n+C22V+dKmJP5Eu PKEqIL48nj9Q+/xgA2wWcJjwgNtSqlTWod92O1gE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bob Peterson , Sasha Levin Subject: [PATCH 4.19 64/81] Revert "gfs2: Dont demote a glock until its revokes are written" Date: Tue, 26 May 2020 20:53:39 +0200 Message-Id: <20200526183934.175831135@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183923.108515292@linuxfoundation.org> References: <20200526183923.108515292@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 f8a5eef3d014..ccdd8c821abd 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -636,9 +636,6 @@ __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;