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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 51388C76188 for ; Fri, 19 Jul 2019 14:58:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 291532173B for ; Fri, 19 Jul 2019 14:58:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728077AbfGSO6B (ORCPT ); Fri, 19 Jul 2019 10:58:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:49060 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726072AbfGSO6B (ORCPT ); Fri, 19 Jul 2019 10:58:01 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id DD106B005; Fri, 19 Jul 2019 14:57:59 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id D4E60DA7E8; Fri, 19 Jul 2019 16:58:34 +0200 (CEST) Date: Fri, 19 Jul 2019 16:58:34 +0200 From: David Sterba To: Anand Jain Cc: linux-btrfs@vger.kernel.org, g.btrfs@cobb.uk.net, calestyo@scientia.net Subject: Re: [PATCH] btrfs: ratelimit device path change info on mounted device Message-ID: <20190719145833.GL20977@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Anand Jain , linux-btrfs@vger.kernel.org, g.btrfs@cobb.uk.net, calestyo@scientia.net References: <5d8baf80-4fb3-221f-5ab4-e98a838f63e1@cobb.uk.net> <20190716135910.848-1-anand.jain@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190716135910.848-1-anand.jain@oracle.com> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Tue, Jul 16, 2019 at 09:59:10PM +0800, Anand Jain wrote: > If there are more than one path to a device, the last scanned path > will map to the mounted FS. In some Linux based os there appears to be a > system script (autofs?) which fails to notice that a device's alternative > path is already mounted, and so the change in device-path gets logged > every ~2mins whenever such a script is active. > > kernel: [33017.407252] BTRFS info (device sdc3): > device fsid 4d1ba5af-8b89-4cb5-96c6-55d1f028a202 devid 4 moved > old:/dev/mapper/cryptdata4tb--vg-backup new:/dev/dm-13 > kernel: [33017.522242] BTRFS info (device sdc3): > device fsid 4d1ba5af-8b89-4cb5-96c6-55d1f028a202 devid 4 moved > old:/dev/dm-13 new:/dev/mapper/cryptdata4tb--vg-backup > kernel: [33018.797161] BTRFS info (device sdc3): > device fsid 4d1ba5af-8b89-4cb5-96c6-55d1f028a202 devid 4 moved > old:/dev/mapper/cryptdata4tb--vg-backup new:/dev/dm-13 > kernel: [33019.061631] BTRFS info (device sdc3): > device fsid 4d1ba5af-8b89-4cb5-96c6-55d1f028a202 devid 4 moved > old:/dev/dm-13 new:/dev/mapper/cryptdata4tb--vg-backup > > Fix this by using the ratelimit printk. The ratelimiting will most certainly not stop the repeated messages, btrfs_info_rl_in_rcu uses the default settings which is to limit within 5 seconds and allow burts of 10 messages.