From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 2431A7CA0 for ; Mon, 29 Aug 2016 13:17:50 -0500 (CDT) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay2.corp.sgi.com (Postfix) with ESMTP id EA4EC304039 for ; Mon, 29 Aug 2016 11:17:46 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id 1VD9MeNuDJplP8oI (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Mon, 29 Aug 2016 11:17:45 -0700 (PDT) Date: Mon, 29 Aug 2016 14:17:43 -0400 From: Brian Foster Subject: Re: [PATCH 3/5] xfs: don't warn on buffers not being recovered due to LSN Message-ID: <20160829181743.GB54904@bfoster.bfoster> References: <1470935467-52772-1-git-send-email-bfoster@redhat.com> <1470935467-52772-4-git-send-email-bfoster@redhat.com> <20160829012514.GL19025@dastard> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20160829012514.GL19025@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On Mon, Aug 29, 2016 at 11:25:14AM +1000, Dave Chinner wrote: > On Thu, Aug 11, 2016 at 01:11:05PM -0400, Brian Foster wrote: > > The log recovery buffer validation function is invoked in cases where a > > buffer update may be skipped due to LSN ordering. If the validation > > function happens to come across directory conversion situations (e.g., a > > dir3 block to data conversion), it may warn about seeing a buffer log > > format of one type and a buffer with a magic number of another. > > > > This warning is not valid as the buffer update is ultimately skipped. > > This is indicated by a current_lsn of NULLCOMMITLSN provided by the > > caller. As such, update xlog_recover_validate_buf_type() to only warn in > > such cases when a buffer update is expected. > > > > XXX: other issues here? better to not validate in such cases? > > I think this is OK - we really want to ensure that buffers that are > in cache always have the correct verifier attached to them. Hence if > we've read the buffer in, even if we are not modifying it because > it's more recent that what is being replayed we should still attach > the verifiers to it. > > If it changes type due to later recovery replay, we'll change the > verifier appropriately at that point. > Sounds good, thanks for commenting on this. > > @@ -2557,6 +2542,16 @@ xlog_recover_validate_buf_type( > > xfs_blft_from_flags(buf_f)); > > break; > > } > > + > > + /* > > + * A NULL current LSN indicates the buffer update is skipped due to LSN > > + * ordering. Don't warn in such cases, we skip the update for a reason > > + * (it's no longer valid)! > > + */ > > I read that the first time as "we skip the update for a reason that > is no longer valid" :P > Heh, Ok. > perhaps rework this to make it clear what is being referred to here. > e.g. No need to warn if the the buffer contents are more recent > that this recovery item and hence recovery did not modify the > buffer. > Yeah, I'll try to make that more clear. Brian > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs