From: Michal Hocko <mhocko@kernel.org>
To: Brian Foster <bfoster@redhat.com>
Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Dave Chinner <david@fromorbit.com>,
"Theodore Ts'o" <tytso@mit.edu>, Chris Mason <clm@fb.com>,
David Sterba <dsterba@suse.cz>, Jan Kara <jack@suse.cz>,
ceph-devel@vger.kernel.org, cluster-devel@redhat.com,
linux-nfs@vger.kernel.org, logfs@logfs.org,
linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org,
linux-btrfs@vger.kernel.org, linux-mtd@lists.infradead.org,
reiserfs-devel@vger.kernel.org,
linux-ntfs-dev@lists.sourceforge.net,
linux-f2fs-devel@lists.sourceforge.net,
linux-afs@lists.infradead.org,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/9 v2] xfs: introduce and use KM_NOLOCKDEP to silence reclaim lockdep false positives
Date: Fri, 16 Dec 2016 23:01:21 +0100 [thread overview]
Message-ID: <20161216220121.GC7645@dhcp22.suse.cz> (raw)
In-Reply-To: <20161216163749.GE8447@bfoster.bfoster>
On Fri 16-12-16 11:37:50, Brian Foster wrote:
> On Fri, Dec 16, 2016 at 04:40:41PM +0100, Michal Hocko wrote:
> > Updated patch after Mike noticed a BUG_ON when KM_NOLOCKDEP is used.
> > ---
> > From 1497e713e11639157aef21cae29052cb3dc7ab44 Mon Sep 17 00:00:00 2001
> > From: Michal Hocko <mhocko@suse.com>
> > Date: Thu, 15 Dec 2016 13:06:43 +0100
> > Subject: [PATCH] xfs: introduce and use KM_NOLOCKDEP to silence reclaim
> > lockdep false positives
> >
> > Now that the page allocator offers __GFP_NOLOCKDEP let's introduce
> > KM_NOLOCKDEP alias for the xfs allocation APIs. While we are at it
> > also change KM_NOFS users introduced by b17cb364dbbb ("xfs: fix missing
> > KM_NOFS tags to keep lockdep happy") and use the new flag for them
> > instead. There is really no reason to make these allocations contexts
> > weaker just because of the lockdep which even might not be enabled
> > in most cases.
> >
>
> Hi Michal,
>
> I haven't gone back to fully grok b17cb364dbbb ("xfs: fix missing
> KM_NOFS tags to keep lockdep happy"), so I'm not really familiar with
> the original problem. FWIW, there was another KM_NOFS instance added by
> that commit in xlog_cil_prepare_log_vecs() that is now in
> xlog_cil_alloc_shadow_bufs(). Perhaps Dave can confirm whether the
> original issue still applies..?
Yes, I've noticed that but the reworked code looked sufficiently
different that I didn't dare to simply convert it.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2016-12-16 22:01 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-15 14:07 [PATCH 0/9 v2] scope GFP_NOFS api Michal Hocko
2016-12-15 14:07 ` [PATCH 1/9] lockdep: allow to disable reclaim lockup detection Michal Hocko
2016-12-15 14:07 ` [PATCH 2/9] xfs: introduce and use KM_NOLOCKDEP to silence reclaim lockdep false positives Michal Hocko
2016-12-16 15:40 ` [PATCH 2/9 v2] " Michal Hocko
2016-12-16 16:37 ` Brian Foster
2016-12-16 22:01 ` Michal Hocko [this message]
2016-12-19 21:24 ` [PATCH 2/9] " Dave Chinner
2016-12-19 22:06 ` Darrick J. Wong
2016-12-20 21:39 ` Dave Chinner
2016-12-20 8:38 ` Michal Hocko
2016-12-15 14:07 ` [PATCH 3/9] xfs: abstract PF_FSTRANS to PF_MEMALLOC_NOFS Michal Hocko
2016-12-16 16:38 ` Brian Foster
2016-12-15 14:07 ` [PATCH 4/9] mm: introduce memalloc_nofs_{save,restore} API Michal Hocko
2016-12-15 14:07 ` [PATCH 5/9] xfs: use memalloc_nofs_{save,restore} instead of memalloc_noio* Michal Hocko
2016-12-16 16:38 ` Brian Foster
2016-12-16 22:00 ` [PATCH 5/9 v2] " Michal Hocko
2016-12-15 14:07 ` [PATCH 6/9] jbd2: mark the transaction context with the scope GFP_NOFS context Michal Hocko
2016-12-16 8:39 ` Jan Kara
2016-12-15 14:07 ` [PATCH 7/9] jbd2: make the whole kjournald2 kthread NOFS safe Michal Hocko
2016-12-16 8:40 ` Jan Kara
2016-12-15 14:07 ` [PATCH 8/9] Revert "ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp" Michal Hocko
2016-12-16 8:41 ` Jan Kara
2016-12-15 14:07 ` [PATCH 9/9] Revert "ext4: fix wrong gfp type under transaction" Michal Hocko
2016-12-16 8:43 ` Jan Kara
2016-12-16 12:46 ` [DEBUG PATCH 0/2] debug explicit GFP_NO{FS,IO} usage from the scope context Michal Hocko
2016-12-16 12:46 ` [DEBUG PATCH 1/2] mm, debug: report when GFP_NO{FS,IO} is used explicitly from memalloc_no{fs,io}_{save,restore} context Michal Hocko
2016-12-16 12:46 ` [DEBUG PATCH 2/2] silent warnings which we cannot do anything about Michal Hocko
2016-12-16 15:05 ` [PATCH 0/9 v2] scope GFP_NOFS api Mike Galbraith
2016-12-16 15:35 ` Michal Hocko
2016-12-16 16:27 ` Mike Galbraith
2016-12-19 9:25 ` Jan Kara
2016-12-22 9:38 ` Michal Hocko
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