From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>,
linux-xfs@vger.kernel.org, linux-mm@kvack.org,
linux-fsdevel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
Will Deacon <will@kernel.org>,
"Paul E. McKenney" <paulmck@kernel.org>
Subject: Re: [PATCH 25/26] xfs: rework unreferenced inode lookups
Date: Fri, 11 Oct 2019 15:39:26 +0200 [thread overview]
Message-ID: <20191011133926.GY2328@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20191011125522.GA13167@infradead.org>
On Fri, Oct 11, 2019 at 05:55:22AM -0700, Christoph Hellwig wrote:
> On Wed, Oct 09, 2019 at 02:21:23PM +1100, Dave Chinner wrote:
> > @@ -131,6 +132,7 @@ xfs_inode_free(
> > * free state. The ip->i_flags_lock provides the barrier against lookup
> > * races.
> > */
> > + xfs_ilock(ip, XFS_ILOCK_EXCL);
>
> This introduceѕ a non-owner unlock of an exclusively held rwsem. As-is
> this will make lockdep very unhappy. We have a non-owner unlock version
> of up_read, but not of up_write currently. I'm also not sure if those
> are allowed from RCU callback, which IIRC can run from softirq context.
>
> That being said this scheme of only unlocking the inode in the rcu free
> callback makes totaly sense to me, so I wish we can accomodate it
> somehow.
I'm thinking that, barring the little issue of not actually having the
function, up_write_non_owner() should work from RCU callback context.
That is, I don't see rwsem_wake() do anything not allowed there.
next prev parent reply other threads:[~2019-10-11 13:39 UTC|newest]
Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-09 3:20 [PATCH V2 00/26] mm, xfs: non-blocking inode reclaim Dave Chinner
2019-10-09 3:20 ` [PATCH 01/26] xfs: Lower CIL flush limit for large logs Dave Chinner
2019-10-11 12:39 ` Brian Foster
2019-10-30 17:08 ` Darrick J. Wong
2019-10-09 3:21 ` [PATCH 02/26] xfs: Throttle commits on delayed background CIL push Dave Chinner
2019-10-11 12:38 ` Brian Foster
2019-10-09 3:21 ` [PATCH 03/26] xfs: don't allow log IO to be throttled Dave Chinner
2019-10-11 9:35 ` Christoph Hellwig
2019-10-11 12:39 ` Brian Foster
2019-10-30 17:14 ` Darrick J. Wong
2019-10-09 3:21 ` [PATCH 04/26] xfs: Improve metadata buffer reclaim accountability Dave Chinner
2019-10-11 12:39 ` Brian Foster
2019-10-11 12:57 ` Christoph Hellwig
2019-10-11 23:14 ` Dave Chinner
2019-10-11 23:13 ` Dave Chinner
2019-10-12 12:05 ` Brian Foster
2019-10-13 3:14 ` Dave Chinner
2019-10-14 13:05 ` Brian Foster
2019-10-30 17:25 ` Darrick J. Wong
2019-10-30 21:43 ` Dave Chinner
2019-10-31 3:06 ` Darrick J. Wong
2019-10-31 20:50 ` Dave Chinner
2019-10-31 21:05 ` Darrick J. Wong
2019-10-31 21:22 ` Christoph Hellwig
2019-11-03 21:26 ` Dave Chinner
2019-11-04 23:08 ` Darrick J. Wong
2019-10-09 3:21 ` [PATCH 05/26] xfs: correctly acount for reclaimable slabs Dave Chinner
2019-10-11 12:39 ` Brian Foster
2019-10-30 17:16 ` Darrick J. Wong
2019-10-09 3:21 ` [PATCH 06/26] xfs: synchronous AIL pushing Dave Chinner
2019-10-11 9:42 ` Christoph Hellwig
2019-10-11 12:40 ` Brian Foster
2019-10-11 23:15 ` Dave Chinner
2019-10-09 3:21 ` [PATCH 07/26] xfs: tail updates only need to occur when LSN changes Dave Chinner
2019-10-11 9:50 ` Christoph Hellwig
2019-10-11 12:40 ` Brian Foster
2019-10-09 3:21 ` [PATCH 08/26] mm: directed shrinker work deferral Dave Chinner
2019-10-14 8:46 ` Christoph Hellwig
2019-10-14 13:06 ` Brian Foster
2019-10-18 7:59 ` Dave Chinner
2019-10-09 3:21 ` [PATCH 09/26] shrinkers: use defer_work for GFP_NOFS sensitive shrinkers Dave Chinner
2019-10-09 3:21 ` [PATCH 10/26] mm: factor shrinker work calculations Dave Chinner
2019-10-09 3:21 ` [PATCH 11/26] shrinker: defer work only to kswapd Dave Chinner
2019-10-09 3:21 ` [PATCH 12/26] shrinker: clean up variable types and tracepoints Dave Chinner
2019-10-09 3:21 ` [PATCH 13/26] mm: reclaim_state records pages reclaimed, not slabs Dave Chinner
2019-10-09 3:21 ` [PATCH 14/26] mm: back off direct reclaim on excessive shrinker deferral Dave Chinner
2019-10-11 16:21 ` Matthew Wilcox
2019-10-11 23:20 ` Dave Chinner
2019-10-09 3:21 ` [PATCH 15/26] mm: kswapd backoff for shrinkers Dave Chinner
2019-10-09 3:21 ` [PATCH 16/26] xfs: synchronous AIL pushing Dave Chinner
2019-10-11 10:18 ` Christoph Hellwig
2019-10-11 15:29 ` Brian Foster
2019-10-11 23:27 ` Dave Chinner
2019-10-12 12:08 ` Brian Foster
2019-10-09 3:21 ` [PATCH 17/26] xfs: don't block kswapd in inode reclaim Dave Chinner
2019-10-11 15:29 ` Brian Foster
2019-10-09 3:21 ` [PATCH 18/26] xfs: reduce kswapd blocking on inode locking Dave Chinner
2019-10-11 10:29 ` Christoph Hellwig
2019-10-09 3:21 ` [PATCH 19/26] xfs: kill background reclaim work Dave Chinner
2019-10-11 10:31 ` Christoph Hellwig
2019-10-09 3:21 ` [PATCH 20/26] xfs: use AIL pushing for inode reclaim IO Dave Chinner
2019-10-11 17:38 ` Brian Foster
2019-10-09 3:21 ` [PATCH 21/26] xfs: remove mode from xfs_reclaim_inodes() Dave Chinner
2019-10-11 10:39 ` Christoph Hellwig
2019-10-14 13:07 ` Brian Foster
2019-10-09 3:21 ` [PATCH 22/26] xfs: track reclaimable inodes using a LRU list Dave Chinner
2019-10-11 10:42 ` Christoph Hellwig
2019-10-14 13:07 ` Brian Foster
2019-10-09 3:21 ` [PATCH 23/26] xfs: reclaim inodes from the LRU Dave Chinner
2019-10-11 10:56 ` Christoph Hellwig
2019-10-30 23:25 ` Dave Chinner
2019-10-09 3:21 ` [PATCH 24/26] xfs: remove unusued old inode reclaim code Dave Chinner
2019-10-09 3:21 ` [PATCH 25/26] xfs: rework unreferenced inode lookups Dave Chinner
2019-10-11 12:55 ` Christoph Hellwig
2019-10-11 13:39 ` Peter Zijlstra [this message]
2019-10-11 23:38 ` Dave Chinner
2019-10-14 13:07 ` Brian Foster
2019-10-17 1:24 ` Dave Chinner
2019-10-17 7:57 ` Brian Foster
2019-10-18 20:29 ` Dave Chinner
2019-10-09 3:21 ` [PATCH 26/26] xfs: use xfs_ail_push_all_sync in xfs_reclaim_inodes Dave Chinner
2019-10-11 9:55 ` Christoph Hellwig
2019-10-09 7:06 ` [PATCH V2 00/26] mm, xfs: non-blocking inode reclaim Christoph Hellwig
2019-10-11 19:03 ` Josef Bacik
2019-10-11 23:48 ` Dave Chinner
2019-10-12 0:19 ` Josef Bacik
2019-10-12 0:48 ` Dave Chinner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191011133926.GY2328@hirez.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-xfs@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=paulmck@kernel.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).