linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Hugh Dickins <hughd@google.com>
To: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Jan Kara <jack@suse.cz>,
	William Kucharski <william.kucharski@oracle.com>,
	Linux-FSDevel <linux-fsdevel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>, Christoph Hellwig <hch@lst.de>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Yang Shi <yang.shi@linux.alibaba.com>,
	dchinner@redhat.com, linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4 00/16] Overhaul multi-page lookups for THP
Date: Mon, 30 Nov 2020 11:45:46 -0800 (PST)	[thread overview]
Message-ID: <alpine.LSU.2.11.2011301109230.17996@eggly.anvils> (raw)
In-Reply-To: <20201126200703.GW4327@casper.infradead.org>

On Thu, 26 Nov 2020, Matthew Wilcox wrote:
> On Thu, Nov 26, 2020 at 11:24:59AM -0800, Hugh Dickins wrote:
> 
> > But right now it's the right fix that's important: ack to yours below.
> > 
> > I've not yet worked out the other issues I saw: will report when I have.
> > Rebooted this laptop, pretty sure it missed freeing a shmem swap entry,
> > not yet reproduced, will study the change there later, but the non-swap 
> > hang in generic/476 (later seen also in generic/112) more important.

It's been a struggle, but I do now have a version of shmem_undo_range()
that works reliably, no known bugs, with no changes to your last version
outside of shmem_undo_range().

But my testing so far has been with the initial optimization loop (of
trylocks in find_lock_entries()) "#if 0"ed out, to give the final loop
a harder time. Now I'll bring back that initial loop (maybe cleaning up
some start/end variables) and retest - hoping not to regress as I do so.

I'll send it late today: I expect I'll just send the body of
shmem_undo_range() itself, rather than a diff, since it's too confusing
to know what to diff against.  Or, maybe you now have your own improved
version, and will want me to look at yours rather than sending mine.

Andrew, if you're planning another mmotm soon, please remove/comment
mm-truncateshmem-handle-truncates-that-split-thps.patch
and any of its "fixes" as to-be-updated: all versions to date
have been too buggy to keep, and a new version will require its own
review, as you noted. I think that means you also have to remove
mm-filemap-return-only-head-pages-from-find_get_entries.patch
which I think is blameless, but may depend on it logically.

> 
> The good news is that I've sorted out the SCRATCH_DEV issue with
> running xfstests.  The bad news is that (even on an unmodified kernel),
> generic/027 takes 19 hours to run.  On xfs, it's 4 minutes.  Any idea
> why it's so slow on tmpfs?

I sent a tarball of four xfstests patches on Thursday, they're valid:
but generic/075 and generic/112, very useful for this testing, suffer
from an fsx build bug which might or might not affect you: so I'll now
reply to that mail with latest tarball.

Hugh

  reply	other threads:[~2020-11-30 19:46 UTC|newest]

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-12 21:26 Matthew Wilcox (Oracle)
2020-11-12 21:26 ` [PATCH v4 01/16] mm: Make pagecache tagged lookups return only head pages Matthew Wilcox (Oracle)
2020-11-14  9:53   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 02/16] mm/shmem: Use pagevec_lookup in shmem_unlock_mapping Matthew Wilcox (Oracle)
2020-11-14  9:53   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 03/16] mm/swap: Optimise get_shadow_from_swap_cache Matthew Wilcox (Oracle)
2020-11-14  9:53   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 04/16] mm: Add FGP_ENTRY Matthew Wilcox (Oracle)
2020-11-14 10:00   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 05/16] mm/filemap: Rename find_get_entry to mapping_get_entry Matthew Wilcox (Oracle)
2020-11-14 10:01   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 06/16] mm/filemap: Add helper for finding pages Matthew Wilcox (Oracle)
2020-11-14 10:03   ` Christoph Hellwig
2020-11-14 15:15     ` Matthew Wilcox
2020-11-12 21:26 ` [PATCH v4 07/16] mm/filemap: Add mapping_seek_hole_data Matthew Wilcox (Oracle)
2020-11-14 10:04   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 08/16] iomap: Use mapping_seek_hole_data Matthew Wilcox (Oracle)
2020-11-14 10:06   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 09/16] mm: Add and use find_lock_entries Matthew Wilcox (Oracle)
2020-11-14 10:07   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 10/16] mm: Add an 'end' parameter to find_get_entries Matthew Wilcox (Oracle)
2020-11-14 10:08   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 11/16] mm: Add an 'end' parameter to pagevec_lookup_entries Matthew Wilcox (Oracle)
2020-11-14 10:19   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 12/16] mm: Remove nr_entries parameter from pagevec_lookup_entries Matthew Wilcox (Oracle)
2020-11-14 10:19   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 13/16] mm: Pass pvec directly to find_get_entries Matthew Wilcox (Oracle)
2020-11-14 10:21   ` Christoph Hellwig
2020-11-14 15:22     ` Matthew Wilcox
2020-11-12 21:26 ` [PATCH v4 14/16] mm: Remove pagevec_lookup_entries Matthew Wilcox (Oracle)
2020-11-14 10:22   ` Christoph Hellwig
2020-11-12 21:26 ` [PATCH v4 15/16] mm/truncate,shmem: Handle truncates that split THPs Matthew Wilcox (Oracle)
2020-11-12 21:26 ` [PATCH v4 16/16] mm/filemap: Return only head pages from find_get_entries Matthew Wilcox (Oracle)
2020-11-14 10:23   ` Christoph Hellwig
2020-11-16 10:34 ` [PATCH v4 00/16] Overhaul multi-page lookups for THP Hugh Dickins
2020-11-16 15:14   ` Matthew Wilcox
2020-11-16 21:27     ` Hugh Dickins
2020-11-17 15:39   ` Matthew Wilcox
2020-11-17 16:26     ` Hugh Dickins
2020-11-17 19:15       ` Matthew Wilcox
2020-11-17 23:43         ` Matthew Wilcox
2020-11-25  2:32           ` Matthew Wilcox
2020-11-25  2:50             ` Hugh Dickins
2020-11-25  2:56               ` Hugh Dickins
2020-11-25 23:08             ` Andrew Morton
2020-11-26  0:11               ` Hugh Dickins
2020-11-26 12:15                 ` Matthew Wilcox
2020-11-26 19:24                   ` Hugh Dickins
2020-11-26 20:07                     ` Matthew Wilcox
2020-11-30 19:45                       ` Hugh Dickins [this message]
2020-12-01  4:52                         ` Hugh Dickins
     [not found]             ` <CGME20201203154604eucas1p200d001d25dd344a1dd1c7da34f35aad0@eucas1p2.samsung.com>
2020-12-03 15:46               ` Marek Szyprowski
     [not found]                 ` <CGME20201203172725eucas1p2fddec1d269c55095859d490942b78b93@eucas1p2.samsung.com>
2020-12-03 17:27                   ` Marek Szyprowski
2020-12-03 21:27                     ` Qian Cai
2020-12-03 22:19                       ` Hugh Dickins
2020-12-03 21:45                     ` Hugh Dickins
2021-02-23 22:58 ` Andrew Morton
2021-02-23 23:27   ` Matthew Wilcox

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=alpine.LSU.2.11.2011301109230.17996@eggly.anvils \
    --to=hughd@google.com \
    --cc=akpm@linux-foundation.org \
    --cc=dchinner@redhat.com \
    --cc=hannes@cmpxchg.org \
    --cc=hch@lst.de \
    --cc=jack@suse.cz \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=william.kucharski@oracle.com \
    --cc=willy@infradead.org \
    --cc=yang.shi@linux.alibaba.com \
    --subject='Re: [PATCH v4 00/16] Overhaul multi-page lookups for THP' \
    /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

This is a public inbox, see mirroring instructions
on how to clone and mirror all data and code used for this inbox