From: Mel Gorman <mgorman@techsingularity.net>
To: Doug Anderson <dianders@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Vlastimil Babka <vbabka@suse.cz>, Ying <ying.huang@intel.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
Yu Zhao <yuzhao@google.com>,
linux-fsdevel@vger.kernel.org,
Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH v2 1/4] mm/filemap: Add folio_lock_timeout()
Date: Tue, 25 Apr 2023 09:00:52 +0100 [thread overview]
Message-ID: <20230425080052.63dik4aadlrjvd2p@techsingularity.net> (raw)
In-Reply-To: <CAD=FV=XRMiDxKyLKGKL3ekk8CjRt6puT1PReD+pE21JGgF4TQw@mail.gmail.com>
On Mon, Apr 24, 2023 at 09:22:55AM -0700, Doug Anderson wrote:
> Hi,
>
> On Mon, Apr 24, 2023 at 1:22???AM Mel Gorman <mgorman@techsingularity.net> wrote:
> >
> > > @@ -1295,10 +1296,13 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr,
> > > /* Loop until we've been woken or interrupted */
> > > flags = smp_load_acquire(&wait->flags);
> > > if (!(flags & WQ_FLAG_WOKEN)) {
> > > + if (!timeout)
> > > + break;
> > > +
> >
> > An io_schedule_timeout of 0 is valid so why the special handling? It's
> > negative timeouts that cause schedule_timeout() to complain.
>
> It's not expected that the caller passes in a timeout of 0 here. The
> test here actually handles the case that the previous call to
> io_schedule_timeout() returned 0. In my patch, after the call to
> io_schedule_timeout() we unconditionally "continue" and end up back at
> the top of the loop. The next time through the loop if we don't see
> the WOKEN flag then we'll check for the two "error" conditions
> (timeout or signal pending) and break for either of them.
Ah, I see!
>
> To make it clearer, I'll add this comment for the next version:
>
> /* Break if the last io_schedule_timeout() said no time left */
Yes please.
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2023-04-25 8:00 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-21 22:12 [PATCH v2 0/4] migrate: Avoid unbounded blocks in MIGRATE_SYNC_LIGHT Douglas Anderson
2023-04-21 22:12 ` [PATCH v2 1/4] mm/filemap: Add folio_lock_timeout() Douglas Anderson
2023-04-22 5:18 ` Hillf Danton
[not found] ` <20230423081203.1812-1-hdanton@sina.com>
2023-04-23 8:35 ` Gao Xiang
2023-04-23 9:49 ` Hillf Danton
2023-04-23 10:45 ` Gao Xiang
2023-04-24 16:56 ` Doug Anderson
2023-04-25 1:09 ` Hillf Danton
2023-04-25 14:19 ` Doug Anderson
2023-04-26 4:42 ` Hillf Danton
2023-04-26 4:55 ` Doug Anderson
2023-04-26 10:09 ` Mel Gorman
2023-04-26 15:14 ` Matthew Wilcox
2023-04-26 20:46 ` Doug Anderson
2023-04-26 21:26 ` Matthew Wilcox
2023-04-26 21:39 ` Doug Anderson
2023-04-27 2:16 ` Matthew Wilcox
2023-04-27 9:48 ` Mel Gorman
2023-04-28 8:17 ` Hillf Danton
2023-04-26 15:24 ` Linus Torvalds
2023-04-23 7:50 ` Huang, Ying
2023-04-24 8:22 ` Mel Gorman
2023-04-24 16:22 ` Doug Anderson
2023-04-25 8:00 ` Mel Gorman [this message]
2023-04-21 22:12 ` [PATCH v2 2/4] buffer: Add lock_buffer_timeout() Douglas Anderson
2023-04-23 8:47 ` Huang, Ying
2023-04-21 22:12 ` [PATCH v2 3/4] migrate_pages: Don't wait forever locking pages in MIGRATE_SYNC_LIGHT Douglas Anderson
2023-04-23 7:59 ` Huang, Ying
2023-04-24 9:38 ` Mel Gorman
2023-04-21 22:12 ` [PATCH v2 4/4] migrate_pages: Don't wait forever locking buffers " Douglas Anderson
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=20230425080052.63dik4aadlrjvd2p@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=akpm@linux-foundation.org \
--cc=brauner@kernel.org \
--cc=dianders@chromium.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=vbabka@suse.cz \
--cc=viro@zeniv.linux.org.uk \
--cc=willy@infradead.org \
--cc=ying.huang@intel.com \
--cc=yuzhao@google.com \
/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).