From: Oleg Nesterov <oleg@redhat.com>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>,
linux-kernel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Lai Jiangshan <laijs@cn.fujitsu.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Steven Rostedt <rostedt@goodmis.org>,
Alasdair G Kergon <agk@redhat.com>,
Arjan van de Ven <arjan@infradead.org>
Subject: Re: [RFC v2][PATCH] create workqueue threads only when needed
Date: Thu, 29 Jan 2009 05:58:48 +0100 [thread overview]
Message-ID: <20090129045848.GB5231@redhat.com> (raw)
In-Reply-To: <20090128233112.GB7631@nowhere>
On 01/29, Frederic Weisbecker wrote:
>
> I was about to retry the same approach but through async functions (kernel/async.c)
> which would have solved the possible deadlock you described and would have made
> the synchronizations easier.
>
> But actually this is only a half solution:
>
> Pointless workqueues stay pointless, even if they don't appear before they run once.
> And moreover this is hiding the real problem: parts of the kernel use dedicated workqueues
> while kevent is sufficient most of the time.
>
> And if there are problems with using the workqueues, because of deadlocks or slow
> works, async functions are a good solution.
Completely agreed.
And. Even if some subsystem really needs its own workqueue, probably it
can use the single-threaded one, but we have a lot of multithreaded wqs.
Oleg.
prev parent reply other threads:[~2009-01-29 5:02 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-28 0:27 [RFC v2][PATCH] create workqueue threads only when needed Frederic Weisbecker
2009-01-28 3:02 ` Oleg Nesterov
2009-01-28 8:15 ` Peter Zijlstra
2009-01-28 11:33 ` Frédéric Weisbecker
2009-01-28 11:24 ` Frédéric Weisbecker
2009-01-28 23:31 ` Frederic Weisbecker
2009-01-29 4:58 ` Oleg Nesterov [this message]
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=20090129045848.GB5231@redhat.com \
--to=oleg@redhat.com \
--cc=a.p.zijlstra@chello.nl \
--cc=agk@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=arjan@infradead.org \
--cc=fweisbec@gmail.com \
--cc=laijs@cn.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rostedt@goodmis.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