linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Christoph Lameter <cl@linux.com>, Michal Hocko <mhocko@suse.cz>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Lai Jiangshan <jiangshanlai@gmail.com>, Shaohua Li <shli@fb.com>,
	linux-mm <linux-mm@kvack.org>
Subject: Re: [GIT PULL] workqueue fixes for v4.3-rc5
Date: Mon, 19 Oct 2015 05:51:50 +0200	[thread overview]
Message-ID: <1445226710.15861.28.camel@gmail.com> (raw)
In-Reply-To: <20151014202448.GE12799@mtj.duckdns.org>

On Wed, 2015-10-14 at 16:24 -0400, Tejun Heo wrote:

> But in terms of API consistency, it sucks to have queue_work()
> guarantee local queueing but not queue_delayed_work().  The ideal
> situation would be updating both so that neither guarantees.

You don't have to change anything to have neither guarantee local
queueing.  Called from a preemptible context, local means any CPU in
->cpus_allowed... which makes WORK_CPU_UNBOUND mean what one would
imagine WORK_CPU_UNBOUND to mean, not bound to any particular cpu.

      sh-16017   3.N.. 1510500545us : queue_work_on: golly, migrated cpu7 -> cpu3 -- target cpu8
      sh-16017   3.N.. 1510500550us : <stack trace>
 => tty_flip_buffer_push
 => pty_write
 => n_tty_write
 => tty_write
 => __vfs_write
 => vfs_write
 => SyS_write
 => entry_SYSCALL_64_fastpath

That was with a udelay(100) prior to disabling interrupts, but that just
makes it easier.

	-Mike

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2015-10-19  3:51 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20151013214952.GB23106@mtj.duckdns.org>
2015-10-14 16:30 ` Linus Torvalds
2015-10-14 16:57   ` Tejun Heo
2015-10-14 17:36     ` Linus Torvalds
2015-10-14 17:57       ` Christoph Lameter
2015-10-14 18:37         ` Linus Torvalds
2015-10-14 18:58           ` Christoph Lameter
2015-10-14 19:01           ` Linus Torvalds
2015-10-14 19:02       ` Tejun Heo
2015-10-14 19:16         ` Linus Torvalds
2015-10-14 19:38           ` Tejun Heo
2015-10-14 20:10             ` Linus Torvalds
2015-10-14 20:24               ` Tejun Heo
2015-10-19  3:51                 ` Mike Galbraith [this message]
2015-10-16 19:51               ` [PATCH] vmstat_update: ensure work remains on the same core Chris Metcalf
2015-10-16 19:54                 ` Linus Torvalds
2015-10-14 18:03   ` [GIT PULL] workqueue fixes for v4.3-rc5 Christoph Lameter
2015-10-14 18:40     ` Linus Torvalds
2015-10-14 18:59       ` Christoph Lameter
2015-10-14 19:10         ` Linus Torvalds

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=1445226710.15861.28.camel@gmail.com \
    --to=umgwanakikbuti@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=cl@linux.com \
    --cc=jiangshanlai@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.cz \
    --cc=shli@fb.com \
    --cc=tj@kernel.org \
    --cc=torvalds@linux-foundation.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