public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: William Lee Irwin III <wli@holomorphy.com>
To: Andrea Arcangeli <andrea@novell.com>
Cc: Ingo Molnar <mingo@elte.hu>,
	linux-kernel@vger.kernel.org, Andrew Morton <akpm@osdl.org>,
	Linus Torvalds <torvalds@osdl.org>,
	Arjan van de Ven <arjanv@redhat.com>,
	Lee Revell <rlrevell@joe-job.com>
Subject: Re: [patch] remove the BKL (Big Kernel Lock), this time for real
Date: Fri, 17 Sep 2004 07:18:19 -0700	[thread overview]
Message-ID: <20040917141819.GW9106@holomorphy.com> (raw)
In-Reply-To: <20040917135657.GW15426@dualathlon.random>

On Fri, Sep 17, 2004 at 06:47:37AM -0700, William Lee Irwin III wrote:
>> as the BKL is acquired before spinlocks in all instances. There are

On Fri, Sep 17, 2004 at 03:56:57PM +0200, Andrea Arcangeli wrote:
> that reinforces my argument, that's another case that can break with
> this patch.
> I don't think it has a chance to fix any bug, if something it will
> trigger some deadlock or race condition, but OTOH I agree it should work
> fine (all code I can recall by memory takes the BKL before any inner
> spinlock too, and I don't think we left anything that depends on
> smp_processor_id()), but again this is the kind of change that requires
> some testing and cannot be shipped by default in a stable tree, it
> requires config option at the very least.

But the corner cases I outlined don't exist; the case that does exist
is where the BKL is dropped by mistake by e.g. a call to a function
that may sleep. c.f. fs/fcntl.c:setfl().


-- wli

  reply	other threads:[~2004-09-17 14:22 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-09-15 15:18 [patch] remove the BKL (Big Kernel Lock), this time for real Ingo Molnar
2004-09-15 15:40 ` Linus Torvalds
2004-09-15 15:55   ` Ingo Molnar
2004-09-15 17:04     ` Ricky Beam
2004-09-15 19:39       ` Ingo Molnar
2004-09-15 18:28     ` Chris Wedgwood
2004-09-15 21:25   ` William Lee Irwin III
2004-09-17 10:39 ` Ingo Molnar
2004-09-17 12:53   ` Ingo Molnar
2004-09-17 20:56     ` Andrea Arcangeli
2004-09-18  8:02       ` Ingo Molnar
2004-09-18 23:36         ` Andrea Arcangeli
2004-09-17 13:26   ` Andrea Arcangeli
2004-09-17 13:47     ` William Lee Irwin III
2004-09-17 13:56       ` Andrea Arcangeli
2004-09-17 14:18         ` William Lee Irwin III [this message]
2004-09-17 15:16   ` Linus Torvalds
     [not found] <2EJTp-7bx-1@gated-at.bofh.it>
2004-09-15 15:46 ` Andi Kleen
2004-09-15 15:58   ` Ingo Molnar
2004-09-15 20:11   ` Ingo Molnar
2004-09-16  1:17     ` Nick Piggin
2004-09-16 14:28   ` Bill Davidsen
2004-09-16 22:29     ` Bill Huey
2004-09-16 22:40       ` David S. Miller
2004-09-16 22:51         ` Bill Huey
2004-09-16 22:54           ` David S. Miller
2004-09-16 23:01             ` Bill Huey
2004-09-16 23:33             ` William Lee Irwin III
2004-09-17  6:43           ` Ingo Molnar
2004-09-17  7:21             ` Tony Lee
  -- strict thread matches above, loose matches on Subject: below --
2004-09-18  5:44 Manfred Spraul
2004-09-18 13:09 ` Ingo Molnar

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=20040917141819.GW9106@holomorphy.com \
    --to=wli@holomorphy.com \
    --cc=akpm@osdl.org \
    --cc=andrea@novell.com \
    --cc=arjanv@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=rlrevell@joe-job.com \
    --cc=torvalds@osdl.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