From: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
To: Christoph Lameter <clameter-sJ/iWh9BUns@public.gmane.org>
Cc: Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>,
"Luck, Tony" <tony.luck-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
linux-arch-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: What if a TLB flush needed to sleep?
Date: Thu, 27 Mar 2008 14:20:52 +0100 [thread overview]
Message-ID: <1206624052.8514.570.camel@twins> (raw)
In-Reply-To: <Pine.LNX.4.64.0803261817110.1115-RYO/mD75kfhx2SFC9UQUAuF7EQX82lMiAL8bYrjMMd8@public.gmane.org>
On Wed, 2008-03-26 at 18:19 -0700, Christoph Lameter wrote:
> On Wed, 26 Mar 2008, Thomas Gleixner wrote:
>
> > Please use a mutex, not a semaphore. semaphores should only be used
> > when you need a counting sempahore.
>
> Seems that mutexes are mainly useful for 2 processor systems since they
> do not allow concurrent read sections. We want multiple processors able
> to reclaim pages within the same vma or file concurrently. This means
> processors need to be able to concurrently walk potentially long lists of
> vmas.
confusion between semaphores and rwsems
WARNING: multiple messages have this Message-ID (diff)
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
"Luck, Tony" <tony.luck@intel.com>,
linux-arch@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org
Subject: Re: What if a TLB flush needed to sleep?
Date: Thu, 27 Mar 2008 14:20:52 +0100 [thread overview]
Message-ID: <1206624052.8514.570.camel@twins> (raw)
Message-ID: <20080327132052.RaoLdB3GENAOa4uKqjuqZ4HDMvbZ0A3HWiFEqiWrxSc@z> (raw)
In-Reply-To: <Pine.LNX.4.64.0803261817110.1115@schroedinger.engr.sgi.com>
On Wed, 2008-03-26 at 18:19 -0700, Christoph Lameter wrote:
> On Wed, 26 Mar 2008, Thomas Gleixner wrote:
>
> > Please use a mutex, not a semaphore. semaphores should only be used
> > when you need a counting sempahore.
>
> Seems that mutexes are mainly useful for 2 processor systems since they
> do not allow concurrent read sections. We want multiple processors able
> to reclaim pages within the same vma or file concurrently. This means
> processors need to be able to concurrently walk potentially long lists of
> vmas.
confusion between semaphores and rwsems
next prev parent reply other threads:[~2008-03-27 13:20 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-25 20:49 What if a TLB flush needed to sleep? Luck, Tony
2008-03-25 20:49 ` Luck, Tony
[not found] ` <1FE6DD409037234FAB833C420AA843ECE9DF60-7XlYjKTK0pM64kNsxIetb7fspsVTdybXVpNB7YpNyf8@public.gmane.org>
2008-03-25 21:47 ` Alan Cox
2008-03-25 21:47 ` Alan Cox
2008-03-26 12:32 ` Matthew Wilcox
2008-03-26 12:32 ` Matthew Wilcox
[not found] ` <20080326123239.GG16721-6jwH94ZQLHl74goWV3ctuw@public.gmane.org>
2008-03-26 20:29 ` Luck, Tony
2008-03-26 20:29 ` Luck, Tony
[not found] ` <1FE6DD409037234FAB833C420AA843ECE9EB1C-7XlYjKTK0pM64kNsxIetb7fspsVTdybXVpNB7YpNyf8@public.gmane.org>
2008-03-27 8:09 ` Jens Axboe
2008-03-27 8:09 ` Jens Axboe
2008-03-27 14:15 ` down_spin() implementation Matthew Wilcox
2008-03-27 14:15 ` Matthew Wilcox
[not found] ` <20080327141508.GL16721-6jwH94ZQLHl74goWV3ctuw@public.gmane.org>
2008-03-28 0:01 ` Nick Piggin
2008-03-28 0:01 ` Nick Piggin
[not found] ` <200803281101.25037.nickpiggin-/E1597aS9LT0CCvOHzKKcA@public.gmane.org>
2008-03-28 12:45 ` Matthew Wilcox
2008-03-28 12:45 ` Matthew Wilcox
[not found] ` <20080328124517.GQ16721-6jwH94ZQLHl74goWV3ctuw@public.gmane.org>
2008-03-28 21:16 ` Luck, Tony
2008-03-28 21:16 ` Luck, Tony
[not found] ` <1FE6DD409037234FAB833C420AA843ECF237C0-7XlYjKTK0pM64kNsxIetb7fspsVTdybXVpNB7YpNyf8@public.gmane.org>
2008-03-28 23:48 ` Arnd Bergmann
2008-03-28 23:48 ` Arnd Bergmann
2008-03-29 1:04 ` Nick Piggin
2008-03-29 1:04 ` Nick Piggin
2008-03-28 4:51 ` Stephen Rothwell
2008-03-28 4:51 ` Stephen Rothwell
[not found] ` <20080328155107.e9d8866c.sfr-3FnU+UHB4dNDw9hX6IcOSA@public.gmane.org>
2008-03-28 5:03 ` Nick Piggin
2008-03-28 5:03 ` Nick Piggin
[not found] ` <200803281603.34134.nickpiggin-/E1597aS9LT0CCvOHzKKcA@public.gmane.org>
2008-03-28 12:46 ` Matthew Wilcox
2008-03-28 12:46 ` Matthew Wilcox
2008-03-28 12:51 ` Jens Axboe
2008-03-28 12:51 ` Jens Axboe
[not found] ` <20080328125104.GK12346-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org>
2008-03-28 13:17 ` Matthew Wilcox
2008-03-28 13:17 ` Matthew Wilcox
[not found] ` <20080328131750.GT16721-6jwH94ZQLHl74goWV3ctuw@public.gmane.org>
2008-03-28 13:24 ` Jens Axboe
2008-03-28 13:24 ` Jens Axboe
2008-03-26 19:25 ` What if a TLB flush needed to sleep? Christoph Lameter
2008-03-26 19:25 ` Christoph Lameter
[not found] ` <Pine.LNX.4.64.0803261222090.31000-RYO/mD75kfhx2SFC9UQUAuF7EQX82lMiAL8bYrjMMd8@public.gmane.org>
2008-03-26 20:29 ` Thomas Gleixner
2008-03-26 20:29 ` Thomas Gleixner
[not found] ` <alpine.LFD.1.00.0803262121440.3781-dbfLifZv8x0yMciVaGeJ0d53zsg1cpMQ@public.gmane.org>
2008-03-27 1:19 ` Christoph Lameter
2008-03-27 1:19 ` Christoph Lameter
[not found] ` <Pine.LNX.4.64.0803261817110.1115-RYO/mD75kfhx2SFC9UQUAuF7EQX82lMiAL8bYrjMMd8@public.gmane.org>
2008-03-27 13:20 ` Peter Zijlstra [this message]
2008-03-27 13:20 ` Peter Zijlstra
2008-03-27 18:44 ` Christoph Lameter
2008-03-27 18:44 ` Christoph Lameter
[not found] ` <Pine.LNX.4.64.0803271143540.7531-RYO/mD75kfhx2SFC9UQUAuF7EQX82lMiAL8bYrjMMd8@public.gmane.org>
2008-03-28 9:59 ` Peter Zijlstra
2008-03-28 9:59 ` Peter Zijlstra
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