From: Andi Kleen <andi@firstfloor.org>
To: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Andi Kleen <andi@firstfloor.org>,
tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
peterz@infradead.org, akpm@linux-foundation.org,
andi.kleen@intel.com, rob@landley.net, viro@zeniv.linux.org.uk,
oleg@redhat.com, gnomes@lxorguk.ukuu.org.uk, riel@redhat.com,
snorcht@gmail.com, dhowells@redhat.com, luto@amacapital.net,
daeseok.youn@gmail.com, ebiederm@xmission.com,
linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH v2] Pre-emption control for userspace
Date: Tue, 25 Mar 2014 20:47:24 +0100 [thread overview]
Message-ID: <20140325194724.GV22728@two.firstfloor.org> (raw)
In-Reply-To: <5331CF58.8000909@oracle.com>
On Tue, Mar 25, 2014 at 12:47:52PM -0600, Khalid Aziz wrote:
> I am not sure if it would be practical and useful to integrate this
> into any of the standard locking interfaces, but I have not looked
> into it much either. My initial intent is to let individual apps
> decide if they could benefit from this interface and code it in if
> so since the interface is meant to be very simple. Do you see any of
> the standard locking interfaces where it would make sense to
> integrate this feature in, or are you thinking of creating a new
> interface?
It would probably make sense to use by default with glibc adaptive mutexes.
> I am reluctant to make it too big since reading larger quantities
> from userspace will take longer and start to impact performance.
> Keeping shared data limited to 32-bits allows us to move it between
> userspace and kernel with one instruction.
You don't need to read/write more. Just reserve more so that it
can be sensibly extended later.
The feature bits would only need to be written once when it is set up.
-Andi
--
ak@linux.intel.com -- Speaking for myself only.
next prev parent reply other threads:[~2014-03-25 19:47 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-03 18:07 [RFC] [PATCH] Pre-emption control for userspace Khalid Aziz
2014-03-03 21:51 ` Davidlohr Bueso
2014-03-03 23:29 ` Khalid Aziz
2014-03-04 13:56 ` Oleg Nesterov
2014-03-04 17:44 ` Khalid Aziz
2014-03-04 18:38 ` Al Viro
2014-03-04 19:01 ` Khalid Aziz
2014-03-04 19:03 ` Oleg Nesterov
2014-03-04 20:14 ` Khalid Aziz
2014-03-05 14:38 ` Oleg Nesterov
2014-03-05 16:12 ` Oleg Nesterov
2014-03-05 17:10 ` Khalid Aziz
2014-03-04 21:12 ` H. Peter Anvin
2014-03-04 21:39 ` Khalid Aziz
2014-03-04 22:23 ` One Thousand Gnomes
2014-03-04 22:44 ` Khalid Aziz
2014-03-05 0:39 ` Thomas Gleixner
2014-03-05 0:51 ` Andi Kleen
2014-03-05 11:10 ` Peter Zijlstra
2014-03-05 17:29 ` Khalid Aziz
2014-03-05 19:58 ` Khalid Aziz
2014-03-06 9:57 ` Peter Zijlstra
2014-03-06 16:08 ` Khalid Aziz
2014-03-06 11:14 ` Thomas Gleixner
2014-03-06 16:32 ` Khalid Aziz
2014-03-05 14:54 ` Oleg Nesterov
2014-03-05 15:56 ` Andi Kleen
2014-03-05 16:36 ` Oleg Nesterov
2014-03-05 17:22 ` Khalid Aziz
2014-03-05 23:13 ` David Lang
2014-03-05 23:48 ` Khalid Aziz
2014-03-05 23:56 ` H. Peter Anvin
2014-03-06 0:02 ` Khalid Aziz
2014-03-06 0:13 ` H. Peter Anvin
2014-03-05 23:59 ` David Lang
2014-03-06 0:17 ` Khalid Aziz
2014-03-06 0:36 ` David Lang
2014-03-06 1:22 ` Khalid Aziz
2014-03-06 14:23 ` David Lang
2014-03-06 12:13 ` Kevin Easton
2014-03-06 13:59 ` Peter Zijlstra
2014-03-06 22:41 ` Andi Kleen
2014-03-06 14:25 ` David Lang
2014-03-06 16:12 ` Khalid Aziz
2014-03-06 13:24 ` Rasmus Villemoes
2014-03-06 13:34 ` Peter Zijlstra
2014-03-06 13:45 ` Rasmus Villemoes
2014-03-06 14:02 ` Peter Zijlstra
2014-03-06 14:33 ` Thomas Gleixner
2014-03-06 14:34 ` H. Peter Anvin
2014-03-06 14:04 ` Thomas Gleixner
2014-03-25 17:17 ` [PATCH v2] " Khalid Aziz
2014-03-25 17:44 ` Andrew Morton
2014-03-25 17:56 ` Khalid Aziz
2014-03-25 18:14 ` Andrew Morton
2014-03-25 17:46 ` Oleg Nesterov
2014-03-25 17:59 ` Khalid Aziz
2014-03-25 18:20 ` Andi Kleen
2014-03-25 18:47 ` Khalid Aziz
2014-03-25 19:47 ` Andi Kleen [this message]
2014-03-25 18:59 ` Eric W. Biederman
2014-03-25 19:15 ` Khalid Aziz
2014-03-25 20:31 ` Eric W. Biederman
2014-03-25 21:37 ` Khalid Aziz
2014-03-26 6:03 ` Mike Galbraith
2014-03-25 23:01 ` [RFC] [PATCH] " Davidlohr Bueso
2014-03-25 23:29 ` Khalid Aziz
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