From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
To: peterz@infradead.org
Cc: dvhart@linux.intel.com, david@rgmadvisors.com,
kyle@moffetthome.net, luto@mit.edu, eric.dumazet@gmail.com,
linux-kernel@vger.kernel.org, sbohrer@rgmadvisors.com,
zvonler@rgmadvisors.com, hughd@google.com, tglx@linutronix.de,
mingo@elte.hu
Subject: Re: Change in functionality of futex() system call.
Date: Fri, 10 Jun 2011 12:30:56 +0900 [thread overview]
Message-ID: <4DF18FF0.7010503@jp.fujitsu.com> (raw)
In-Reply-To: <1307642307.3941.92.camel@twins>
(2011/06/10 2:58), Peter Zijlstra wrote:
> On Thu, 2011-06-09 at 14:05 +0200, Peter Zijlstra wrote:
>> On Thu, 2011-06-09 at 20:37 +0900, KOSAKI Motohiro wrote:
>>> 1) check the pte of the target address is RW attribute.
>>> 2-1) if yes, it has no COW chance. we can safely use gup result.
>>> 2-2) if no, we have to fallback slow vma walk. maybe, it's okey.
>>> both RO mappings and COW are rare situation.
>>
>> Not so, clean file pages are RO, even if the vma is writable. We use the
>> fault to track dirty state with.
>
> Why can't something like
> http://marc.info/?l=linux-kernel&m=130737669810421 work once you restore
> the rw argument?
Yeah, I agree this is best way. Private RO mappings is not sane and no real
world users.
next prev parent reply other threads:[~2011-06-10 3:31 UTC|newest]
Thread overview: 99+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-06 14:28 Change in functionality of futex() system call David Oliver
2011-06-06 15:23 ` Eric Dumazet
2011-06-06 15:56 ` Shawn Bohrer
2011-06-06 16:11 ` Peter Zijlstra
2011-06-06 16:16 ` Peter Zijlstra
2011-06-06 16:22 ` Eric Dumazet
2011-06-06 16:29 ` Peter Zijlstra
2011-06-06 16:42 ` Eric Dumazet
2011-06-06 17:05 ` Peter Zijlstra
2011-06-06 17:11 ` Eric Dumazet
2011-06-06 17:27 ` Steven Rostedt
2011-06-06 17:56 ` Darren Hart
2011-06-06 18:23 ` Peter Zijlstra
2011-06-06 18:27 ` Eric Dumazet
2011-06-25 0:00 ` Darren Hart
2011-06-27 16:48 ` Shawn Bohrer
2011-06-06 17:53 ` Darren Hart
2011-06-06 18:11 ` Eric Dumazet
2011-06-07 3:13 ` Darren Hart
2011-06-07 3:49 ` Eric Dumazet
2011-06-07 14:44 ` Andy Lutomirski
2011-06-07 15:56 ` Darren Hart
2011-06-07 15:58 ` Eric Dumazet
2011-06-07 18:43 ` Andrew Lutomirski
2011-06-07 19:01 ` Darren Hart
2011-06-07 19:04 ` Andrew Lutomirski
2011-06-07 19:06 ` Eric Dumazet
2011-06-07 19:10 ` David Oliver
2011-06-07 19:19 ` Andrew Lutomirski
2011-06-07 19:33 ` David Oliver
2011-06-07 19:53 ` Andrew Lutomirski
2011-06-07 20:04 ` David Oliver
2011-06-07 20:12 ` Andrew Lutomirski
2011-06-07 22:26 ` Kyle Moffett
2011-06-08 15:20 ` David Oliver
2011-06-08 15:21 ` Andrew Lutomirski
2011-06-08 16:21 ` Darren Hart
2011-06-09 11:37 ` KOSAKI Motohiro
2011-06-09 12:05 ` Peter Zijlstra
2011-06-09 17:58 ` Peter Zijlstra
2011-06-10 3:30 ` KOSAKI Motohiro [this message]
2011-06-10 3:26 ` KOSAKI Motohiro
2011-06-07 18:30 ` Joel Becker
2011-06-09 12:05 ` Peter Zijlstra
2011-06-10 12:10 ` KOSAKI Motohiro
2011-06-10 17:29 ` Darren Hart
2011-06-13 2:11 ` KOSAKI Motohiro
2011-06-13 15:50 ` Darren Hart
2011-06-15 18:50 ` Shawn Bohrer
2011-06-15 18:54 ` Darren Hart
2011-06-17 13:40 ` Shawn Bohrer
2011-06-22 19:19 ` [PATCH RFC] futex: Fix regression with read only mappings Shawn Bohrer
2011-06-22 20:14 ` Darren Hart
2011-06-23 2:51 ` KOSAKI Motohiro
2011-06-23 15:26 ` Darren Hart
2011-06-23 19:49 ` Shawn Bohrer
2011-06-24 15:59 ` [PATCH v2] " Shawn Bohrer
2011-06-25 0:37 ` Darren Hart
2011-06-25 15:10 ` KOSAKI Motohiro
2011-06-27 16:40 ` Shawn Bohrer
2011-06-27 18:15 ` Peter Zijlstra
2011-06-27 20:41 ` Darren Hart
2011-06-27 21:08 ` Shawn Bohrer
2011-06-27 21:39 ` Darren Hart
2011-06-27 22:14 ` Shawn Bohrer
2011-06-27 23:17 ` Darren Hart
2011-06-27 22:22 ` [PATCH v3] " Shawn Bohrer
2011-06-28 10:54 ` Peter Zijlstra
2011-06-28 14:52 ` Darren Hart
2011-06-28 17:38 ` Shawn Bohrer
2011-06-28 20:58 ` Darren Hart
2011-06-28 23:55 ` Darren Hart
2011-06-29 14:56 ` Shawn Bohrer
2011-06-29 15:17 ` [PATCH v4] " Shawn Bohrer
2011-06-29 18:41 ` Darren Hart
2011-06-29 23:38 ` Thomas Gleixner
2011-06-30 4:19 ` Darren Hart
2011-06-30 14:02 ` David C. Oliver
2011-06-30 15:41 ` Darren Hart
2011-06-30 16:21 ` [PATCH v5] " Shawn Bohrer
2011-07-12 15:27 ` Shawn Bohrer
2011-07-25 15:20 ` Shawn Bohrer
2011-07-25 19:28 ` Thomas Gleixner
2011-07-26 19:04 ` [tip:core/urgent] " tip-bot for Shawn Bohrer
2011-06-28 10:50 ` [PATCH v2] " Peter Zijlstra
2011-06-28 14:19 ` Darren Hart
2011-06-28 14:23 ` Peter Zijlstra
2011-06-23 3:58 ` [PATCH RFC] " Shawn Bohrer
2011-06-23 3:23 ` Change in functionality of futex() system call KOSAKI Motohiro
-- strict thread matches above, loose matches on Subject: below --
2011-06-09 0:44 George Spelvin
2011-06-09 3:02 ` Darren Hart
2011-06-09 3:38 ` Andrew Lutomirski
2011-06-09 3:54 ` Eric Dumazet
2011-06-09 4:10 ` Andrew Lutomirski
2011-06-09 5:11 ` Eric Dumazet
2011-06-09 12:12 ` Andrew Lutomirski
2011-06-09 4:43 ` George Spelvin
2011-06-09 5:25 ` Eric Dumazet
2011-06-09 4:44 ` Kyle Moffett
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