lkml.org 
[lkml]   [2011]   [Jun]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: Change in functionality of futex() system call.
From
Date
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.




\
 
 \ /
  Last update: 2011-06-09 14:07    [from the cache]
©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site