[lkml]   [2018]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v2 03/36] mm: use do_futex() instead of sys_futex() in mm_release()
On Thu, Mar 15, 2018 at 08:04:56PM +0100, Dominik Brodowski wrote:
> sys_futex() is a wrapper to do_futex() which does not modify any
> values here:
> - uaddr, val and val3 are kept the same
> - op is masked with FUTEX_CMD_MASK, but is always set to FUTEX_WAKE.
> Therefore, val2 is always 0.
> - as utime is set to NULL, *timeout is NULL
> Cc: Thomas Gleixner <>
> Cc: Ingo Molnar <>
> Cc: Peter Zijlstra <>
> Cc: Darren Hart <>
> Cc: Andrew Morton <>
> Signed-off-by: Dominik Brodowski <>

Hi Dominik,

I'm missing the "why" part here. What is it you are trying to address?

do_futex is not currently in use outside of the futex implementation,
while sys_futex is. This decouples the interface from the
implementation. While this is perhaps less critical within the
kernel, I don't see a compelling reason to increase the coupling
between the mm and futex implementations.

Without a compelling WHY, Nack from me.

Darren Hart
VMware Open Source Technology Center

 \ /
  Last update: 2018-03-16 19:44    [W:0.252 / U:1.604 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site