lkml.org 
[lkml]   [2011]   [Sep]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC][PATCH 4/5] printk: Have wake_up_klogd() use __this_cpu_write()
From
Date
On Tue, 2011-09-20 at 09:54 -0500, Christoph Lameter wrote:
> On Mon, 19 Sep 2011, Steven Rostedt wrote:
>
> > Note, just because something is always in a location that preemption is
> > disabled, does not mean it should use the __this_cpu*() variants.
>
> Why not? If preemption is disabled then the process cannot be migrated to
> another processor. And thus doing the address calculations and operations
> on variables step by step is okay.
>
> > Because if things change, it may become a problem later on.
>
> What things may change? Someone calls the function with preemption
> enabled?

Yes, also, for !x86 you get a redundant preempt_disable/enable pair.




\
 
 \ /
  Last update: 2011-09-20 16:59    [W:0.094 / U:0.488 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site