lkml.org 
[lkml]   [2018]   [Jun]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH V5] powercap/drivers/idle_injection: Add an idle injection framework
On 07-06-18, 10:46, Daniel Lezcano wrote:
> Yes, correct.
>
> But if we don't care about who wins to store to value, is there a risk
> of scramble variable if we just assign a value ?

Normally no, as the compiler wouldn't screw it up badly. But there is no rule
which stops the compiler from doing this:

idle_duration_ms = 5;
idle_duration_ms = -5;
idle_duration_ms = 0;
idle_duration_ms = <real-value-we-want-to-write>;

So we *must* use READ/WRITE_ONCE() to make sure garbage values aren't seen by
readers.

--
viresh

\
 
 \ /
  Last update: 2018-06-07 10:49    [W:0.053 / U:0.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site