lkml.org 
[lkml]   [2005]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] local_irq_disable removal


I was just trying to get an idea of the possible slow down if any, and for
x86 I'm convinced that it's not a slowdown..

Daniel

On Sun, 12 Jun 2005, Zwane Mwaikambo wrote:

> On Sat, 11 Jun 2005, Daniel Walker wrote:
>
> > Interesting .. So "cli" takes 7 cycles , "sti" takes 7 cycles. The current
> > method does "lea" which takes 1 cycle, and "or" which takes 1 cycle. I'm
> > not sure if there is any function call overhead .. So the soft replacment
> > of cli/sti is 70% faster on a per instruction level .. So it's at least
> > not any slower .. Does everyone agree on that?
>
> Well you also have to take into account the memory access, so it's not
> always that straightforward.
>
> Zwane
>
>

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-06-12 17:50    [W:0.174 / U:0.264 seconds]
©2003-2014 Jasper Spaans. Advertise on this site