lkml.org 
[lkml]   [2005]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [patch] IBM HDAPS accelerometer driver, with probing.
From
Em Fri, Aug 26, 2005 at 09:06:22PM -0700, Mitchell Blank Jr escreveu:
> Andi Kleen wrote:
> > - it doesn't seem to help that much on modern CPUs with good
> > branch prediction and big icaches anyways.
>
> Really? I would think that as pipelines get deeper (although that trend
> seems to have stopped, thankfully) and Icache-miss penalties get relatively
> larger we'd see unlikely() becoming MORE of a benefit, not less. Storing
> the used part of a "hot" function in 1 Icacheline instead of 4 seems like
> an obvious win.
>
> Personally I've never found unlikely() to be ugly; if anything I think
> it serves as a nice little human-readable comment about whats going on
> in the control-flow. I guess I'm in the minority on that one, though.

Hey, even if unlikely was:

#define unlikely(x) (x)

I'd find it useful :-)

- Arnaldo
-
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: 2005-08-27 07:36    [W:0.047 / U:1.492 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site