lkml.org 
[lkml]   [1999]   [Mar]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch] __volatile__ needed in get_cycles()?
On Mon, 29 Mar 1999, Tigran Aivazian wrote:

>which would enforce "Von Neumann execution stream", e.g. by doing CPUID

What is a Von Neumann execution stream? ;)

>first, but one needs to measure the combined cpuid+rdtsc overhead and

Why you need CPUID?

If you need to know some features from the CPU you probably want to use
the information we grabbed at boot time in the current_cpu_data struct.

About the volatile thing the reason I thought it's not needed is that we
care that rdtsc is run always at the same offset of code. We care only
about the _delta_ between the two rdtsc. So basically I seen not using
__volatile__ as a feature. Comments?

Andrea Arcangeli


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

\
 
 \ /
  Last update: 2005-03-22 13:51    [W:0.043 / U:0.504 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site