lkml.org 
[lkml]   [2006]   [Apr]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 00/05] robust per_cpu allocation for modules
Steven Rostedt writes:

> The data in .data.percpu_offset holds is referenced by the per_cpu
> variable name which points to the __per_cpu_offset array. For modules,
> it will point to the per_cpu_offset array of the module.
>
> Example:
>
> DEFINE_PER_CPU(int, myint);
>
> would now create a variable called per_cpu_offset__myint in
> the .data.percpu_offset section. This variable will point to the (if
> defined in the kernel) __per_cpu_offset[] array. If this was a module
> variable, it would point to the module per_cpu_offset[] array which is
> created when the modules is loaded.

This sounds like you have an extra memory reference each time a
per-cpu variable is accessed. Have you tried to measure the
performance impact of that? If so, how much performance does it lose?

Paul.
-
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: 2006-04-16 08:39    [W:0.101 / U:0.876 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site