lkml.org 
[lkml]   [2006]   [Jun]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] ia64: change usermode HZ to 250
From
Date
On Tue, 2006-06-27 at 15:01 -0700, hawkes@sgi.com wrote:
> include/asm-ia64/param.h defines HZ to be 1024 for usermode use, i.e.,
> when the file gets installed as /usr/include/asm/param.h.
> As the comment says:
> Technically, this is wrong, but some old apps still refer to it.
> The proper way to get the HZ value is via sysconf(_SC_CLK_TCK).
> At the very least, this technically wrong #define ought to reflect the
> current default value (250) used by all arch/ia64 platforms. No one uses
> 1024 anymore. This makes those "old apps" (e.g., usr/bin/iostat) behave
> properly for with a default kernel. (And at some point, the define ought
> to be removed altogether, which would expose all the applications that
> erroneously expect HZ to be a compile-time constant.)
>
> Signed-off-by: John Hawkes <hawkes@sgi.com>
>
> Index: linux/include/asm-ia64/param.h
> ===================================================================
> --- linux.orig/include/asm-ia64/param.h 2006-06-17 18:49:35.000000000 -0700
> +++ linux/include/asm-ia64/param.h 2006-06-27 14:46:53.119407077 -0700
> @@ -36,7 +36,7 @@
> * Technically, this is wrong, but some old apps still refer to it. The proper way to
> * get the HZ value is via sysconf(_SC_CLK_TCK).
> */
> -# define HZ 1024
> +# define HZ 250
> #endif

ok why not define the userspace HZ to

#define HZ sysconf(_SC_CLK_TCK)

?


-
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: 2006-06-28 10:42    [from the cache]
©2003-2011 Jasper Spaans