lkml.org 
[lkml]   [2001]   [May]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [timer] max timeout
george anzinger <george@mvista.com> [01/05/25 17:04]:
> More than enough on the fp. Now the other question.
>
> The time value is in jiffies (aka 1/Hz sec.). The max value (in a 32
> bit system) is 0x7ffffff. This value is added to the current value of
> jiffies to get the the absolute timer expire time. While the value is
> unsigned (and thus you could go higher) the compare code (timer_before()
> and timer_after()) depend on the subtraction (of jiffies from expire) to
> be of the correct sign. To insure this you must keep the timeout values
> sign clear (or if you don't like to think of an unsigned as having a
> sign, then the highest order bit must be zero).
>
> George

The output of `find . -type f | xargs grep 'jiffies +'` would suggest
that there are a few latent bugs as jiffies grows to values near the
top of its range. I guess this hasn't turned up as 0x7fffffff / (100 *
3600 * 24) = 248.55.


-
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: 2005-03-22 13:17    [W:0.477 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site