On Tue, 21 May 2013 20:43:50 +0200 Bart Van Assche <bart.vanass...@gmail.com> wrote:
> Make sure that the round_jiffies*() functions return a time that is > in the future when the jiffies counter is about to wrap. Actually "when the jiffies counter has recently wrapped". I assume this was found by inspection? > @@ -149,9 +149,7 @@ static unsigned long round_jiffies_common(unsigned long > j, int cpu, > /* now that we have rounded, subtract the extra skew again */ > j -= cpu * 3; > - if (j <= jiffies) /* rounding ate our timeout entirely; */ This used to be a very common bug - we've weeded out many instances but I'm sure more still remain. We could perhaps have a checkpatch rule which looks for comparisons against jiffes (and any other time-measuring variables we can detect) and tells people to use time_after() and friends, or time_is_*_jiffies(). > - return original; > - return j; > + return time_is_after_jiffies(j) ? j : original; > } Your email client mangles patches, btw. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
