On Dec 26, 2007 7:21 AM, Julia Lawall <[EMAIL PROTECTED]> wrote: > - if (jiffies - ent->last_usage < timeout) > + if (time_before(jiffies, ent->last_usage + timeout))
I don't think this is a safe change? subtraction is always safe (if you think about it as 'distance'), addition isn't always safe unless you know the range. The time_before macro will expand that out to (effectively): if ( (long)(ent->last_usage + timeout) - (long)(jiffies) < 0 ) which seems to introduce an overflow condition in the first term. Dunno, I may be wrong (happens often), but at the very least what you've transformed it into is no longer obviously correct, and so it's not a great change. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
