Re: [PATCH] low-latency zap_page_range

Robert Love
2002-07-22T17:16:40Z

On Sun, 2002-07-21 at 22:20, Andrew Morton wrote:

> There are actually quite a few places in the ll patch which don't
> pass ZPR_COND_RESCHED into zap_page_range. Places which are
> themselves called under locks, places where not enough pages
> are being zapped to make it necessary, etc. vmtruncate_list,
> some mremap code, others.

The bonus of the approach in my patch is that we won't reschedule unless
the lock count is zero (due to the preemptive kernel), so we do not need
to worry about the above. The only concern would be if there is ever a
case where the critical region is the entire chunk we want to zap (e.g.
we must zap the entire inputted range atomically) but I do not see that
ever being the case.

Robert Love