On Thu, 17 Feb 2011 18:05:22 +0100
Peter Zijlstra [off-list ref] wrote:

Hugh says:
 "The only significant loser, I think, would be page reclaim (when
  concurrent with truncation): could spin for a long time waiting for
  the i_mmap_mutex it expects would soon be dropped? "

Counter points:
 - cpu contention makes the spin stop (need_resched())
 - zap pages should be freeing pages at a higher rate than reclaim
   ever can
 - shouldn't hold up reclaim more than lock_page() would

I think the simplification of the truncate code is definately worth
it.

Signed-off-by: Peter Zijlstra <redacted>

Maybe I have to improve batched-uncharge in memcg, whose work depends
on ZAP_BLOCK_SIZE....but the zap routine seems cleaner.

Reviewed-by: KAMEZAWA Hiroyuki <redacted>

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>