On Mon, Aug 22, 2011 at 02:17:21PM +0300, Konstantin Khlebnikov wrote: > Shrinker function can returns -1, it means it cannot do anything without a risk of deadlock. > For example prune_super() do this if it cannot grab superblock refrence, even if nr_to_scan=0. > Currenly we interpret this like ULONG_MAX size shrinker, evaluate total_scan according this, > and next time this shrinker can get really big pressure. Let's skip such shrinkers instead. > > Also make total_scan signed, otherwise check (total_scan < 0) below never works. I've got a patch set I am going to post out today that makes this irrelevant. The patch set splits the shrinker api into 2 callbacks - a "count objects" callback and an "scan objects" callback, getting rid of this messy "pass nr-to_scan == 0 to count objects" wart altogether. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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@xxxxxxxxx";> email@xxxxxxxxx </a>