On Mon, Jan 20, 2014 at 12:23:40PM +0000, Steven Whitehouse wrote:>Prior to this patch, GFS2 kept all the quotas for eachInteresting! I thought that Sasha Levin had a hash table in the works,
>super block in a single linked list. This is rather slow
>when there are large numbers of quotas.
>This patch introduces a hlist_bl based hash table, similar
>to the one used for glocks. The initial look up of the quota
>is now lockless in the case where it is already cached,
>although we still have to take the per quota spinlock in
>order to bump the ref count. Either way though, this is a
>big improvement on what was there before.
>The qd_lock and the per super block list is preserved, for
>the time being. However it is intended that since this is no
>longer used for its original role, it should be possible to
>shrink the number of items on that list in due course and
>remove the requirement to take qd_lock in qd_get.
>Signed-off-by: Steven Whitehouse<swhiteho@xxxxxxxxxx>
>Cc: Abhijith Das<adas@xxxxxxxxxx>
>Cc: Paul E. McKenney<paulmck@xxxxxxxxxxxxxxxxxx>
but I don't see it, so CCing him.