[PATCH 1/2] mm: add context argument to shrinker callback

[Christoph Hellwig]

On Fri, Apr 23, 2010 at 02:38:01AM +1000, Nick Piggin wrote:
> I don't understand, it should be implemented like just all the other
> shrinkers AFAIKS. Like the dcache one that has to shrink multiple
> superblocks. There is absolutely no requirement for this API change
> to implement it in XFS.

The dcache shrinker is an example for a complete mess.

> But the shrinker list *is* a global list. The downside of it in the way
> it was done in the XFS patch is that 1) it is much larger than a simple
> list head, and 2) not usable by anything other then the shrinker.

It is an existing global list just made more useful.  Whenever a driver
has muliple instances of pool that need shrinking this comes in useful,
it's not related to filesystems at all.