On Wed, Jun 24, 2020 at 09:02:47AM +0100, Chris Wilson wrote: > When direct reclaim enters the shrinker and tries to reclaim pages, it > has to opportunitically unmap them [try_to_unmap_one]. For direct > reclaim, the calling context is unknown and may include attempts to > unmap one page of a dma object while attempting to allocate more pages > for that object. Pass the information along that we are inside an > opportunistic unmap that can allow that page to remain referenced and > mapped, and let the callback opt in to avoiding a recursive wait. i915 should already not be holding locks shared with the notifiers across allocations that can trigger reclaim. This is already required to use notifiers correctly anyhow - why do we need something in the notifiers? I really don't like this patch, the purpose of notifiers is only to *track changes* not to influence policy of the callers. Jason
