i915_gem_shrink — Shrink buffer object caches
unsigned long i915_gem_shrink ( | struct drm_i915_private * dev_priv, |
| long target, | |
unsigned flags); |
dev_privi915 device
targetamount of memory to make available, in pages
flagscontrol flags for selecting cache types
This function is the main interface to the shrinker. It will try to release
up to target pages of main memory backing storage from buffer objects.
Selection of the specific caches can be done with flags. This is e.g. useful
when purgeable objects should be removed from caches preferentially.
Note that it's not guaranteed that released amount is actually available as
free system memory - the pages might still be in-used to due to other reasons
(like cpu mmaps) or the mm core has reused them before we could grab them.
Therefore code that needs to explicitly shrink buffer objects caches (e.g. to
avoid deadlocks in memory reclaim) must fall back to i915_gem_shrink_all.
Also note that any kind of pinning (both per-vma address space pins and backing storage pins at the buffer object level) result in the shrinker code having to skip the object.