diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_shrinker.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem_shrinker.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c index 9ac78b3d6899..f7929e769250 100644 --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c @@ -47,6 +47,30 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task) #endif } +/** + * i915_gem_shrink - Shrink buffer object caches + * @dev_priv: i915 device + * @target: amount of memory to make available, in pages + * @flags: control 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. + * + * Returns: + * The number of pages of backing storage actually released. + */ unsigned long i915_gem_shrink(struct drm_i915_private *dev_priv, long target, unsigned flags) @@ -118,6 +142,20 @@ i915_gem_shrink(struct drm_i915_private *dev_priv, return count; } +/** + * i915_gem_shrink - Shrink buffer object caches completely + * @dev_priv: i915 device + * + * This is a simple wraper around i915_gem_shrink() to aggressively shrink all + * caches completely. It also first waits for and retires all outstanding + * requests to also be able to release backing storage for active objects. + * + * This should only be used in code to intentionally quiescent the gpu or as a + * last-ditch effort when memory seems to have run out. + * + * Returns: + * The number of pages of backing storage actually released. + */ unsigned long i915_gem_shrink_all(struct drm_i915_private *dev_priv) { i915_gem_evict_everything(dev_priv->dev); @@ -279,6 +317,12 @@ i915_gem_shrinker_oom(struct notifier_block *nb, unsigned long event, void *ptr) return NOTIFY_DONE; } +/** + * i915_gem_shrinker_init - Initialize i915 shrinker + * @dev_priv: i915 device + * + * This function registers and sets up the i915 shrinker and OOM handler. + */ void i915_gem_shrinker_init(struct drm_i915_private *dev_priv) { dev_priv->mm.shrinker.scan_objects = i915_gem_shrinker_scan; |