[mirror_ubuntu-bionic-kernel.git] / drivers / gpu / drm / i915 / i915_gem_shrinker.c

/*
 * Copyright © 2008-2015 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include <linux/oom.h>
#include <linux/shmem_fs.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/pci.h>
#include <linux/dma-buf.h>
#include <drm/drmP.h>
#include <drm/i915_drm.h>

#include "i915_drv.h"
#include "i915_trace.h"

static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
{
	if (!mutex_is_locked(mutex))
		return false;

#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)
	return mutex->owner == task;
#else
	/* Since UP may be pre-empted, we cannot assume that we own the lock */
	return false;
#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,
		unsigned long target, unsigned flags)
{
	const struct {
		struct list_head *list;
		unsigned int bit;
	} phases[] = {
		{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
		{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
		{ NULL, 0 },
	}, *phase;
	unsigned long count = 0;

	trace_i915_gem_shrink(dev_priv, target, flags);

	/*
	 * As we may completely rewrite the (un)bound list whilst unbinding
	 * (due to retiring requests) we have to strictly process only
	 * one element of the list at the time, and recheck the list
	 * on every iteration.
	 *
	 * In particular, we must hold a reference whilst removing the
	 * object as we may end up waiting for and/or retiring the objects.
	 * This might release the final reference (held by the active list)
	 * and result in the object being freed from under us. This is
	 * similar to the precautions the eviction code must take whilst
	 * removing objects.
	 *
	 * Also note that although these lists do not hold a reference to
	 * the object we can safely grab one here: The final object
	 * unreferencing and the bound_list are both protected by the
	 * dev->struct_mutex and so we won't ever be able to observe an
	 * object on the bound_list with a reference count equals 0.
	 */
	for (phase = phases; phase->list; phase++) {
		struct list_head still_in_list;

		if ((flags & phase->bit) == 0)
			continue;

		INIT_LIST_HEAD(&still_in_list);
		while (count < target && !list_empty(phase->list)) {
			struct drm_i915_gem_object *obj;
			struct i915_vma *vma, *v;

			obj = list_first_entry(phase->list,
					       typeof(*obj), global_list);
			list_move_tail(&obj->global_list, &still_in_list);

			if (flags & I915_SHRINK_PURGEABLE &&
			    obj->madv != I915_MADV_DONTNEED)
				continue;

			drm_gem_object_reference(&obj->base);

			/* For the unbound phase, this should be a no-op! */
			list_for_each_entry_safe(vma, v,
						 &obj->vma_list, vma_link)
				if (i915_vma_unbind(vma))
					break;

			if (i915_gem_object_put_pages(obj) == 0)
				count += obj->base.size >> PAGE_SHIFT;

			drm_gem_object_unreference(&obj->base);
		}
		list_splice(&still_in_list, phase->list);
	}

	return count;
}

/**
 * i915_gem_shrink_all - 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);
	return i915_gem_shrink(dev_priv, -1UL,
			       I915_SHRINK_BOUND | I915_SHRINK_UNBOUND);
}

static bool i915_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
{
	if (!mutex_trylock(&dev->struct_mutex)) {
		if (!mutex_is_locked_by(&dev->struct_mutex, current))
			return false;

		if (to_i915(dev)->mm.shrinker_no_lock_stealing)
			return false;

		*unlock = false;
	} else
		*unlock = true;

	return true;
}

static int num_vma_bound(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma;
	int count = 0;

	list_for_each_entry(vma, &obj->vma_list, vma_link) {
		if (drm_mm_node_allocated(&vma->node))
			count++;
		if (vma->pin_count)
			count++;
	}

	return count;
}

static unsigned long
i915_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
{
	struct drm_i915_private *dev_priv =
		container_of(shrinker, struct drm_i915_private, mm.shrinker);
	struct drm_device *dev = dev_priv->dev;
	struct drm_i915_gem_object *obj;
	unsigned long count;
	bool unlock;

	if (!i915_gem_shrinker_lock(dev, &unlock))
		return 0;

	count = 0;
	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list)
		if (obj->pages_pin_count == 0)
			count += obj->base.size >> PAGE_SHIFT;

	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (obj->pages_pin_count == num_vma_bound(obj))
			count += obj->base.size >> PAGE_SHIFT;
	}

	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	return count;
}

static unsigned long
i915_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
{
	struct drm_i915_private *dev_priv =
		container_of(shrinker, struct drm_i915_private, mm.shrinker);
	struct drm_device *dev = dev_priv->dev;
	unsigned long freed;
	bool unlock;

	if (!i915_gem_shrinker_lock(dev, &unlock))
		return SHRINK_STOP;

	freed = i915_gem_shrink(dev_priv,
				sc->nr_to_scan,
				I915_SHRINK_BOUND |
				I915_SHRINK_UNBOUND |
				I915_SHRINK_PURGEABLE);
	if (freed < sc->nr_to_scan)
		freed += i915_gem_shrink(dev_priv,
					 sc->nr_to_scan - freed,
					 I915_SHRINK_BOUND |
					 I915_SHRINK_UNBOUND);
	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	return freed;
}

static int
i915_gem_shrinker_oom(struct notifier_block *nb, unsigned long event, void *ptr)
{
	struct drm_i915_private *dev_priv =
		container_of(nb, struct drm_i915_private, mm.oom_notifier);
	struct drm_device *dev = dev_priv->dev;
	struct drm_i915_gem_object *obj;
	unsigned long timeout = msecs_to_jiffies(5000) + 1;
	unsigned long pinned, bound, unbound, freed_pages;
	bool was_interruptible;
	bool unlock;

	while (!i915_gem_shrinker_lock(dev, &unlock) && --timeout) {
		schedule_timeout_killable(1);
		if (fatal_signal_pending(current))
			return NOTIFY_DONE;
	}
	if (timeout == 0) {
		pr_err("Unable to purge GPU memory due lock contention.\n");
		return NOTIFY_DONE;
	}

	was_interruptible = dev_priv->mm.interruptible;
	dev_priv->mm.interruptible = false;

	freed_pages = i915_gem_shrink_all(dev_priv);

	dev_priv->mm.interruptible = was_interruptible;

	/* Because we may be allocating inside our own driver, we cannot
	 * assert that there are no objects with pinned pages that are not
	 * being pointed to by hardware.
	 */
	unbound = bound = pinned = 0;
	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
		if (!obj->base.filp) /* not backed by a freeable object */
			continue;

		if (obj->pages_pin_count)
			pinned += obj->base.size;
		else
			unbound += obj->base.size;
	}
	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (!obj->base.filp)
			continue;

		if (obj->pages_pin_count)
			pinned += obj->base.size;
		else
			bound += obj->base.size;
	}

	if (unlock)
		mutex_unlock(&dev->struct_mutex);

	if (freed_pages || unbound || bound)
		pr_info("Purging GPU memory, %lu bytes freed, %lu bytes still pinned.\n",
			freed_pages << PAGE_SHIFT, pinned);
	if (unbound || bound)
		pr_err("%lu and %lu bytes still available in the "
		       "bound and unbound GPU page lists.\n",
		       bound, unbound);

	*(unsigned long *)ptr += freed_pages;
	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;
	dev_priv->mm.shrinker.count_objects = i915_gem_shrinker_count;
	dev_priv->mm.shrinker.seeks = DEFAULT_SEEKS;
	register_shrinker(&dev_priv->mm.shrinker);

	dev_priv->mm.oom_notifier.notifier_call = i915_gem_shrinker_oom;
	register_oom_notifier(&dev_priv->mm.oom_notifier);
}
Commit	Line	Data
be6a0376 DV	1	/*
	2	* Copyright © 2008-2015 Intel Corporation
	3	*
	4	* Permission is hereby granted, free of charge, to any person obtaining a
	5	* copy of this software and associated documentation files (the "Software"),
	6	* to deal in the Software without restriction, including without limitation
	7	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	8	* and/or sell copies of the Software, and to permit persons to whom the
	9	* Software is furnished to do so, subject to the following conditions:
	10	*
	11	* The above copyright notice and this permission notice (including the next
	12	* paragraph) shall be included in all copies or substantial portions of the
	13	* Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	19	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	20	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	21	* IN THE SOFTWARE.
	22	*
	23	*/
	24
	25	#include <linux/oom.h>
	26	#include <linux/shmem_fs.h>
	27	#include <linux/slab.h>
	28	#include <linux/swap.h>
	29	#include <linux/pci.h>
	30	#include <linux/dma-buf.h>
	31	#include <drm/drmP.h>
	32	#include <drm/i915_drm.h>
	33
	34	#include "i915_drv.h"
	35	#include "i915_trace.h"
	36
	37	static bool mutex_is_locked_by(struct mutex mutex, struct task_struct task)
	38	{
	39	if (!mutex_is_locked(mutex))
	40	return false;
	41
	42	#if defined(CONFIG_SMP) \|\| defined(CONFIG_DEBUG_MUTEXES)
	43	return mutex->owner == task;
	44	#else
	45	/* Since UP may be pre-empted, we cannot assume that we own the lock */
	46	return false;
	47	#endif
	48	}
	49
eb0b44ad DV	50	/**
	51	* i915_gem_shrink - Shrink buffer object caches
	52	* @dev_priv: i915 device
	53	* @target: amount of memory to make available, in pages
	54	* @flags: control flags for selecting cache types
	55	*
	56	* This function is the main interface to the shrinker. It will try to release
	57	* up to @target pages of main memory backing storage from buffer objects.
	58	* Selection of the specific caches can be done with @flags. This is e.g. useful
	59	* when purgeable objects should be removed from caches preferentially.
	60	*
	61	* Note that it's not guaranteed that released amount is actually available as
	62	* free system memory - the pages might still be in-used to due to other reasons
	63	* (like cpu mmaps) or the mm core has reused them before we could grab them.
	64	* Therefore code that needs to explicitly shrink buffer objects caches (e.g. to
	65	* avoid deadlocks in memory reclaim) must fall back to i915_gem_shrink_all().
	66	*
	67	* Also note that any kind of pinning (both per-vma address space pins and
	68	* backing storage pins at the buffer object level) result in the shrinker code
	69	* having to skip the object.
	70	*
	71	* Returns:
	72	* The number of pages of backing storage actually released.
	73	*/
be6a0376 DV	74	unsigned long
be6a0376 DV	75	i915_gem_shrink(struct drm_i915_private *dev_priv,
14387540	76	unsigned long target, unsigned flags)
be6a0376 DV	77	{
	78	const struct {
	79	struct list_head *list;
	80	unsigned int bit;
	81	} phases[] = {
	82	{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
	83	{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
	84	{ NULL, 0 },
	85	}, *phase;
	86	unsigned long count = 0;
	87
3abafa53 CW	88	trace_i915_gem_shrink(dev_priv, target, flags);
3abafa53 CW	89
be6a0376 DV	90	/*
	91	* As we may completely rewrite the (un)bound list whilst unbinding
	92	* (due to retiring requests) we have to strictly process only
	93	* one element of the list at the time, and recheck the list
	94	* on every iteration.
	95	*
	96	* In particular, we must hold a reference whilst removing the
	97	* object as we may end up waiting for and/or retiring the objects.
	98	* This might release the final reference (held by the active list)
	99	* and result in the object being freed from under us. This is
	100	* similar to the precautions the eviction code must take whilst
	101	* removing objects.
	102	*
	103	* Also note that although these lists do not hold a reference to
	104	* the object we can safely grab one here: The final object
	105	* unreferencing and the bound_list are both protected by the
	106	* dev->struct_mutex and so we won't ever be able to observe an
	107	* object on the bound_list with a reference count equals 0.
	108	*/
	109	for (phase = phases; phase->list; phase++) {
	110	struct list_head still_in_list;
	111
	112	if ((flags & phase->bit) == 0)
	113	continue;
	114
	115	INIT_LIST_HEAD(&still_in_list);
	116	while (count < target && !list_empty(phase->list)) {
	117	struct drm_i915_gem_object *obj;
	118	struct i915_vma vma, v;
	119
	120	obj = list_first_entry(phase->list,
	121	typeof(*obj), global_list);
	122	list_move_tail(&obj->global_list, &still_in_list);
	123
	124	if (flags & I915_SHRINK_PURGEABLE &&
	125	obj->madv != I915_MADV_DONTNEED)
	126	continue;
	127
	128	drm_gem_object_reference(&obj->base);
	129
	130	/* For the unbound phase, this should be a no-op! */
	131	list_for_each_entry_safe(vma, v,
	132	&obj->vma_list, vma_link)
	133	if (i915_vma_unbind(vma))
	134	break;
	135
	136	if (i915_gem_object_put_pages(obj) == 0)
	137	count += obj->base.size >> PAGE_SHIFT;
	138
	139	drm_gem_object_unreference(&obj->base);
	140	}
	141	list_splice(&still_in_list, phase->list);
	142	}
	143
	144	return count;
	145	}
	146
eb0b44ad	147	/**
1f2449cd	148	* i915_gem_shrink_all - Shrink buffer object caches completely
eb0b44ad DV	149	* @dev_priv: i915 device
	150	*
	151	* This is a simple wraper around i915_gem_shrink() to aggressively shrink all
	152	* caches completely. It also first waits for and retires all outstanding
	153	* requests to also be able to release backing storage for active objects.
	154	*
	155	* This should only be used in code to intentionally quiescent the gpu or as a
	156	* last-ditch effort when memory seems to have run out.
	157	*
	158	* Returns:
	159	* The number of pages of backing storage actually released.
	160	*/
be6a0376 DV	161	unsigned long i915_gem_shrink_all(struct drm_i915_private *dev_priv)
	162	{
	163	i915_gem_evict_everything(dev_priv->dev);
14387540	164	return i915_gem_shrink(dev_priv, -1UL,
be6a0376 DV	165	I915_SHRINK_BOUND \| I915_SHRINK_UNBOUND);
	166	}
	167
	168	static bool i915_gem_shrinker_lock(struct drm_device dev, bool unlock)
	169	{
	170	if (!mutex_trylock(&dev->struct_mutex)) {
	171	if (!mutex_is_locked_by(&dev->struct_mutex, current))
	172	return false;
	173
	174	if (to_i915(dev)->mm.shrinker_no_lock_stealing)
	175	return false;
	176
	177	*unlock = false;
	178	} else
	179	*unlock = true;
	180
	181	return true;
	182	}
	183
	184	static int num_vma_bound(struct drm_i915_gem_object *obj)
	185	{
	186	struct i915_vma *vma;
	187	int count = 0;
	188
f6234c1d	189	list_for_each_entry(vma, &obj->vma_list, vma_link) {
be6a0376 DV	190	if (drm_mm_node_allocated(&vma->node))
be6a0376 DV	191	count++;
f6234c1d CW	192	if (vma->pin_count)
	193	count++;
	194	}
be6a0376 DV	195
	196	return count;
	197	}
	198
	199	static unsigned long
	200	i915_gem_shrinker_count(struct shrinker shrinker, struct shrink_control sc)
	201	{
	202	struct drm_i915_private *dev_priv =
	203	container_of(shrinker, struct drm_i915_private, mm.shrinker);
	204	struct drm_device *dev = dev_priv->dev;
	205	struct drm_i915_gem_object *obj;
	206	unsigned long count;
	207	bool unlock;
	208
	209	if (!i915_gem_shrinker_lock(dev, &unlock))
	210	return 0;
	211
	212	count = 0;
	213	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list)
	214	if (obj->pages_pin_count == 0)
	215	count += obj->base.size >> PAGE_SHIFT;
	216
	217	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
f6234c1d	218	if (obj->pages_pin_count == num_vma_bound(obj))
be6a0376 DV	219	count += obj->base.size >> PAGE_SHIFT;
	220	}
	221
	222	if (unlock)
	223	mutex_unlock(&dev->struct_mutex);
	224
	225	return count;
	226	}
	227
	228	static unsigned long
	229	i915_gem_shrinker_scan(struct shrinker shrinker, struct shrink_control sc)
	230	{
	231	struct drm_i915_private *dev_priv =
	232	container_of(shrinker, struct drm_i915_private, mm.shrinker);
	233	struct drm_device *dev = dev_priv->dev;
	234	unsigned long freed;
	235	bool unlock;
	236
	237	if (!i915_gem_shrinker_lock(dev, &unlock))
	238	return SHRINK_STOP;
	239
	240	freed = i915_gem_shrink(dev_priv,
	241	sc->nr_to_scan,
	242	I915_SHRINK_BOUND \|
	243	I915_SHRINK_UNBOUND \|
	244	I915_SHRINK_PURGEABLE);
	245	if (freed < sc->nr_to_scan)
	246	freed += i915_gem_shrink(dev_priv,
	247	sc->nr_to_scan - freed,
	248	I915_SHRINK_BOUND \|
	249	I915_SHRINK_UNBOUND);
	250	if (unlock)
	251	mutex_unlock(&dev->struct_mutex);
	252
	253	return freed;
	254	}
	255
	256	static int
	257	i915_gem_shrinker_oom(struct notifier_block nb, unsigned long event, void ptr)
	258	{
	259	struct drm_i915_private *dev_priv =
	260	container_of(nb, struct drm_i915_private, mm.oom_notifier);
	261	struct drm_device *dev = dev_priv->dev;
	262	struct drm_i915_gem_object *obj;
	263	unsigned long timeout = msecs_to_jiffies(5000) + 1;
	264	unsigned long pinned, bound, unbound, freed_pages;
	265	bool was_interruptible;
	266	bool unlock;
	267
	268	while (!i915_gem_shrinker_lock(dev, &unlock) && --timeout) {
	269	schedule_timeout_killable(1);
	270	if (fatal_signal_pending(current))
	271	return NOTIFY_DONE;
	272	}
	273	if (timeout == 0) {
	274	pr_err("Unable to purge GPU memory due lock contention.\n");
	275	return NOTIFY_DONE;
	276	}
	277
	278	was_interruptible = dev_priv->mm.interruptible;
	279	dev_priv->mm.interruptible = false;
	280
	281	freed_pages = i915_gem_shrink_all(dev_priv);
	282
283	dev_priv->mm.interruptible = was_interruptible;
284
285	/* Because we may be allocating inside our own driver, we cannot
286	* assert that there are no objects with pinned pages that are not
287	* being pointed to by hardware.
288	*/
289	unbound = bound = pinned = 0;
290	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
291	if (!obj->base.filp) /* not backed by a freeable object */
292	continue;
293
294	if (obj->pages_pin_count)
295	pinned += obj->base.size;
296	else
297	unbound += obj->base.size;
298	}
299	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
300	if (!obj->base.filp)
301	continue;
302
303	if (obj->pages_pin_count)
304	pinned += obj->base.size;
305	else
306	bound += obj->base.size;
307	}
308
309	if (unlock)
310	mutex_unlock(&dev->struct_mutex);
311
312	if (freed_pages \|\| unbound \|\| bound)
313	pr_info("Purging GPU memory, %lu bytes freed, %lu bytes still pinned.\n",
314	freed_pages << PAGE_SHIFT, pinned);
315	if (unbound \|\| bound)
316	pr_err("%lu and %lu bytes still available in the "
317	"bound and unbound GPU page lists.\n",
318	bound, unbound);
319
320	(unsigned long )ptr += freed_pages;
321	return NOTIFY_DONE;
322	}
323
eb0b44ad DV	324	/**
	325	* i915_gem_shrinker_init - Initialize i915 shrinker
	326	* @dev_priv: i915 device
	327	*
	328	* This function registers and sets up the i915 shrinker and OOM handler.
	329	*/
be6a0376 DV	330	void i915_gem_shrinker_init(struct drm_i915_private *dev_priv)
	331	{
	332	dev_priv->mm.shrinker.scan_objects = i915_gem_shrinker_scan;
	333	dev_priv->mm.shrinker.count_objects = i915_gem_shrinker_count;
	334	dev_priv->mm.shrinker.seeks = DEFAULT_SEEKS;
	335	register_shrinker(&dev_priv->mm.shrinker);
	336
	337	dev_priv->mm.oom_notifier.notifier_call = i915_gem_shrinker_oom;
	338	register_oom_notifier(&dev_priv->mm.oom_notifier);
	339	}