[deliverable/linux.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 <linux/vmalloc.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_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)
	return mutex->owner == task;
#else
	/* Since UP may be pre-empted, we cannot assume that we own the lock */
	return false;
#endif
}

static bool any_vma_pinned(struct drm_i915_gem_object *obj)
{
	struct i915_vma *vma;

	list_for_each_entry(vma, &obj->vma_list, obj_link)
		if (i915_vma_is_pinned(vma))
			return true;

	return false;
}

static bool swap_available(void)
{
	return get_nr_swap_pages() > 0;
}

static bool can_release_pages(struct drm_i915_gem_object *obj)
{
	/* Only shmemfs objects are backed by swap */
	if (!obj->base.filp)
		return false;

	/* Only report true if by unbinding the object and putting its pages
	 * we can actually make forward progress towards freeing physical
	 * pages.
	 *
	 * If the pages are pinned for any other reason than being bound
	 * to the GPU, simply unbinding from the GPU is not going to succeed
	 * in releasing our pin count on the pages themselves.
	 */
	if (obj->pages_pin_count > obj->bind_count)
		return false;

	if (any_vma_pinned(obj))
		return false;

	/* We can only return physical pages to the system if we can either
	 * discard the contents (because the user has marked them as being
	 * purgeable) or if we can move their contents out to swap.
	 */
	return swap_available() || obj->madv == I915_MADV_DONTNEED;
}

/**
 * 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);
	i915_gem_retire_requests(dev_priv);

	/*
	 * Unbinding of objects will require HW access; Let us not wake the
	 * device just to recover a little memory. If absolutely necessary,
	 * we will force the wake during oom-notifier.
	 */
	if ((flags & I915_SHRINK_BOUND) &&
	    !intel_runtime_pm_get_if_in_use(dev_priv))
		flags &= ~I915_SHRINK_BOUND;

	/*
	 * 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;
		struct drm_i915_gem_object *obj;

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

		INIT_LIST_HEAD(&still_in_list);
		while (count < target &&
		       (obj = list_first_entry_or_null(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;

			if (flags & I915_SHRINK_VMAPS &&
			    !is_vmalloc_addr(obj->mapping))
				continue;

			if ((flags & I915_SHRINK_ACTIVE) == 0 &&
			    i915_gem_object_is_active(obj))
				continue;

			if (!can_release_pages(obj))
				continue;

			i915_gem_object_get(obj);

			/* For the unbound phase, this should be a no-op! */
			i915_gem_object_unbind(obj);
			if (i915_gem_object_put_pages(obj) == 0)
				count += obj->base.size >> PAGE_SHIFT;

			i915_gem_object_put(obj);
		}
		list_splice(&still_in_list, phase->list);
	}

	if (flags & I915_SHRINK_BOUND)
		intel_runtime_pm_put(dev_priv);

	i915_gem_retire_requests(dev_priv);
	/* expedite the RCU grace period to free some request slabs */
	synchronize_rcu_expedited();

	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)
{
	unsigned long freed;

	freed = i915_gem_shrink(dev_priv, -1UL,
				I915_SHRINK_BOUND |
				I915_SHRINK_UNBOUND |
				I915_SHRINK_ACTIVE);
	rcu_barrier(); /* wait until our RCU delayed slab frees are completed */

	return freed;
}

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;

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

	return true;
}

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->drm;
	struct drm_i915_gem_object *obj;
	unsigned long count;
	bool unlock;

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

	i915_gem_retire_requests(dev_priv);

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

	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (!i915_gem_object_is_active(obj) && can_release_pages(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->drm;
	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;
}

struct shrinker_lock_uninterruptible {
	bool was_interruptible;
	bool unlock;
};

static bool
i915_gem_shrinker_lock_uninterruptible(struct drm_i915_private *dev_priv,
				       struct shrinker_lock_uninterruptible *slu,
				       int timeout_ms)
{
	unsigned long timeout = jiffies + msecs_to_jiffies_timeout(timeout_ms);

	do {
		if (i915_gem_wait_for_idle(dev_priv, false) == 0 &&
		    i915_gem_shrinker_lock(&dev_priv->drm, &slu->unlock))
			break;

		schedule_timeout_killable(1);
		if (fatal_signal_pending(current))
			return false;

		if (time_after(jiffies, timeout)) {
			pr_err("Unable to lock GPU to purge memory.\n");
			return false;
		}
	} while (1);

	slu->was_interruptible = dev_priv->mm.interruptible;
	dev_priv->mm.interruptible = false;
	return true;
}

static void
i915_gem_shrinker_unlock_uninterruptible(struct drm_i915_private *dev_priv,
					 struct shrinker_lock_uninterruptible *slu)
{
	dev_priv->mm.interruptible = slu->was_interruptible;
	if (slu->unlock)
		mutex_unlock(&dev_priv->drm.struct_mutex);
}

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 shrinker_lock_uninterruptible slu;
	struct drm_i915_gem_object *obj;
	unsigned long unevictable, bound, unbound, freed_pages;

	if (!i915_gem_shrinker_lock_uninterruptible(dev_priv, &slu, 5000))
		return NOTIFY_DONE;

	intel_runtime_pm_get(dev_priv);
	freed_pages = i915_gem_shrink_all(dev_priv);
	intel_runtime_pm_put(dev_priv);

	/* 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 = unevictable = 0;
	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
		if (!can_release_pages(obj))
			unevictable += obj->base.size >> PAGE_SHIFT;
		else
			unbound += obj->base.size >> PAGE_SHIFT;
	}
	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
		if (!can_release_pages(obj))
			unevictable += obj->base.size >> PAGE_SHIFT;
		else
			bound += obj->base.size >> PAGE_SHIFT;
	}

	i915_gem_shrinker_unlock_uninterruptible(dev_priv, &slu);

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

	*(unsigned long *)ptr += freed_pages;
	return NOTIFY_DONE;
}

static int
i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
{
	struct drm_i915_private *dev_priv =
		container_of(nb, struct drm_i915_private, mm.vmap_notifier);
	struct shrinker_lock_uninterruptible slu;
	struct i915_vma *vma, *next;
	unsigned long freed_pages = 0;
	int ret;

	if (!i915_gem_shrinker_lock_uninterruptible(dev_priv, &slu, 5000))
		return NOTIFY_DONE;

	/* Force everything onto the inactive lists */
	ret = i915_gem_wait_for_idle(dev_priv, false);
	if (ret)
		goto out;

	intel_runtime_pm_get(dev_priv);
	freed_pages += i915_gem_shrink(dev_priv, -1UL,
				       I915_SHRINK_BOUND |
				       I915_SHRINK_UNBOUND |
				       I915_SHRINK_ACTIVE |
				       I915_SHRINK_VMAPS);
	intel_runtime_pm_put(dev_priv);

	/* We also want to clear any cached iomaps as they wrap vmap */
	list_for_each_entry_safe(vma, next,
				 &dev_priv->ggtt.base.inactive_list, vm_link) {
		unsigned long count = vma->node.size >> PAGE_SHIFT;
		if (vma->iomap && i915_vma_unbind(vma) == 0)
			freed_pages += count;
	}

out:
	i915_gem_shrinker_unlock_uninterruptible(dev_priv, &slu);

	*(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;
	WARN_ON(register_shrinker(&dev_priv->mm.shrinker));

	dev_priv->mm.oom_notifier.notifier_call = i915_gem_shrinker_oom;
	WARN_ON(register_oom_notifier(&dev_priv->mm.oom_notifier));

	dev_priv->mm.vmap_notifier.notifier_call = i915_gem_shrinker_vmap;
	WARN_ON(register_vmap_purge_notifier(&dev_priv->mm.vmap_notifier));
}

/**
 * i915_gem_shrinker_cleanup - Clean up i915 shrinker
 * @dev_priv: i915 device
 *
 * This function unregisters the i915 shrinker and OOM handler.
 */
void i915_gem_shrinker_cleanup(struct drm_i915_private *dev_priv)
{
	WARN_ON(unregister_vmap_purge_notifier(&dev_priv->mm.vmap_notifier));
	WARN_ON(unregister_oom_notifier(&dev_priv->mm.oom_notifier));
	unregister_shrinker(&dev_priv->mm.shrinker);
}
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>
e87666b5	31	#include <linux/vmalloc.h>
be6a0376 DV	32	#include <drm/drmP.h>
	33	#include <drm/i915_drm.h>
	34
	35	#include "i915_drv.h"
	36	#include "i915_trace.h"
	37
	38	static bool mutex_is_locked_by(struct mutex mutex, struct task_struct task)
	39	{
	40	if (!mutex_is_locked(mutex))
	41	return false;
	42
4f074a53	43	#if defined(CONFIG_DEBUG_MUTEXES) \|\| defined(CONFIG_MUTEX_SPIN_ON_OWNER)
be6a0376 DV	44	return mutex->owner == task;
	45	#else
	46	/* Since UP may be pre-empted, we cannot assume that we own the lock */
	47	return false;
	48	#endif
	49	}
	50
15717de2	51	static bool any_vma_pinned(struct drm_i915_gem_object *obj)
c1a415e2 CW	52	{
c1a415e2 CW	53	struct i915_vma *vma;
c1a415e2	54
15717de2	55	list_for_each_entry(vma, &obj->vma_list, obj_link)
3272db53	56	if (i915_vma_is_pinned(vma))
15717de2	57	return true;
c1a415e2	58
15717de2	59	return false;
c1a415e2 CW	60	}
	61
	62	static bool swap_available(void)
	63	{
	64	return get_nr_swap_pages() > 0;
	65	}
	66
	67	static bool can_release_pages(struct drm_i915_gem_object *obj)
	68	{
1bec9b0b CW	69	/* Only shmemfs objects are backed by swap */
	70	if (!obj->base.filp)
	71	return false;
	72
c1a415e2 CW	73	/* Only report true if by unbinding the object and putting its pages
	74	* we can actually make forward progress towards freeing physical
	75	* pages.
	76	*
	77	* If the pages are pinned for any other reason than being bound
	78	* to the GPU, simply unbinding from the GPU is not going to succeed
	79	* in releasing our pin count on the pages themselves.
	80	*/
15717de2 CW	81	if (obj->pages_pin_count > obj->bind_count)
	82	return false;
	83
	84	if (any_vma_pinned(obj))
c1a415e2 CW	85	return false;
	86
	87	/* We can only return physical pages to the system if we can either
	88	* discard the contents (because the user has marked them as being
	89	* purgeable) or if we can move their contents out to swap.
	90	*/
	91	return swap_available() \|\| obj->madv == I915_MADV_DONTNEED;
	92	}
	93
eb0b44ad DV	94	/**
	95	* i915_gem_shrink - Shrink buffer object caches
	96	* @dev_priv: i915 device
	97	* @target: amount of memory to make available, in pages
	98	* @flags: control flags for selecting cache types
	99	*
	100	* This function is the main interface to the shrinker. It will try to release
	101	* up to @target pages of main memory backing storage from buffer objects.
	102	* Selection of the specific caches can be done with @flags. This is e.g. useful
	103	* when purgeable objects should be removed from caches preferentially.
	104	*
	105	* Note that it's not guaranteed that released amount is actually available as
	106	* free system memory - the pages might still be in-used to due to other reasons
	107	* (like cpu mmaps) or the mm core has reused them before we could grab them.
	108	* Therefore code that needs to explicitly shrink buffer objects caches (e.g. to
	109	* avoid deadlocks in memory reclaim) must fall back to i915_gem_shrink_all().
	110	*
	111	* Also note that any kind of pinning (both per-vma address space pins and
	112	* backing storage pins at the buffer object level) result in the shrinker code
	113	* having to skip the object.
	114	*
	115	* Returns:
	116	* The number of pages of backing storage actually released.
	117	*/
be6a0376 DV	118	unsigned long
be6a0376 DV	119	i915_gem_shrink(struct drm_i915_private *dev_priv,
14387540	120	unsigned long target, unsigned flags)
be6a0376 DV	121	{
	122	const struct {
	123	struct list_head *list;
	124	unsigned int bit;
	125	} phases[] = {
	126	{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
	127	{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
	128	{ NULL, 0 },
	129	}, *phase;
	130	unsigned long count = 0;
	131
3abafa53	132	trace_i915_gem_shrink(dev_priv, target, flags);
c033666a	133	i915_gem_retire_requests(dev_priv);
3abafa53	134
178a30c9 PP	135	/*
	136	* Unbinding of objects will require HW access; Let us not wake the
	137	* device just to recover a little memory. If absolutely necessary,
	138	* we will force the wake during oom-notifier.
	139	*/
	140	if ((flags & I915_SHRINK_BOUND) &&
	141	!intel_runtime_pm_get_if_in_use(dev_priv))
	142	flags &= ~I915_SHRINK_BOUND;
	143
be6a0376 DV	144	/*
	145	* As we may completely rewrite the (un)bound list whilst unbinding
	146	* (due to retiring requests) we have to strictly process only
	147	* one element of the list at the time, and recheck the list
	148	* on every iteration.
	149	*
	150	* In particular, we must hold a reference whilst removing the
	151	* object as we may end up waiting for and/or retiring the objects.
	152	* This might release the final reference (held by the active list)
	153	* and result in the object being freed from under us. This is
	154	* similar to the precautions the eviction code must take whilst
	155	* removing objects.
	156	*
	157	* Also note that although these lists do not hold a reference to
	158	* the object we can safely grab one here: The final object
	159	* unreferencing and the bound_list are both protected by the
	160	* dev->struct_mutex and so we won't ever be able to observe an
	161	* object on the bound_list with a reference count equals 0.
	162	*/
	163	for (phase = phases; phase->list; phase++) {
	164	struct list_head still_in_list;
2a1d7752	165	struct drm_i915_gem_object *obj;
be6a0376 DV	166
	167	if ((flags & phase->bit) == 0)
	168	continue;
	169
	170	INIT_LIST_HEAD(&still_in_list);
2a1d7752 CW	171	while (count < target &&
	172	(obj = list_first_entry_or_null(phase->list,
	173	typeof(*obj),
	174	global_list))) {
be6a0376 DV	175	list_move_tail(&obj->global_list, &still_in_list);
	176
	177	if (flags & I915_SHRINK_PURGEABLE &&
	178	obj->madv != I915_MADV_DONTNEED)
	179	continue;
	180
eae2c43b CW	181	if (flags & I915_SHRINK_VMAPS &&
	182	!is_vmalloc_addr(obj->mapping))
	183	continue;
	184
573adb39 CW	185	if ((flags & I915_SHRINK_ACTIVE) == 0 &&
573adb39 CW	186	i915_gem_object_is_active(obj))
5763ff04 CW	187	continue;
5763ff04 CW	188
c1a415e2 CW	189	if (!can_release_pages(obj))
	190	continue;
	191
25dc556a	192	i915_gem_object_get(obj);
be6a0376 DV	193
be6a0376 DV	194	/* For the unbound phase, this should be a no-op! */
aa653a68	195	i915_gem_object_unbind(obj);
be6a0376 DV	196	if (i915_gem_object_put_pages(obj) == 0)
	197	count += obj->base.size >> PAGE_SHIFT;
	198
f8c417cd	199	i915_gem_object_put(obj);
be6a0376 DV	200	}
	201	list_splice(&still_in_list, phase->list);
	202	}
	203
178a30c9 PP	204	if (flags & I915_SHRINK_BOUND)
	205	intel_runtime_pm_put(dev_priv);
	206
c033666a	207	i915_gem_retire_requests(dev_priv);
0eafec6d CW	208	/* expedite the RCU grace period to free some request slabs */
0eafec6d CW	209	synchronize_rcu_expedited();
c9c0f5ea	210
be6a0376 DV	211	return count;
	212	}
	213
eb0b44ad	214	/**
1f2449cd	215	* i915_gem_shrink_all - Shrink buffer object caches completely
eb0b44ad DV	216	* @dev_priv: i915 device
	217	*
	218	* This is a simple wraper around i915_gem_shrink() to aggressively shrink all
	219	* caches completely. It also first waits for and retires all outstanding
	220	* requests to also be able to release backing storage for active objects.
	221	*
	222	* This should only be used in code to intentionally quiescent the gpu or as a
	223	* last-ditch effort when memory seems to have run out.
	224	*
	225	* Returns:
	226	* The number of pages of backing storage actually released.
	227	*/
be6a0376 DV	228	unsigned long i915_gem_shrink_all(struct drm_i915_private *dev_priv)
be6a0376 DV	229	{
0eafec6d CW	230	unsigned long freed;
	231
	232	freed = i915_gem_shrink(dev_priv, -1UL,
	233	I915_SHRINK_BOUND \|
	234	I915_SHRINK_UNBOUND \|
	235	I915_SHRINK_ACTIVE);
	236	rcu_barrier(); /* wait until our RCU delayed slab frees are completed */
	237
	238	return freed;
be6a0376 DV	239	}
	240
	241	static bool i915_gem_shrinker_lock(struct drm_device dev, bool unlock)
	242	{
	243	if (!mutex_trylock(&dev->struct_mutex)) {
	244	if (!mutex_is_locked_by(&dev->struct_mutex, current))
	245	return false;
	246
be6a0376 DV	247	*unlock = false;
	248	} else
	249	*unlock = true;
	250
	251	return true;
	252	}
	253
be6a0376 DV	254	static unsigned long
	255	i915_gem_shrinker_count(struct shrinker shrinker, struct shrink_control sc)
	256	{
	257	struct drm_i915_private *dev_priv =
	258	container_of(shrinker, struct drm_i915_private, mm.shrinker);
91c8a326	259	struct drm_device *dev = &dev_priv->drm;
be6a0376 DV	260	struct drm_i915_gem_object *obj;
	261	unsigned long count;
	262	bool unlock;
	263
	264	if (!i915_gem_shrinker_lock(dev, &unlock))
	265	return 0;
	266
bed50aea CW	267	i915_gem_retire_requests(dev_priv);
bed50aea CW	268
be6a0376 DV	269	count = 0;
be6a0376 DV	270	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list)
6f0ac204	271	if (can_release_pages(obj))
be6a0376 DV	272	count += obj->base.size >> PAGE_SHIFT;
	273
	274	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
573adb39	275	if (!i915_gem_object_is_active(obj) && can_release_pages(obj))
be6a0376 DV	276	count += obj->base.size >> PAGE_SHIFT;
	277	}
	278
	279	if (unlock)
	280	mutex_unlock(&dev->struct_mutex);
	281
	282	return count;
	283	}
	284
	285	static unsigned long
	286	i915_gem_shrinker_scan(struct shrinker shrinker, struct shrink_control sc)
	287	{
	288	struct drm_i915_private *dev_priv =
	289	container_of(shrinker, struct drm_i915_private, mm.shrinker);
91c8a326	290	struct drm_device *dev = &dev_priv->drm;
be6a0376 DV	291	unsigned long freed;
	292	bool unlock;
	293
	294	if (!i915_gem_shrinker_lock(dev, &unlock))
	295	return SHRINK_STOP;
	296
	297	freed = i915_gem_shrink(dev_priv,
	298	sc->nr_to_scan,
	299	I915_SHRINK_BOUND \|
	300	I915_SHRINK_UNBOUND \|
	301	I915_SHRINK_PURGEABLE);
	302	if (freed < sc->nr_to_scan)
	303	freed += i915_gem_shrink(dev_priv,
	304	sc->nr_to_scan - freed,
	305	I915_SHRINK_BOUND \|
	306	I915_SHRINK_UNBOUND);
	307	if (unlock)
	308	mutex_unlock(&dev->struct_mutex);
	309
	310	return freed;
	311	}
	312
168cf367 CW	313	struct shrinker_lock_uninterruptible {
	314	bool was_interruptible;
	315	bool unlock;
	316	};
	317
	318	static bool
	319	i915_gem_shrinker_lock_uninterruptible(struct drm_i915_private *dev_priv,
	320	struct shrinker_lock_uninterruptible *slu,
	321	int timeout_ms)
	322	{
5cba5be6 CW	323	unsigned long timeout = jiffies + msecs_to_jiffies_timeout(timeout_ms);
	324
	325	do {
	326	if (i915_gem_wait_for_idle(dev_priv, false) == 0 &&
	327	i915_gem_shrinker_lock(&dev_priv->drm, &slu->unlock))
	328	break;
168cf367	329
168cf367 CW	330	schedule_timeout_killable(1);
	331	if (fatal_signal_pending(current))
	332	return false;
5cba5be6 CW	333
5cba5be6 CW	334	if (time_after(jiffies, timeout)) {
168cf367 CW	335	pr_err("Unable to lock GPU to purge memory.\n");
	336	return false;
	337	}
5cba5be6	338	} while (1);
168cf367 CW	339
	340	slu->was_interruptible = dev_priv->mm.interruptible;
	341	dev_priv->mm.interruptible = false;
	342	return true;
	343	}
	344
	345	static void
	346	i915_gem_shrinker_unlock_uninterruptible(struct drm_i915_private *dev_priv,
	347	struct shrinker_lock_uninterruptible *slu)
	348	{
	349	dev_priv->mm.interruptible = slu->was_interruptible;
	350	if (slu->unlock)
91c8a326	351	mutex_unlock(&dev_priv->drm.struct_mutex);
168cf367 CW	352	}
168cf367 CW	353
be6a0376 DV	354	static int
	355	i915_gem_shrinker_oom(struct notifier_block nb, unsigned long event, void ptr)
	356	{
	357	struct drm_i915_private *dev_priv =
	358	container_of(nb, struct drm_i915_private, mm.oom_notifier);
168cf367	359	struct shrinker_lock_uninterruptible slu;
be6a0376	360	struct drm_i915_gem_object *obj;
1768d455	361	unsigned long unevictable, bound, unbound, freed_pages;
be6a0376	362
168cf367	363	if (!i915_gem_shrinker_lock_uninterruptible(dev_priv, &slu, 5000))
be6a0376	364	return NOTIFY_DONE;
be6a0376	365
ea9d9768	366	intel_runtime_pm_get(dev_priv);
be6a0376	367	freed_pages = i915_gem_shrink_all(dev_priv);
ea9d9768	368	intel_runtime_pm_put(dev_priv);
be6a0376	369
be6a0376 DV	370	/* Because we may be allocating inside our own driver, we cannot
	371	* assert that there are no objects with pinned pages that are not
	372	* being pointed to by hardware.
	373	*/
1768d455	374	unbound = bound = unevictable = 0;
be6a0376	375	list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) {
1768d455 CW	376	if (!can_release_pages(obj))
1768d455 CW	377	unevictable += obj->base.size >> PAGE_SHIFT;
be6a0376	378	else
1768d455	379	unbound += obj->base.size >> PAGE_SHIFT;
be6a0376 DV	380	}
be6a0376 DV	381	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
1768d455 CW	382	if (!can_release_pages(obj))
1768d455 CW	383	unevictable += obj->base.size >> PAGE_SHIFT;
be6a0376	384	else
1768d455	385	bound += obj->base.size >> PAGE_SHIFT;
be6a0376 DV	386	}
be6a0376 DV	387
168cf367	388	i915_gem_shrinker_unlock_uninterruptible(dev_priv, &slu);
be6a0376 DV	389
be6a0376 DV	390	if (freed_pages \|\| unbound \|\| bound)
1768d455 CW	391	pr_info("Purging GPU memory, %lu pages freed, "
	392	"%lu pages still pinned.\n",
	393	freed_pages, unevictable);
be6a0376	394	if (unbound \|\| bound)
1768d455	395	pr_err("%lu and %lu pages still available in the "
be6a0376 DV	396	"bound and unbound GPU page lists.\n",
	397	bound, unbound);
	398
	399	(unsigned long )ptr += freed_pages;
	400	return NOTIFY_DONE;
	401	}
	402
e87666b5 CW	403	static int
	404	i915_gem_shrinker_vmap(struct notifier_block nb, unsigned long event, void ptr)
	405	{
	406	struct drm_i915_private *dev_priv =
	407	container_of(nb, struct drm_i915_private, mm.vmap_notifier);
168cf367	408	struct shrinker_lock_uninterruptible slu;
8ef8561f CW	409	struct i915_vma vma, next;
	410	unsigned long freed_pages = 0;
	411	int ret;
e87666b5	412
168cf367	413	if (!i915_gem_shrinker_lock_uninterruptible(dev_priv, &slu, 5000))
e87666b5	414	return NOTIFY_DONE;
e87666b5	415
8ef8561f	416	/* Force everything onto the inactive lists */
dcff85c8	417	ret = i915_gem_wait_for_idle(dev_priv, false);
8ef8561f CW	418	if (ret)
	419	goto out;
	420
ea9d9768	421	intel_runtime_pm_get(dev_priv);
8ef8561f CW	422	freed_pages += i915_gem_shrink(dev_priv, -1UL,
	423	I915_SHRINK_BOUND \|
	424	I915_SHRINK_UNBOUND \|
	425	I915_SHRINK_ACTIVE \|
	426	I915_SHRINK_VMAPS);
ea9d9768	427	intel_runtime_pm_put(dev_priv);
8ef8561f CW	428
	429	/* We also want to clear any cached iomaps as they wrap vmap */
	430	list_for_each_entry_safe(vma, next,
	431	&dev_priv->ggtt.base.inactive_list, vm_link) {
	432	unsigned long count = vma->node.size >> PAGE_SHIFT;
	433	if (vma->iomap && i915_vma_unbind(vma) == 0)
	434	freed_pages += count;
	435	}
e87666b5	436
8ef8561f	437	out:
168cf367	438	i915_gem_shrinker_unlock_uninterruptible(dev_priv, &slu);
e87666b5 CW	439
	440	(unsigned long )ptr += freed_pages;
	441	return NOTIFY_DONE;
	442	}
	443
eb0b44ad DV	444	/**
	445	* i915_gem_shrinker_init - Initialize i915 shrinker
	446	* @dev_priv: i915 device
	447	*
	448	* This function registers and sets up the i915 shrinker and OOM handler.
	449	*/
be6a0376 DV	450	void i915_gem_shrinker_init(struct drm_i915_private *dev_priv)
	451	{
	452	dev_priv->mm.shrinker.scan_objects = i915_gem_shrinker_scan;
	453	dev_priv->mm.shrinker.count_objects = i915_gem_shrinker_count;
	454	dev_priv->mm.shrinker.seeks = DEFAULT_SEEKS;
a8a40589	455	WARN_ON(register_shrinker(&dev_priv->mm.shrinker));
be6a0376 DV	456
be6a0376 DV	457	dev_priv->mm.oom_notifier.notifier_call = i915_gem_shrinker_oom;
a8a40589	458	WARN_ON(register_oom_notifier(&dev_priv->mm.oom_notifier));
e87666b5 CW	459
	460	dev_priv->mm.vmap_notifier.notifier_call = i915_gem_shrinker_vmap;
	461	WARN_ON(register_vmap_purge_notifier(&dev_priv->mm.vmap_notifier));
a8a40589 ID	462	}
	463
	464	/**
	465	* i915_gem_shrinker_cleanup - Clean up i915 shrinker
	466	* @dev_priv: i915 device
	467	*
	468	* This function unregisters the i915 shrinker and OOM handler.
	469	*/
	470	void i915_gem_shrinker_cleanup(struct drm_i915_private *dev_priv)
	471	{
e87666b5	472	WARN_ON(unregister_vmap_purge_notifier(&dev_priv->mm.vmap_notifier));
a8a40589 ID	473	WARN_ON(unregister_oom_notifier(&dev_priv->mm.oom_notifier));
a8a40589 ID	474	unregister_shrinker(&dev_priv->mm.shrinker);
be6a0376	475	}