[deliverable/linux.git] / drivers / gpu / drm / ttm / ttm_execbuf_util.c

/**************************************************************************
 *
 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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 <drm/ttm/ttm_execbuf_util.h>
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_placement.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/module.h>

static void ttm_eu_backoff_reservation_locked(struct list_head *list,
					      struct ww_acquire_ctx *ticket)
{
	struct ttm_validate_buffer *entry;

	list_for_each_entry(entry, list, head) {
		struct ttm_buffer_object *bo = entry->bo;
		if (!entry->reserved)
			continue;

		entry->reserved = false;
		if (entry->removed) {
			ttm_bo_unreserve_ticket_locked(bo, ticket);
			entry->removed = false;

		} else {
			ww_mutex_unlock(&bo->resv->lock);
		}
	}
}

static void ttm_eu_del_from_lru_locked(struct list_head *list)
{
	struct ttm_validate_buffer *entry;

	list_for_each_entry(entry, list, head) {
		struct ttm_buffer_object *bo = entry->bo;
		if (!entry->reserved)
			continue;

		if (!entry->removed) {
			entry->put_count = ttm_bo_del_from_lru(bo);
			entry->removed = true;
		}
	}
}

static void ttm_eu_list_ref_sub(struct list_head *list)
{
	struct ttm_validate_buffer *entry;

	list_for_each_entry(entry, list, head) {
		struct ttm_buffer_object *bo = entry->bo;

		if (entry->put_count) {
			ttm_bo_list_ref_sub(bo, entry->put_count, true);
			entry->put_count = 0;
		}
	}
}

void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
				struct list_head *list)
{
	struct ttm_validate_buffer *entry;
	struct ttm_bo_global *glob;

	if (list_empty(list))
		return;

	entry = list_first_entry(list, struct ttm_validate_buffer, head);
	glob = entry->bo->glob;
	spin_lock(&glob->lru_lock);
	ttm_eu_backoff_reservation_locked(list, ticket);
	ww_acquire_fini(ticket);
	spin_unlock(&glob->lru_lock);
}
EXPORT_SYMBOL(ttm_eu_backoff_reservation);

/*
 * Reserve buffers for validation.
 *
 * If a buffer in the list is marked for CPU access, we back off and
 * wait for that buffer to become free for GPU access.
 *
 * If a buffer is reserved for another validation, the validator with
 * the highest validation sequence backs off and waits for that buffer
 * to become unreserved. This prevents deadlocks when validating multiple
 * buffers in different orders.
 */

int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
			   struct list_head *list)
{
	struct ttm_bo_global *glob;
	struct ttm_validate_buffer *entry;
	int ret;

	if (list_empty(list))
		return 0;

	list_for_each_entry(entry, list, head) {
		entry->reserved = false;
		entry->put_count = 0;
		entry->removed = false;
	}

	entry = list_first_entry(list, struct ttm_validate_buffer, head);
	glob = entry->bo->glob;

	ww_acquire_init(ticket, &reservation_ww_class);
retry:
	list_for_each_entry(entry, list, head) {
		struct ttm_buffer_object *bo = entry->bo;

		/* already slowpath reserved? */
		if (entry->reserved)
			continue;


		ret = ttm_bo_reserve_nolru(bo, true, false, true, ticket);

		if (ret == -EDEADLK) {
			/* uh oh, we lost out, drop every reservation and try
			 * to only reserve this buffer, then start over if
			 * this succeeds.
			 */
			spin_lock(&glob->lru_lock);
			ttm_eu_backoff_reservation_locked(list, ticket);
			spin_unlock(&glob->lru_lock);
			ttm_eu_list_ref_sub(list);
			ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
							       ticket);
			if (unlikely(ret != 0)) {
				if (ret == -EINTR)
					ret = -ERESTARTSYS;
				goto err_fini;
			}

			entry->reserved = true;
			if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
				ret = -EBUSY;
				goto err;
			}
			goto retry;
		} else if (ret)
			goto err;

		entry->reserved = true;
		if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
			ret = -EBUSY;
			goto err;
		}
	}

	ww_acquire_done(ticket);
	spin_lock(&glob->lru_lock);
	ttm_eu_del_from_lru_locked(list);
	spin_unlock(&glob->lru_lock);
	ttm_eu_list_ref_sub(list);
	return 0;

err:
	spin_lock(&glob->lru_lock);
	ttm_eu_backoff_reservation_locked(list, ticket);
	spin_unlock(&glob->lru_lock);
	ttm_eu_list_ref_sub(list);
err_fini:
	ww_acquire_done(ticket);
	ww_acquire_fini(ticket);
	return ret;
}
EXPORT_SYMBOL(ttm_eu_reserve_buffers);

void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
				 struct list_head *list, void *sync_obj)
{
	struct ttm_validate_buffer *entry;
	struct ttm_buffer_object *bo;
	struct ttm_bo_global *glob;
	struct ttm_bo_device *bdev;
	struct ttm_bo_driver *driver;

	if (list_empty(list))
		return;

	bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo;
	bdev = bo->bdev;
	driver = bdev->driver;
	glob = bo->glob;

	spin_lock(&glob->lru_lock);
	spin_lock(&bdev->fence_lock);

	list_for_each_entry(entry, list, head) {
		bo = entry->bo;
		entry->old_sync_obj = bo->sync_obj;
		bo->sync_obj = driver->sync_obj_ref(sync_obj);
		ttm_bo_unreserve_ticket_locked(bo, ticket);
		entry->reserved = false;
	}
	spin_unlock(&bdev->fence_lock);
	spin_unlock(&glob->lru_lock);
	ww_acquire_fini(ticket);

	list_for_each_entry(entry, list, head) {
		if (entry->old_sync_obj)
			driver->sync_obj_unref(&entry->old_sync_obj);
	}
}
EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);
Commit	Line	Data
c078aa2f TH	1	/**************************************************************************
	2	*
	3	* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
	4	* All Rights Reserved.
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a
	7	* copy of this software and associated documentation files (the
	8	* "Software"), to deal in the Software without restriction, including
	9	* without limitation the rights to use, copy, modify, merge, publish,
	10	* distribute, sub license, and/or sell copies of the Software, and to
	11	* permit persons to whom the Software is furnished to do so, subject to
	12	* the following conditions:
	13	*
	14	* The above copyright notice and this permission notice (including the
	15	* next paragraph) shall be included in all copies or substantial portions
	16	* of the Software.
	17	*
	18	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	19	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	20	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	21	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	22	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	23	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	24	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	25	*
	26	**************************************************************************/
	27
760285e7 DH	28	#include <drm/ttm/ttm_execbuf_util.h>
	29	#include <drm/ttm/ttm_bo_driver.h>
	30	#include <drm/ttm/ttm_placement.h>
c078aa2f TH	31	#include <linux/wait.h>
	32	#include <linux/sched.h>
	33	#include <linux/module.h>
	34
ecff665f ML	35	static void ttm_eu_backoff_reservation_locked(struct list_head *list,
ecff665f ML	36	struct ww_acquire_ctx *ticket)
d6ea8886 DA	37	{
	38	struct ttm_validate_buffer *entry;
	39
	40	list_for_each_entry(entry, list, head) {
	41	struct ttm_buffer_object *bo = entry->bo;
	42	if (!entry->reserved)
	43	continue;
	44
ecff665f	45	entry->reserved = false;
d6ea8886	46	if (entry->removed) {
ecff665f	47	ttm_bo_unreserve_ticket_locked(bo, ticket);
d6ea8886 DA	48	entry->removed = false;
d6ea8886 DA	49
ecff665f	50	} else {
5e338405	51	ww_mutex_unlock(&bo->resv->lock);
d6ea8886	52	}
d6ea8886 DA	53	}
	54	}
	55
	56	static void ttm_eu_del_from_lru_locked(struct list_head *list)
	57	{
	58	struct ttm_validate_buffer *entry;
	59
	60	list_for_each_entry(entry, list, head) {
	61	struct ttm_buffer_object *bo = entry->bo;
	62	if (!entry->reserved)
	63	continue;
	64
	65	if (!entry->removed) {
	66	entry->put_count = ttm_bo_del_from_lru(bo);
	67	entry->removed = true;
	68	}
	69	}
	70	}
	71
	72	static void ttm_eu_list_ref_sub(struct list_head *list)
	73	{
	74	struct ttm_validate_buffer *entry;
	75
	76	list_for_each_entry(entry, list, head) {
	77	struct ttm_buffer_object *bo = entry->bo;
	78
	79	if (entry->put_count) {
	80	ttm_bo_list_ref_sub(bo, entry->put_count, true);
	81	entry->put_count = 0;
	82	}
	83	}
	84	}
	85
ecff665f ML	86	void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
ecff665f ML	87	struct list_head *list)
c078aa2f TH	88	{
c078aa2f TH	89	struct ttm_validate_buffer *entry;
68c4fa31	90	struct ttm_bo_global *glob;
c078aa2f	91
68c4fa31 TH	92	if (list_empty(list))
68c4fa31 TH	93	return;
c078aa2f	94
68c4fa31 TH	95	entry = list_first_entry(list, struct ttm_validate_buffer, head);
	96	glob = entry->bo->glob;
	97	spin_lock(&glob->lru_lock);
ecff665f ML	98	ttm_eu_backoff_reservation_locked(list, ticket);
ecff665f ML	99	ww_acquire_fini(ticket);
68c4fa31	100	spin_unlock(&glob->lru_lock);
c078aa2f TH	101	}
	102	EXPORT_SYMBOL(ttm_eu_backoff_reservation);
	103
	104	/*
	105	* Reserve buffers for validation.
	106	*
	107	* If a buffer in the list is marked for CPU access, we back off and
	108	* wait for that buffer to become free for GPU access.
	109	*
	110	* If a buffer is reserved for another validation, the validator with
	111	* the highest validation sequence backs off and waits for that buffer
	112	* to become unreserved. This prevents deadlocks when validating multiple
	113	* buffers in different orders.
	114	*/
	115
ecff665f ML	116	int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
ecff665f ML	117	struct list_head *list)
c078aa2f	118	{
d6ea8886	119	struct ttm_bo_global *glob;
c078aa2f TH	120	struct ttm_validate_buffer *entry;
	121	int ret;
	122
d6ea8886 DA	123	if (list_empty(list))
	124	return 0;
	125
	126	list_for_each_entry(entry, list, head) {
	127	entry->reserved = false;
	128	entry->put_count = 0;
	129	entry->removed = false;
	130	}
	131
	132	entry = list_first_entry(list, struct ttm_validate_buffer, head);
	133	glob = entry->bo->glob;
	134
ecff665f	135	ww_acquire_init(ticket, &reservation_ww_class);
f2d476a1	136	retry:
c078aa2f TH	137	list_for_each_entry(entry, list, head) {
	138	struct ttm_buffer_object *bo = entry->bo;
	139
f2d476a1 ML	140	/* already slowpath reserved? */
	141	if (entry->reserved)
	142	continue;
	143
7a186308	144
5e338405	145	ret = ttm_bo_reserve_nolru(bo, true, false, true, ticket);
7a186308	146
5e338405 ML	147	if (ret == -EDEADLK) {
	148	/* uh oh, we lost out, drop every reservation and try
	149	* to only reserve this buffer, then start over if
	150	* this succeeds.
	151	*/
	152	spin_lock(&glob->lru_lock);
ecff665f	153	ttm_eu_backoff_reservation_locked(list, ticket);
d6ea8886 DA	154	spin_unlock(&glob->lru_lock);
d6ea8886 DA	155	ttm_eu_list_ref_sub(list);
5e338405 ML	156	ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
	157	ticket);
	158	if (unlikely(ret != 0)) {
	159	if (ret == -EINTR)
	160	ret = -ERESTARTSYS;
ecff665f	161	goto err_fini;
5e338405	162	}
ecff665f	163
f2d476a1 ML	164	entry->reserved = true;
	165	if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
	166	ret = -EBUSY;
	167	goto err;
	168	}
d6ea8886	169	goto retry;
5e338405	170	} else if (ret)
7a186308	171	goto err;
c078aa2f TH	172
	173	entry->reserved = true;
	174	if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
7a186308 ML	175	ret = -EBUSY;
7a186308 ML	176	goto err;
c078aa2f TH	177	}
c078aa2f TH	178	}
d6ea8886	179
ecff665f	180	ww_acquire_done(ticket);
5e338405	181	spin_lock(&glob->lru_lock);
d6ea8886 DA	182	ttm_eu_del_from_lru_locked(list);
	183	spin_unlock(&glob->lru_lock);
	184	ttm_eu_list_ref_sub(list);
c078aa2f	185	return 0;
7a186308 ML	186
7a186308 ML	187	err:
5e338405	188	spin_lock(&glob->lru_lock);
ecff665f	189	ttm_eu_backoff_reservation_locked(list, ticket);
7a186308 ML	190	spin_unlock(&glob->lru_lock);
7a186308 ML	191	ttm_eu_list_ref_sub(list);
ecff665f ML	192	err_fini:
	193	ww_acquire_done(ticket);
	194	ww_acquire_fini(ticket);
7a186308	195	return ret;
c078aa2f TH	196	}
	197	EXPORT_SYMBOL(ttm_eu_reserve_buffers);
	198
ecff665f ML	199	void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
ecff665f ML	200	struct list_head list, void sync_obj)
c078aa2f TH	201	{
c078aa2f TH	202	struct ttm_validate_buffer *entry;
95762c2b TH	203	struct ttm_buffer_object *bo;
	204	struct ttm_bo_global *glob;
	205	struct ttm_bo_device *bdev;
	206	struct ttm_bo_driver *driver;
c078aa2f	207
95762c2b TH	208	if (list_empty(list))
	209	return;
	210
	211	bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo;
	212	bdev = bo->bdev;
	213	driver = bdev->driver;
	214	glob = bo->glob;
c078aa2f	215
95762c2b	216	spin_lock(&glob->lru_lock);
4154f051	217	spin_lock(&bdev->fence_lock);
95762c2b TH	218
	219	list_for_each_entry(entry, list, head) {
	220	bo = entry->bo;
	221	entry->old_sync_obj = bo->sync_obj;
c078aa2f	222	bo->sync_obj = driver->sync_obj_ref(sync_obj);
ecff665f	223	ttm_bo_unreserve_ticket_locked(bo, ticket);
c078aa2f	224	entry->reserved = false;
95762c2b	225	}
95762c2b	226	spin_unlock(&bdev->fence_lock);
4154f051	227	spin_unlock(&glob->lru_lock);
ecff665f	228	ww_acquire_fini(ticket);
95762c2b TH	229
	230	list_for_each_entry(entry, list, head) {
	231	if (entry->old_sync_obj)
	232	driver->sync_obj_unref(&entry->old_sync_obj);
c078aa2f TH	233	}
	234	}
	235	EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);