1 /**************************************************************************
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
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:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
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.
26 **************************************************************************/
28 #include <drm/ttm/ttm_execbuf_util.h>
29 #include <drm/ttm/ttm_bo_driver.h>
30 #include <drm/ttm/ttm_placement.h>
31 #include <linux/wait.h>
32 #include <linux/sched.h>
33 #include <linux/module.h>
35 static void ttm_eu_backoff_reservation_locked(struct list_head
*list
)
37 struct ttm_validate_buffer
*entry
;
39 list_for_each_entry(entry
, list
, head
) {
40 struct ttm_buffer_object
*bo
= entry
->bo
;
44 entry
->reserved
= false;
46 ttm_bo_add_to_lru(bo
);
47 entry
->removed
= false;
49 ww_mutex_unlock(&bo
->resv
->lock
);
53 static void ttm_eu_del_from_lru_locked(struct list_head
*list
)
55 struct ttm_validate_buffer
*entry
;
57 list_for_each_entry(entry
, list
, head
) {
58 struct ttm_buffer_object
*bo
= entry
->bo
;
62 if (!entry
->removed
) {
63 entry
->put_count
= ttm_bo_del_from_lru(bo
);
64 entry
->removed
= true;
69 static void ttm_eu_list_ref_sub(struct list_head
*list
)
71 struct ttm_validate_buffer
*entry
;
73 list_for_each_entry(entry
, list
, head
) {
74 struct ttm_buffer_object
*bo
= entry
->bo
;
76 if (entry
->put_count
) {
77 ttm_bo_list_ref_sub(bo
, entry
->put_count
, true);
83 void ttm_eu_backoff_reservation(struct ww_acquire_ctx
*ticket
,
84 struct list_head
*list
)
86 struct ttm_validate_buffer
*entry
;
87 struct ttm_bo_global
*glob
;
92 entry
= list_first_entry(list
, struct ttm_validate_buffer
, head
);
93 glob
= entry
->bo
->glob
;
94 spin_lock(&glob
->lru_lock
);
95 ttm_eu_backoff_reservation_locked(list
);
97 ww_acquire_fini(ticket
);
98 spin_unlock(&glob
->lru_lock
);
100 EXPORT_SYMBOL(ttm_eu_backoff_reservation
);
103 * Reserve buffers for validation.
105 * If a buffer in the list is marked for CPU access, we back off and
106 * wait for that buffer to become free for GPU access.
108 * If a buffer is reserved for another validation, the validator with
109 * the highest validation sequence backs off and waits for that buffer
110 * to become unreserved. This prevents deadlocks when validating multiple
111 * buffers in different orders.
114 int ttm_eu_reserve_buffers(struct ww_acquire_ctx
*ticket
,
115 struct list_head
*list
)
117 struct ttm_bo_global
*glob
;
118 struct ttm_validate_buffer
*entry
;
121 if (list_empty(list
))
124 list_for_each_entry(entry
, list
, head
) {
125 entry
->reserved
= false;
126 entry
->put_count
= 0;
127 entry
->removed
= false;
130 entry
= list_first_entry(list
, struct ttm_validate_buffer
, head
);
131 glob
= entry
->bo
->glob
;
134 ww_acquire_init(ticket
, &reservation_ww_class
);
136 list_for_each_entry(entry
, list
, head
) {
137 struct ttm_buffer_object
*bo
= entry
->bo
;
139 /* already slowpath reserved? */
143 ret
= ttm_bo_reserve_nolru(bo
, true, (ticket
== NULL
), true,
146 if (ret
== -EDEADLK
) {
147 /* uh oh, we lost out, drop every reservation and try
148 * to only reserve this buffer, then start over if
151 BUG_ON(ticket
== NULL
);
152 spin_lock(&glob
->lru_lock
);
153 ttm_eu_backoff_reservation_locked(list
);
154 spin_unlock(&glob
->lru_lock
);
155 ttm_eu_list_ref_sub(list
);
156 ret
= ww_mutex_lock_slow_interruptible(&bo
->resv
->lock
,
158 if (unlikely(ret
!= 0)) {
164 entry
->reserved
= true;
165 if (unlikely(atomic_read(&bo
->cpu_writers
) > 0)) {
173 entry
->reserved
= true;
174 if (unlikely(atomic_read(&bo
->cpu_writers
) > 0)) {
181 ww_acquire_done(ticket
);
182 spin_lock(&glob
->lru_lock
);
183 ttm_eu_del_from_lru_locked(list
);
184 spin_unlock(&glob
->lru_lock
);
185 ttm_eu_list_ref_sub(list
);
189 spin_lock(&glob
->lru_lock
);
190 ttm_eu_backoff_reservation_locked(list
);
191 spin_unlock(&glob
->lru_lock
);
192 ttm_eu_list_ref_sub(list
);
195 ww_acquire_done(ticket
);
196 ww_acquire_fini(ticket
);
200 EXPORT_SYMBOL(ttm_eu_reserve_buffers
);
202 void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx
*ticket
,
203 struct list_head
*list
, void *sync_obj
)
205 struct ttm_validate_buffer
*entry
;
206 struct ttm_buffer_object
*bo
;
207 struct ttm_bo_global
*glob
;
208 struct ttm_bo_device
*bdev
;
209 struct ttm_bo_driver
*driver
;
211 if (list_empty(list
))
214 bo
= list_first_entry(list
, struct ttm_validate_buffer
, head
)->bo
;
216 driver
= bdev
->driver
;
219 spin_lock(&glob
->lru_lock
);
220 spin_lock(&bdev
->fence_lock
);
222 list_for_each_entry(entry
, list
, head
) {
224 entry
->old_sync_obj
= bo
->sync_obj
;
225 bo
->sync_obj
= driver
->sync_obj_ref(sync_obj
);
226 ttm_bo_add_to_lru(bo
);
227 ww_mutex_unlock(&bo
->resv
->lock
);
228 entry
->reserved
= false;
230 spin_unlock(&bdev
->fence_lock
);
231 spin_unlock(&glob
->lru_lock
);
233 ww_acquire_fini(ticket
);
235 list_for_each_entry(entry
, list
, head
) {
236 if (entry
->old_sync_obj
)
237 driver
->sync_obj_unref(&entry
->old_sync_obj
);
240 EXPORT_SYMBOL(ttm_eu_fence_buffer_objects
);