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
;
45 ttm_bo_add_to_lru(bo
);
46 entry
->removed
= false;
49 entry
->reserved
= false;
50 atomic_set(&bo
->reserved
, 0);
51 wake_up_all(&bo
->event_queue
);
55 static void ttm_eu_del_from_lru_locked(struct list_head
*list
)
57 struct ttm_validate_buffer
*entry
;
59 list_for_each_entry(entry
, list
, head
) {
60 struct ttm_buffer_object
*bo
= entry
->bo
;
64 if (!entry
->removed
) {
65 entry
->put_count
= ttm_bo_del_from_lru(bo
);
66 entry
->removed
= true;
71 static void ttm_eu_list_ref_sub(struct list_head
*list
)
73 struct ttm_validate_buffer
*entry
;
75 list_for_each_entry(entry
, list
, head
) {
76 struct ttm_buffer_object
*bo
= entry
->bo
;
78 if (entry
->put_count
) {
79 ttm_bo_list_ref_sub(bo
, entry
->put_count
, true);
85 void ttm_eu_backoff_reservation(struct list_head
*list
)
87 struct ttm_validate_buffer
*entry
;
88 struct ttm_bo_global
*glob
;
93 entry
= list_first_entry(list
, struct ttm_validate_buffer
, head
);
94 glob
= entry
->bo
->glob
;
95 spin_lock(&glob
->lru_lock
);
96 ttm_eu_backoff_reservation_locked(list
);
97 spin_unlock(&glob
->lru_lock
);
99 EXPORT_SYMBOL(ttm_eu_backoff_reservation
);
102 * Reserve buffers for validation.
104 * If a buffer in the list is marked for CPU access, we back off and
105 * wait for that buffer to become free for GPU access.
107 * If a buffer is reserved for another validation, the validator with
108 * the highest validation sequence backs off and waits for that buffer
109 * to become unreserved. This prevents deadlocks when validating multiple
110 * buffers in different orders.
113 int ttm_eu_reserve_buffers(struct list_head
*list
)
115 struct ttm_bo_global
*glob
;
116 struct ttm_validate_buffer
*entry
;
120 if (list_empty(list
))
123 list_for_each_entry(entry
, list
, head
) {
124 entry
->reserved
= false;
125 entry
->put_count
= 0;
126 entry
->removed
= false;
129 entry
= list_first_entry(list
, struct ttm_validate_buffer
, head
);
130 glob
= entry
->bo
->glob
;
132 spin_lock(&glob
->lru_lock
);
133 val_seq
= entry
->bo
->bdev
->val_seq
++;
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, true, true, val_seq
);
148 ttm_eu_del_from_lru_locked(list
);
149 spin_unlock(&glob
->lru_lock
);
150 ret
= ttm_bo_reserve_nolru(bo
, true, false,
152 spin_lock(&glob
->lru_lock
);
156 if (unlikely(ret
!= -EAGAIN
))
161 ttm_eu_backoff_reservation_locked(list
);
164 * temporarily increase sequence number every retry,
165 * to prevent us from seeing our old reservation
166 * sequence when someone else reserved the buffer,
167 * but hasn't updated the seq_valid/seqno members yet.
169 val_seq
= entry
->bo
->bdev
->val_seq
++;
171 spin_unlock(&glob
->lru_lock
);
172 ttm_eu_list_ref_sub(list
);
173 ret
= ttm_bo_reserve_slowpath_nolru(bo
, true, val_seq
);
174 if (unlikely(ret
!= 0))
176 spin_lock(&glob
->lru_lock
);
177 entry
->reserved
= true;
178 if (unlikely(atomic_read(&bo
->cpu_writers
) > 0)) {
187 entry
->reserved
= true;
188 if (unlikely(atomic_read(&bo
->cpu_writers
) > 0)) {
194 ttm_eu_del_from_lru_locked(list
);
195 spin_unlock(&glob
->lru_lock
);
196 ttm_eu_list_ref_sub(list
);
201 ttm_eu_backoff_reservation_locked(list
);
202 spin_unlock(&glob
->lru_lock
);
203 ttm_eu_list_ref_sub(list
);
206 EXPORT_SYMBOL(ttm_eu_reserve_buffers
);
208 void ttm_eu_fence_buffer_objects(struct list_head
*list
, void *sync_obj
)
210 struct ttm_validate_buffer
*entry
;
211 struct ttm_buffer_object
*bo
;
212 struct ttm_bo_global
*glob
;
213 struct ttm_bo_device
*bdev
;
214 struct ttm_bo_driver
*driver
;
216 if (list_empty(list
))
219 bo
= list_first_entry(list
, struct ttm_validate_buffer
, head
)->bo
;
221 driver
= bdev
->driver
;
224 spin_lock(&glob
->lru_lock
);
225 spin_lock(&bdev
->fence_lock
);
227 list_for_each_entry(entry
, list
, head
) {
229 entry
->old_sync_obj
= bo
->sync_obj
;
230 bo
->sync_obj
= driver
->sync_obj_ref(sync_obj
);
231 ttm_bo_unreserve_locked(bo
);
232 entry
->reserved
= false;
234 spin_unlock(&bdev
->fence_lock
);
235 spin_unlock(&glob
->lru_lock
);
237 list_for_each_entry(entry
, list
, head
) {
238 if (entry
->old_sync_obj
)
239 driver
->sync_obj_unref(&entry
->old_sync_obj
);
242 EXPORT_SYMBOL(ttm_eu_fence_buffer_objects
);