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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
28#include "ttm/ttm_execbuf_util.h"
29#include "ttm/ttm_bo_driver.h"
30#include "ttm/ttm_placement.h"
31#include <linux/wait.h>
32#include <linux/sched.h>
33#include <linux/module.h>
34
35static void ttm_eu_backoff_reservation_locked(struct list_head *list)
36{
37 struct ttm_validate_buffer *entry;
38
39 list_for_each_entry(entry, list, head) {
40 struct ttm_buffer_object *bo = entry->bo;
41 if (!entry->reserved)
42 continue;
43
44 if (entry->removed) {
45 ttm_bo_add_to_lru(bo);
46 entry->removed = false;
47
48 }
49 entry->reserved = false;
50 atomic_set(&bo->reserved, 0);
51 wake_up_all(&bo->event_queue);
52 }
53}
54
55static void ttm_eu_del_from_lru_locked(struct list_head *list)
56{
57 struct ttm_validate_buffer *entry;
58
59 list_for_each_entry(entry, list, head) {
60 struct ttm_buffer_object *bo = entry->bo;
61 if (!entry->reserved)
62 continue;
63
64 if (!entry->removed) {
65 entry->put_count = ttm_bo_del_from_lru(bo);
66 entry->removed = true;
67 }
68 }
69}
70
71static void ttm_eu_list_ref_sub(struct list_head *list)
72{
73 struct ttm_validate_buffer *entry;
74
75 list_for_each_entry(entry, list, head) {
76 struct ttm_buffer_object *bo = entry->bo;
77
78 if (entry->put_count) {
79 ttm_bo_list_ref_sub(bo, entry->put_count, true);
80 entry->put_count = 0;
81 }
82 }
83}
84
85static int ttm_eu_wait_unreserved_locked(struct list_head *list,
86 struct ttm_buffer_object *bo)
87{
88 struct ttm_bo_global *glob = bo->glob;
89 int ret;
90
91 ttm_eu_del_from_lru_locked(list);
92 spin_unlock(&glob->lru_lock);
93 ret = ttm_bo_wait_unreserved(bo, true);
94 spin_lock(&glob->lru_lock);
95 if (unlikely(ret != 0))
96 ttm_eu_backoff_reservation_locked(list);
97 return ret;
98}
99
100
101void ttm_eu_backoff_reservation(struct list_head *list)
102{
103 struct ttm_validate_buffer *entry;
104 struct ttm_bo_global *glob;
105
106 if (list_empty(list))
107 return;
108
109 entry = list_first_entry(list, struct ttm_validate_buffer, head);
110 glob = entry->bo->glob;
111 spin_lock(&glob->lru_lock);
112 ttm_eu_backoff_reservation_locked(list);
113 spin_unlock(&glob->lru_lock);
114}
115EXPORT_SYMBOL(ttm_eu_backoff_reservation);
116
117/*
118 * Reserve buffers for validation.
119 *
120 * If a buffer in the list is marked for CPU access, we back off and
121 * wait for that buffer to become free for GPU access.
122 *
123 * If a buffer is reserved for another validation, the validator with
124 * the highest validation sequence backs off and waits for that buffer
125 * to become unreserved. This prevents deadlocks when validating multiple
126 * buffers in different orders.
127 */
128
129int ttm_eu_reserve_buffers(struct list_head *list)
130{
131 struct ttm_bo_global *glob;
132 struct ttm_validate_buffer *entry;
133 int ret;
134 uint32_t val_seq;
135
136 if (list_empty(list))
137 return 0;
138
139 list_for_each_entry(entry, list, head) {
140 entry->reserved = false;
141 entry->put_count = 0;
142 entry->removed = false;
143 }
144
145 entry = list_first_entry(list, struct ttm_validate_buffer, head);
146 glob = entry->bo->glob;
147
148retry:
149 spin_lock(&glob->lru_lock);
150 val_seq = entry->bo->bdev->val_seq++;
151
152 list_for_each_entry(entry, list, head) {
153 struct ttm_buffer_object *bo = entry->bo;
154
155retry_this_bo:
156 ret = ttm_bo_reserve_locked(bo, true, true, true, val_seq);
157 switch (ret) {
158 case 0:
159 break;
160 case -EBUSY:
161 ret = ttm_eu_wait_unreserved_locked(list, bo);
162 if (unlikely(ret != 0)) {
163 spin_unlock(&glob->lru_lock);
164 ttm_eu_list_ref_sub(list);
165 return ret;
166 }
167 goto retry_this_bo;
168 case -EAGAIN:
169 ttm_eu_backoff_reservation_locked(list);
170 spin_unlock(&glob->lru_lock);
171 ttm_eu_list_ref_sub(list);
172 ret = ttm_bo_wait_unreserved(bo, true);
173 if (unlikely(ret != 0))
174 return ret;
175 goto retry;
176 default:
177 ttm_eu_backoff_reservation_locked(list);
178 spin_unlock(&glob->lru_lock);
179 ttm_eu_list_ref_sub(list);
180 return ret;
181 }
182
183 entry->reserved = true;
184 if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
185 ttm_eu_backoff_reservation_locked(list);
186 spin_unlock(&glob->lru_lock);
187 ttm_eu_list_ref_sub(list);
188 ret = ttm_bo_wait_cpu(bo, false);
189 if (ret)
190 return ret;
191 goto retry;
192 }
193 }
194
195 ttm_eu_del_from_lru_locked(list);
196 spin_unlock(&glob->lru_lock);
197 ttm_eu_list_ref_sub(list);
198
199 return 0;
200}
201EXPORT_SYMBOL(ttm_eu_reserve_buffers);
202
203void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj)
204{
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;
210
211 if (list_empty(list))
212 return;
213
214 bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo;
215 bdev = bo->bdev;
216 driver = bdev->driver;
217 glob = bo->glob;
218
219 spin_lock(&bdev->fence_lock);
220 spin_lock(&glob->lru_lock);
221
222 list_for_each_entry(entry, list, head) {
223 bo = entry->bo;
224 entry->old_sync_obj = bo->sync_obj;
225 bo->sync_obj = driver->sync_obj_ref(sync_obj);
226 bo->sync_obj_arg = entry->new_sync_obj_arg;
227 ttm_bo_unreserve_locked(bo);
228 entry->reserved = false;
229 }
230 spin_unlock(&glob->lru_lock);
231 spin_unlock(&bdev->fence_lock);
232
233 list_for_each_entry(entry, list, head) {
234 if (entry->old_sync_obj)
235 driver->sync_obj_unref(&entry->old_sync_obj);
236 }
237}
238EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);
1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
2/**************************************************************************
3 *
4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28
29#include <drm/ttm/ttm_execbuf_util.h>
30#include <drm/ttm/ttm_bo_driver.h>
31#include <drm/ttm/ttm_placement.h>
32#include <linux/wait.h>
33#include <linux/sched.h>
34#include <linux/module.h>
35
36static void ttm_eu_backoff_reservation_reverse(struct list_head *list,
37 struct ttm_validate_buffer *entry)
38{
39 list_for_each_entry_continue_reverse(entry, list, head) {
40 struct ttm_buffer_object *bo = entry->bo;
41
42 dma_resv_unlock(bo->base.resv);
43 }
44}
45
46void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
47 struct list_head *list)
48{
49 struct ttm_validate_buffer *entry;
50
51 if (list_empty(list))
52 return;
53
54 list_for_each_entry(entry, list, head) {
55 struct ttm_buffer_object *bo = entry->bo;
56
57 ttm_bo_move_to_lru_tail_unlocked(bo);
58 dma_resv_unlock(bo->base.resv);
59 }
60
61 if (ticket)
62 ww_acquire_fini(ticket);
63}
64EXPORT_SYMBOL(ttm_eu_backoff_reservation);
65
66/*
67 * Reserve buffers for validation.
68 *
69 * If a buffer in the list is marked for CPU access, we back off and
70 * wait for that buffer to become free for GPU access.
71 *
72 * If a buffer is reserved for another validation, the validator with
73 * the highest validation sequence backs off and waits for that buffer
74 * to become unreserved. This prevents deadlocks when validating multiple
75 * buffers in different orders.
76 */
77
78int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
79 struct list_head *list, bool intr,
80 struct list_head *dups)
81{
82 struct ttm_validate_buffer *entry;
83 int ret;
84
85 if (list_empty(list))
86 return 0;
87
88 if (ticket)
89 ww_acquire_init(ticket, &reservation_ww_class);
90
91 list_for_each_entry(entry, list, head) {
92 struct ttm_buffer_object *bo = entry->bo;
93 unsigned int num_fences;
94
95 ret = ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
96 if (ret == -EALREADY && dups) {
97 struct ttm_validate_buffer *safe = entry;
98 entry = list_prev_entry(entry, head);
99 list_del(&safe->head);
100 list_add(&safe->head, dups);
101 continue;
102 }
103
104 num_fences = max(entry->num_shared, 1u);
105 if (!ret) {
106 ret = dma_resv_reserve_fences(bo->base.resv,
107 num_fences);
108 if (!ret)
109 continue;
110 }
111
112 /* uh oh, we lost out, drop every reservation and try
113 * to only reserve this buffer, then start over if
114 * this succeeds.
115 */
116 ttm_eu_backoff_reservation_reverse(list, entry);
117
118 if (ret == -EDEADLK) {
119 ret = ttm_bo_reserve_slowpath(bo, intr, ticket);
120 }
121
122 if (!ret)
123 ret = dma_resv_reserve_fences(bo->base.resv,
124 num_fences);
125
126 if (unlikely(ret != 0)) {
127 if (ticket) {
128 ww_acquire_done(ticket);
129 ww_acquire_fini(ticket);
130 }
131 return ret;
132 }
133
134 /* move this item to the front of the list,
135 * forces correct iteration of the loop without keeping track
136 */
137 list_del(&entry->head);
138 list_add(&entry->head, list);
139 }
140
141 return 0;
142}
143EXPORT_SYMBOL(ttm_eu_reserve_buffers);
144
145void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
146 struct list_head *list,
147 struct dma_fence *fence)
148{
149 struct ttm_validate_buffer *entry;
150
151 if (list_empty(list))
152 return;
153
154 list_for_each_entry(entry, list, head) {
155 struct ttm_buffer_object *bo = entry->bo;
156
157 dma_resv_add_fence(bo->base.resv, fence, entry->num_shared ?
158 DMA_RESV_USAGE_READ : DMA_RESV_USAGE_WRITE);
159 ttm_bo_move_to_lru_tail_unlocked(bo);
160 dma_resv_unlock(bo->base.resv);
161 }
162 if (ticket)
163 ww_acquire_fini(ticket);
164}
165EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);