Line data Source code
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 :
36 : static void ttm_eu_backoff_reservation_reverse(struct list_head *list,
37 : struct ttm_validate_buffer *entry)
38 : {
39 0 : list_for_each_entry_continue_reverse(entry, list, head) {
40 0 : struct ttm_buffer_object *bo = entry->bo;
41 :
42 0 : dma_resv_unlock(bo->base.resv);
43 : }
44 : }
45 :
46 0 : void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
47 : struct list_head *list)
48 : {
49 : struct ttm_validate_buffer *entry;
50 :
51 0 : if (list_empty(list))
52 : return;
53 :
54 0 : list_for_each_entry(entry, list, head) {
55 0 : struct ttm_buffer_object *bo = entry->bo;
56 :
57 0 : ttm_bo_move_to_lru_tail_unlocked(bo);
58 0 : dma_resv_unlock(bo->base.resv);
59 : }
60 :
61 : if (ticket)
62 : ww_acquire_fini(ticket);
63 : }
64 : EXPORT_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 :
78 0 : int 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 0 : if (list_empty(list))
86 : return 0;
87 :
88 0 : if (ticket)
89 : ww_acquire_init(ticket, &reservation_ww_class);
90 :
91 0 : list_for_each_entry(entry, list, head) {
92 0 : struct ttm_buffer_object *bo = entry->bo;
93 : unsigned int num_fences;
94 :
95 0 : ret = ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
96 0 : if (ret == -EALREADY && dups) {
97 0 : struct ttm_validate_buffer *safe = entry;
98 0 : entry = list_prev_entry(entry, head);
99 0 : list_del(&safe->head);
100 0 : list_add(&safe->head, dups);
101 0 : continue;
102 : }
103 :
104 0 : num_fences = max(entry->num_shared, 1u);
105 0 : if (!ret) {
106 0 : ret = dma_resv_reserve_fences(bo->base.resv,
107 : num_fences);
108 0 : if (!ret)
109 0 : 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 0 : ttm_eu_backoff_reservation_reverse(list, entry);
117 :
118 0 : if (ret == -EDEADLK) {
119 0 : ret = ttm_bo_reserve_slowpath(bo, intr, ticket);
120 : }
121 :
122 0 : if (!ret)
123 0 : ret = dma_resv_reserve_fences(bo->base.resv,
124 : num_fences);
125 :
126 0 : 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 0 : list_del(&entry->head);
138 0 : list_add(&entry->head, list);
139 : }
140 :
141 : return 0;
142 : }
143 : EXPORT_SYMBOL(ttm_eu_reserve_buffers);
144 :
145 0 : void 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 0 : if (list_empty(list))
152 : return;
153 :
154 0 : list_for_each_entry(entry, list, head) {
155 0 : struct ttm_buffer_object *bo = entry->bo;
156 :
157 0 : 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 0 : dma_resv_unlock(bo->base.resv);
161 : }
162 : if (ticket)
163 : ww_acquire_fini(ticket);
164 : }
165 : EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);
|
