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 <dev/pci/drm/ttm/ttm_execbuf_util.h> 29 #include <dev/pci/drm/ttm/ttm_bo_driver.h> 30 #include <dev/pci/drm/ttm/ttm_placement.h> 31 32 static void ttm_eu_backoff_reservation_reverse(struct list_head *list, 33 struct ttm_validate_buffer *entry) 34 { 35 list_for_each_entry_continue_reverse(entry, list, head) { 36 struct ttm_buffer_object *bo = entry->bo; 37 38 __ttm_bo_unreserve(bo); 39 } 40 } 41 42 static void ttm_eu_del_from_lru_locked(struct list_head *list) 43 { 44 struct ttm_validate_buffer *entry; 45 46 list_for_each_entry(entry, list, head) { 47 struct ttm_buffer_object *bo = entry->bo; 48 unsigned put_count = ttm_bo_del_from_lru(bo); 49 50 ttm_bo_list_ref_sub(bo, put_count, true); 51 } 52 } 53 54 void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket, 55 struct list_head *list) 56 { 57 struct ttm_validate_buffer *entry; 58 struct ttm_bo_global *glob; 59 60 if (list_empty(list)) 61 return; 62 63 entry = list_first_entry(list, struct ttm_validate_buffer, head); 64 glob = entry->bo->glob; 65 66 spin_lock(&glob->lru_lock); 67 list_for_each_entry(entry, list, head) { 68 struct ttm_buffer_object *bo = entry->bo; 69 70 ttm_bo_add_to_lru(bo); 71 __ttm_bo_unreserve(bo); 72 } 73 spin_unlock(&glob->lru_lock); 74 75 if (ticket) 76 ww_acquire_fini(ticket); 77 } 78 EXPORT_SYMBOL(ttm_eu_backoff_reservation); 79 80 /* 81 * Reserve buffers for validation. 82 * 83 * If a buffer in the list is marked for CPU access, we back off and 84 * wait for that buffer to become free for GPU access. 85 * 86 * If a buffer is reserved for another validation, the validator with 87 * the highest validation sequence backs off and waits for that buffer 88 * to become unreserved. This prevents deadlocks when validating multiple 89 * buffers in different orders. 90 */ 91 92 int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket, 93 struct list_head *list, bool intr, 94 struct list_head *dups) 95 { 96 struct ttm_bo_global *glob; 97 struct ttm_validate_buffer *entry; 98 int ret; 99 100 if (list_empty(list)) 101 return 0; 102 103 entry = list_first_entry(list, struct ttm_validate_buffer, head); 104 glob = entry->bo->glob; 105 106 if (ticket) 107 ww_acquire_init(ticket, &reservation_ww_class); 108 109 list_for_each_entry(entry, list, head) { 110 struct ttm_buffer_object *bo = entry->bo; 111 112 ret = __ttm_bo_reserve(bo, intr, (ticket == NULL), true, 113 ticket); 114 if (!ret && unlikely(atomic_read(&bo->cpu_writers) > 0)) { 115 __ttm_bo_unreserve(bo); 116 117 ret = -EBUSY; 118 119 } else if (ret == -EALREADY && dups) { 120 struct ttm_validate_buffer *safe = entry; 121 entry = list_prev_entry(entry, head); 122 list_del(&safe->head); 123 list_add(&safe->head, dups); 124 continue; 125 } 126 127 if (!ret) { 128 if (!entry->shared) 129 continue; 130 131 ret = reservation_object_reserve_shared(bo->resv); 132 if (!ret) 133 continue; 134 } 135 136 /* uh oh, we lost out, drop every reservation and try 137 * to only reserve this buffer, then start over if 138 * this succeeds. 139 */ 140 ttm_eu_backoff_reservation_reverse(list, entry); 141 142 if (ret == -EDEADLK && intr) { 143 ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock, 144 ticket); 145 } else if (ret == -EDEADLK) { 146 ww_mutex_lock_slow(&bo->resv->lock, ticket); 147 ret = 0; 148 } 149 150 if (!ret && entry->shared) 151 ret = reservation_object_reserve_shared(bo->resv); 152 153 if (unlikely(ret != 0)) { 154 if (ret == -EINTR) 155 ret = -ERESTARTSYS; 156 if (ticket) { 157 ww_acquire_done(ticket); 158 ww_acquire_fini(ticket); 159 } 160 return ret; 161 } 162 163 /* move this item to the front of the list, 164 * forces correct iteration of the loop without keeping track 165 */ 166 list_del(&entry->head); 167 list_add(&entry->head, list); 168 } 169 170 if (ticket) 171 ww_acquire_done(ticket); 172 spin_lock(&glob->lru_lock); 173 ttm_eu_del_from_lru_locked(list); 174 spin_unlock(&glob->lru_lock); 175 return 0; 176 } 177 EXPORT_SYMBOL(ttm_eu_reserve_buffers); 178 179 void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket, 180 struct list_head *list, struct fence *fence) 181 { 182 struct ttm_validate_buffer *entry; 183 struct ttm_buffer_object *bo; 184 struct ttm_bo_global *glob; 185 struct ttm_bo_device *bdev; 186 struct ttm_bo_driver *driver; 187 188 if (list_empty(list)) 189 return; 190 191 bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo; 192 bdev = bo->bdev; 193 driver = bdev->driver; 194 glob = bo->glob; 195 196 spin_lock(&glob->lru_lock); 197 198 list_for_each_entry(entry, list, head) { 199 bo = entry->bo; 200 if (entry->shared) 201 reservation_object_add_shared_fence(bo->resv, fence); 202 else 203 reservation_object_add_excl_fence(bo->resv, fence); 204 ttm_bo_add_to_lru(bo); 205 __ttm_bo_unreserve(bo); 206 } 207 spin_unlock(&glob->lru_lock); 208 if (ticket) 209 ww_acquire_fini(ticket); 210 } 211 EXPORT_SYMBOL(ttm_eu_fence_buffer_objects); 212