sys/dev/drm2/ttm/ttm_execbuf_util.c

   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  * $FreeBSD: head/sys/dev/drm2/ttm/ttm_execbuf_util.c 247835 2013-03-05 09:49:34Z kib $
  27  **************************************************************************/
  28
  29 #include <dev/drm2/drmP.h>
  30 #include <dev/drm2/ttm/ttm_execbuf_util.h>
  31 #include <dev/drm2/ttm/ttm_bo_driver.h>
  32 #include <dev/drm2/ttm/ttm_placement.h>
  33
  34 static void ttm_eu_backoff_reservation_locked(struct list_head *list)
  35 {
  36         struct ttm_validate_buffer *entry;
  37
  38         list_for_each_entry(entry, list, head) {
  39                 struct ttm_buffer_object *bo = entry->bo;
  40                 if (!entry->reserved)
  41                         continue;
  42
  43                 if (entry->removed) {
  44                         ttm_bo_add_to_lru(bo);
  45                         entry->removed = false;
  46
  47                 }
  48                 entry->reserved = false;
  49                 atomic_set(&bo->reserved, 0);
  50                 wakeup(bo);
  51         }
  52 }
  53
  54 static void ttm_eu_del_from_lru_locked(struct list_head *list)
  55 {
  56         struct ttm_validate_buffer *entry;
  57
  58         list_for_each_entry(entry, list, head) {
  59                 struct ttm_buffer_object *bo = entry->bo;
  60                 if (!entry->reserved)
  61                         continue;
  62
  63                 if (!entry->removed) {
  64                         entry->put_count = ttm_bo_del_from_lru(bo);
  65                         entry->removed = true;
  66                 }
  67         }
  68 }
  69
  70 static void ttm_eu_list_ref_sub(struct list_head *list)
  71 {
  72         struct ttm_validate_buffer *entry;
  73
  74         list_for_each_entry(entry, list, head) {
  75                 struct ttm_buffer_object *bo = entry->bo;
  76
  77                 if (entry->put_count) {
  78                         ttm_bo_list_ref_sub(bo, entry->put_count, true);
  79                         entry->put_count = 0;
  80                 }
  81         }
  82 }
  83
  84 static int ttm_eu_wait_unreserved_locked(struct list_head *list,
  85                                          struct ttm_buffer_object *bo)
  86 {
  87         int ret;
  88
  89         ttm_eu_del_from_lru_locked(list);
  90         ret = ttm_bo_wait_unreserved_locked(bo, true);
  91         if (unlikely(ret != 0))
  92                 ttm_eu_backoff_reservation_locked(list);
  93         return ret;
  94 }
  95
  96
  97 void ttm_eu_backoff_reservation(struct list_head *list)
  98 {
  99         struct ttm_validate_buffer *entry;
 100         struct ttm_bo_global *glob;
 101
 102         if (list_empty(list))
 103                 return;
 104
 105         entry = list_first_entry(list, struct ttm_validate_buffer, head);
 106         glob = entry->bo->glob;
 107         mtx_lock(&glob->lru_lock);
 108         ttm_eu_backoff_reservation_locked(list);
 109         mtx_unlock(&glob->lru_lock);
 110 }
 111
 112 /*
 113  * Reserve buffers for validation.
 114  *
 115  * If a buffer in the list is marked for CPU access, we back off and
 116  * wait for that buffer to become free for GPU access.
 117  *
 118  * If a buffer is reserved for another validation, the validator with
 119  * the highest validation sequence backs off and waits for that buffer
 120  * to become unreserved. This prevents deadlocks when validating multiple
 121  * buffers in different orders.
 122  */
 123
 124 int ttm_eu_reserve_buffers(struct list_head *list)
 125 {
 126         struct ttm_bo_global *glob;
 127         struct ttm_validate_buffer *entry;
 128         int ret;
 129         uint32_t val_seq;
 130
 131         if (list_empty(list))
 132                 return 0;
 133
 134         list_for_each_entry(entry, list, head) {
 135                 entry->reserved = false;
 136                 entry->put_count = 0;
 137                 entry->removed = false;
 138         }
 139
 140         entry = list_first_entry(list, struct ttm_validate_buffer, head);
 141         glob = entry->bo->glob;
 142
 143         mtx_lock(&glob->lru_lock);
 144 retry_locked:
 145         val_seq = entry->bo->bdev->val_seq++;
 146
 147         list_for_each_entry(entry, list, head) {
 148                 struct ttm_buffer_object *bo = entry->bo;
 149
 150 retry_this_bo:
 151                 ret = ttm_bo_reserve_locked(bo, true, true, true, val_seq);
 152                 switch (ret) {
 153                 case 0:
 154                         break;
 155                 case -EBUSY:
 156                         ret = ttm_eu_wait_unreserved_locked(list, bo);
 157                         if (unlikely(ret != 0)) {
 158                                 mtx_unlock(&glob->lru_lock);
 159                                 ttm_eu_list_ref_sub(list);
 160                                 return ret;
 161                         }
 162                         goto retry_this_bo;
 163                 case -EAGAIN:
 164                         ttm_eu_backoff_reservation_locked(list);
 165                         ttm_eu_list_ref_sub(list);
 166                         ret = ttm_bo_wait_unreserved_locked(bo, true);
 167                         if (unlikely(ret != 0)) {
 168                                 mtx_unlock(&glob->lru_lock);
 169                                 return ret;
 170                         }
 171                         goto retry_locked;
 172                 default:
 173                         ttm_eu_backoff_reservation_locked(list);
 174                         mtx_unlock(&glob->lru_lock);
 175                         ttm_eu_list_ref_sub(list);
 176                         return ret;
 177                 }
 178
 179                 entry->reserved = true;
 180                 if (unlikely(atomic_read(&bo->cpu_writers) > 0)) {
 181                         ttm_eu_backoff_reservation_locked(list);
 182                         mtx_unlock(&glob->lru_lock);
 183                         ttm_eu_list_ref_sub(list);
 184                         return -EBUSY;
 185                 }
 186         }
 187
 188         ttm_eu_del_from_lru_locked(list);
 189         mtx_unlock(&glob->lru_lock);
 190         ttm_eu_list_ref_sub(list);
 191
 192         return 0;
 193 }
 194
 195 void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj)
 196 {
 197         struct ttm_validate_buffer *entry;
 198         struct ttm_buffer_object *bo;
 199         struct ttm_bo_global *glob;
 200         struct ttm_bo_device *bdev;
 201         struct ttm_bo_driver *driver;
 202
 203         if (list_empty(list))
 204                 return;
 205
 206         bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo;
 207         bdev = bo->bdev;
 208         driver = bdev->driver;
 209         glob = bo->glob;
 210
 211         mtx_lock(&glob->lru_lock);
 212         mtx_lock(&bdev->fence_lock);
 213
 214         list_for_each_entry(entry, list, head) {
 215                 bo = entry->bo;
 216                 entry->old_sync_obj = bo->sync_obj;
 217                 bo->sync_obj = driver->sync_obj_ref(sync_obj);
 218                 ttm_bo_unreserve_locked(bo);
 219                 entry->reserved = false;
 220         }
 221         mtx_unlock(&bdev->fence_lock);
 222         mtx_unlock(&glob->lru_lock);
 223
 224         list_for_each_entry(entry, list, head) {
 225                 if (entry->old_sync_obj)
 226                         driver->sync_obj_unref(&entry->old_sync_obj);
 227         }
 228 }