Thomas Hellstrom | c078aa2 | 2009-12-06 21:46:26 +0100 | [diff] [blame] | 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 | |
| 35 | void ttm_eu_backoff_reservation(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 | entry->reserved = false; |
| 45 | ttm_bo_unreserve(bo); |
| 46 | } |
| 47 | } |
| 48 | EXPORT_SYMBOL(ttm_eu_backoff_reservation); |
| 49 | |
| 50 | /* |
| 51 | * Reserve buffers for validation. |
| 52 | * |
| 53 | * If a buffer in the list is marked for CPU access, we back off and |
| 54 | * wait for that buffer to become free for GPU access. |
| 55 | * |
| 56 | * If a buffer is reserved for another validation, the validator with |
| 57 | * the highest validation sequence backs off and waits for that buffer |
| 58 | * to become unreserved. This prevents deadlocks when validating multiple |
| 59 | * buffers in different orders. |
| 60 | */ |
| 61 | |
| 62 | int ttm_eu_reserve_buffers(struct list_head *list, uint32_t val_seq) |
| 63 | { |
| 64 | struct ttm_validate_buffer *entry; |
| 65 | int ret; |
| 66 | |
| 67 | retry: |
| 68 | list_for_each_entry(entry, list, head) { |
| 69 | struct ttm_buffer_object *bo = entry->bo; |
| 70 | |
| 71 | entry->reserved = false; |
| 72 | ret = ttm_bo_reserve(bo, true, false, true, val_seq); |
| 73 | if (ret != 0) { |
| 74 | ttm_eu_backoff_reservation(list); |
| 75 | if (ret == -EAGAIN) { |
| 76 | ret = ttm_bo_wait_unreserved(bo, true); |
| 77 | if (unlikely(ret != 0)) |
| 78 | return ret; |
| 79 | goto retry; |
| 80 | } else |
| 81 | return ret; |
| 82 | } |
| 83 | |
| 84 | entry->reserved = true; |
| 85 | if (unlikely(atomic_read(&bo->cpu_writers) > 0)) { |
| 86 | ttm_eu_backoff_reservation(list); |
| 87 | ret = ttm_bo_wait_cpu(bo, false); |
| 88 | if (ret) |
| 89 | return ret; |
| 90 | goto retry; |
| 91 | } |
| 92 | } |
| 93 | return 0; |
| 94 | } |
| 95 | EXPORT_SYMBOL(ttm_eu_reserve_buffers); |
| 96 | |
| 97 | void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj) |
| 98 | { |
| 99 | struct ttm_validate_buffer *entry; |
| 100 | |
| 101 | list_for_each_entry(entry, list, head) { |
| 102 | struct ttm_buffer_object *bo = entry->bo; |
| 103 | struct ttm_bo_driver *driver = bo->bdev->driver; |
| 104 | void *old_sync_obj; |
| 105 | |
| 106 | spin_lock(&bo->lock); |
| 107 | old_sync_obj = bo->sync_obj; |
| 108 | bo->sync_obj = driver->sync_obj_ref(sync_obj); |
| 109 | bo->sync_obj_arg = entry->new_sync_obj_arg; |
| 110 | spin_unlock(&bo->lock); |
| 111 | ttm_bo_unreserve(bo); |
| 112 | entry->reserved = false; |
| 113 | if (old_sync_obj) |
| 114 | driver->sync_obj_unref(&old_sync_obj); |
| 115 | } |
| 116 | } |
| 117 | EXPORT_SYMBOL(ttm_eu_fence_buffer_objects); |