/* $OpenBSD: ttm_execbuf_util.c,v 1.3 2015/04/06 05:35:29 jsg Exp $ */ /************************************************************************** * * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE * USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ #include #include #include static void ttm_eu_backoff_reservation_locked(struct list_head *list) { struct ttm_validate_buffer *entry; list_for_each_entry(entry, list, head) { struct ttm_buffer_object *bo = entry->bo; if (!entry->reserved) continue; if (entry->removed) { ttm_bo_add_to_lru(bo); entry->removed = false; } entry->reserved = false; atomic_set(&bo->reserved, 0); wake_up_all(&bo->event_queue); } } static void ttm_eu_del_from_lru_locked(struct list_head *list) { struct ttm_validate_buffer *entry; list_for_each_entry(entry, list, head) { struct ttm_buffer_object *bo = entry->bo; if (!entry->reserved) continue; if (!entry->removed) { entry->put_count = ttm_bo_del_from_lru(bo); entry->removed = true; } } } static void ttm_eu_list_ref_sub(struct list_head *list) { struct ttm_validate_buffer *entry; list_for_each_entry(entry, list, head) { struct ttm_buffer_object *bo = entry->bo; if (entry->put_count) { ttm_bo_list_ref_sub(bo, entry->put_count, true); entry->put_count = 0; } } } static int ttm_eu_wait_unreserved_locked(struct list_head *list, struct ttm_buffer_object *bo) { struct ttm_bo_global *glob = bo->glob; int ret; ttm_eu_del_from_lru_locked(list); spin_unlock(&glob->lru_lock); ret = ttm_bo_wait_unreserved(bo, true); spin_lock(&glob->lru_lock); if (unlikely(ret != 0)) ttm_eu_backoff_reservation_locked(list); return ret; } void ttm_eu_backoff_reservation(struct list_head *list) { struct ttm_validate_buffer *entry; struct ttm_bo_global *glob; if (list_empty(list)) return; entry = list_first_entry(list, struct ttm_validate_buffer, head); glob = entry->bo->glob; spin_lock(&glob->lru_lock); ttm_eu_backoff_reservation_locked(list); spin_unlock(&glob->lru_lock); } EXPORT_SYMBOL(ttm_eu_backoff_reservation); /* * Reserve buffers for validation. * * If a buffer in the list is marked for CPU access, we back off and * wait for that buffer to become free for GPU access. * * If a buffer is reserved for another validation, the validator with * the highest validation sequence backs off and waits for that buffer * to become unreserved. This prevents deadlocks when validating multiple * buffers in different orders. */ int ttm_eu_reserve_buffers(struct list_head *list) { struct ttm_bo_global *glob; struct ttm_validate_buffer *entry; int ret; uint32_t val_seq; if (list_empty(list)) return 0; list_for_each_entry(entry, list, head) { entry->reserved = false; entry->put_count = 0; entry->removed = false; } entry = list_first_entry(list, struct ttm_validate_buffer, head); glob = entry->bo->glob; retry: spin_lock(&glob->lru_lock); val_seq = entry->bo->bdev->val_seq++; list_for_each_entry(entry, list, head) { struct ttm_buffer_object *bo = entry->bo; retry_this_bo: ret = ttm_bo_reserve_locked(bo, true, true, true, val_seq); switch (ret) { case 0: break; case -EBUSY: ret = ttm_eu_wait_unreserved_locked(list, bo); if (unlikely(ret != 0)) { spin_unlock(&glob->lru_lock); ttm_eu_list_ref_sub(list); return ret; } goto retry_this_bo; case -EAGAIN: ttm_eu_backoff_reservation_locked(list); spin_unlock(&glob->lru_lock); ttm_eu_list_ref_sub(list); ret = ttm_bo_wait_unreserved(bo, true); if (unlikely(ret != 0)) return ret; goto retry; default: ttm_eu_backoff_reservation_locked(list); spin_unlock(&glob->lru_lock); ttm_eu_list_ref_sub(list); return ret; } entry->reserved = true; if (unlikely(atomic_read(&bo->cpu_writers) > 0)) { ttm_eu_backoff_reservation_locked(list); spin_unlock(&glob->lru_lock); ttm_eu_list_ref_sub(list); return -EBUSY; } } ttm_eu_del_from_lru_locked(list); spin_unlock(&glob->lru_lock); ttm_eu_list_ref_sub(list); return 0; } EXPORT_SYMBOL(ttm_eu_reserve_buffers); void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj) { struct ttm_validate_buffer *entry; struct ttm_buffer_object *bo; struct ttm_bo_global *glob; struct ttm_bo_device *bdev; struct ttm_bo_driver *driver; if (list_empty(list)) return; bo = list_first_entry(list, struct ttm_validate_buffer, head)->bo; bdev = bo->bdev; driver = bdev->driver; glob = bo->glob; spin_lock(&glob->lru_lock); spin_lock(&bdev->fence_lock); list_for_each_entry(entry, list, head) { bo = entry->bo; entry->old_sync_obj = bo->sync_obj; bo->sync_obj = driver->sync_obj_ref(sync_obj); ttm_bo_unreserve_locked(bo); entry->reserved = false; } spin_unlock(&bdev->fence_lock); spin_unlock(&glob->lru_lock); list_for_each_entry(entry, list, head) { if (entry->old_sync_obj) driver->sync_obj_unref(&entry->old_sync_obj); } } EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);