diff options
author | Thomas Hellstrom <thellstrom@vmware.com> | 2009-12-06 21:46:26 +0100 |
---|---|---|
committer | Dave Airlie <airlied@redhat.com> | 2009-12-07 06:22:05 +0100 |
commit | c078aa2fc4d8e022c3b611e07b25ff77afdf9b73 (patch) | |
tree | 60349ecc7344001b3824529be376b4677012583d /drivers/gpu/drm/ttm/ttm_execbuf_util.c | |
parent | drm/ttm: Add ttm lock functionality. (diff) | |
download | linux-c078aa2fc4d8e022c3b611e07b25ff77afdf9b73.tar.xz linux-c078aa2fc4d8e022c3b611e07b25ff77afdf9b73.zip |
drm/ttm: Add TTM execbuf utilities.
Utilities to reserve, unreserve and fence a list of TTM
buffer objects in a deadlock-safe manner.
Used by the vmwgfx driver.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/ttm/ttm_execbuf_util.c')
-rw-r--r-- | drivers/gpu/drm/ttm/ttm_execbuf_util.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c b/drivers/gpu/drm/ttm/ttm_execbuf_util.c new file mode 100644 index 000000000000..c285c2902d15 --- /dev/null +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c @@ -0,0 +1,117 @@ +/************************************************************************** + * + * 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 "ttm/ttm_execbuf_util.h" +#include "ttm/ttm_bo_driver.h" +#include "ttm/ttm_placement.h" +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/module.h> + +void ttm_eu_backoff_reservation(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; + + entry->reserved = false; + ttm_bo_unreserve(bo); + } +} +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, uint32_t val_seq) +{ + struct ttm_validate_buffer *entry; + int ret; + +retry: + list_for_each_entry(entry, list, head) { + struct ttm_buffer_object *bo = entry->bo; + + entry->reserved = false; + ret = ttm_bo_reserve(bo, true, false, true, val_seq); + if (ret != 0) { + ttm_eu_backoff_reservation(list); + if (ret == -EAGAIN) { + ret = ttm_bo_wait_unreserved(bo, true); + if (unlikely(ret != 0)) + return ret; + goto retry; + } else + return ret; + } + + entry->reserved = true; + if (unlikely(atomic_read(&bo->cpu_writers) > 0)) { + ttm_eu_backoff_reservation(list); + ret = ttm_bo_wait_cpu(bo, false); + if (ret) + return ret; + goto retry; + } + } + 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; + + list_for_each_entry(entry, list, head) { + struct ttm_buffer_object *bo = entry->bo; + struct ttm_bo_driver *driver = bo->bdev->driver; + void *old_sync_obj; + + spin_lock(&bo->lock); + old_sync_obj = bo->sync_obj; + bo->sync_obj = driver->sync_obj_ref(sync_obj); + bo->sync_obj_arg = entry->new_sync_obj_arg; + spin_unlock(&bo->lock); + ttm_bo_unreserve(bo); + entry->reserved = false; + if (old_sync_obj) + driver->sync_obj_unref(&old_sync_obj); + } +} +EXPORT_SYMBOL(ttm_eu_fence_buffer_objects); |