linux/drivers/gpu/drm/ttm/ttm_execbuf_util.c
Dave Airlie 1717c0e23f Revert "drm/ttm: add a way to bo_wait for either the last read or last write"
This reverts commit dfadbbdb57.

Further upstream discussion between Marek and Thomas decided this wasn't
fully baked and needed further work, so revert it before it hits mainline.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-27 18:28:37 +02:00

239 lines
6.2 KiB
C

/**************************************************************************
*
* 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>
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);
ret = ttm_bo_wait_cpu(bo, false);
if (ret)
return ret;
goto retry;
}
}
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(&bdev->fence_lock);
spin_lock(&glob->lru_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);
bo->sync_obj_arg = entry->new_sync_obj_arg;
ttm_bo_unreserve_locked(bo);
entry->reserved = false;
}
spin_unlock(&glob->lru_lock);
spin_unlock(&bdev->fence_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);