swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: a9c9a6f741cdaa2fa9ba24a790db8d07295761e3 authored by Linus Torvalds on 02 September 2021, 22:09:46 UTC
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Tip revision: a9c9a6f
ttm_execbuf_util.c
/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/**************************************************************************
*
* 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 <drm/ttm/ttm_execbuf_util.h>
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_placement.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/module.h>
static void ttm_eu_backoff_reservation_reverse(struct list_head *list,
struct ttm_validate_buffer *entry)
{
list_for_each_entry_continue_reverse(entry, list, head) {
struct ttm_buffer_object *bo = entry->bo;
dma_resv_unlock(bo->base.resv);
}
}
void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
struct list_head *list)
{
struct ttm_validate_buffer *entry;
if (list_empty(list))
return;
list_for_each_entry(entry, list, head) {
struct ttm_buffer_object *bo = entry->bo;
ttm_bo_move_to_lru_tail_unlocked(bo);
dma_resv_unlock(bo->base.resv);
}
if (ticket)
ww_acquire_fini(ticket);
}
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 ww_acquire_ctx *ticket,
struct list_head *list, bool intr,
struct list_head *dups)
{
struct ttm_validate_buffer *entry;
int ret;
if (list_empty(list))
return 0;
if (ticket)
ww_acquire_init(ticket, &reservation_ww_class);
list_for_each_entry(entry, list, head) {
struct ttm_buffer_object *bo = entry->bo;
ret = ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
if (ret == -EALREADY && dups) {
struct ttm_validate_buffer *safe = entry;
entry = list_prev_entry(entry, head);
list_del(&safe->head);
list_add(&safe->head, dups);
continue;
}
if (!ret) {
if (!entry->num_shared)
continue;
ret = dma_resv_reserve_shared(bo->base.resv,
entry->num_shared);
if (!ret)
continue;
}
/* uh oh, we lost out, drop every reservation and try
* to only reserve this buffer, then start over if
* this succeeds.
*/
ttm_eu_backoff_reservation_reverse(list, entry);
if (ret == -EDEADLK) {
ret = ttm_bo_reserve_slowpath(bo, intr, ticket);
}
if (!ret && entry->num_shared)
ret = dma_resv_reserve_shared(bo->base.resv,
entry->num_shared);
if (unlikely(ret != 0)) {
if (ticket) {
ww_acquire_done(ticket);
ww_acquire_fini(ticket);
}
return ret;
}
/* move this item to the front of the list,
* forces correct iteration of the loop without keeping track
*/
list_del(&entry->head);
list_add(&entry->head, list);
}
return 0;
}
EXPORT_SYMBOL(ttm_eu_reserve_buffers);
void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
struct list_head *list,
struct dma_fence *fence)
{
struct ttm_validate_buffer *entry;
if (list_empty(list))
return;
list_for_each_entry(entry, list, head) {
struct ttm_buffer_object *bo = entry->bo;
if (entry->num_shared)
dma_resv_add_shared_fence(bo->base.resv, fence);
else
dma_resv_add_excl_fence(bo->base.resv, fence);
ttm_bo_move_to_lru_tail_unlocked(bo);
dma_resv_unlock(bo->base.resv);
}
if (ticket)
ww_acquire_fini(ticket);
}
EXPORT_SYMBOL(ttm_eu_fence_buffer_objects);