Drastically reduce the number of spin lock / unlock operations by performing unreserving and fencing under global locks.
Signed-off-by: Thomas Hellstrom thellstrom@vmware.com --- drivers/gpu/drm/ttm/ttm_bo.c | 11 +++++++-- drivers/gpu/drm/ttm/ttm_execbuf_util.c | 36 ++++++++++++++++++++++--------- include/drm/ttm/ttm_bo_driver.h | 10 ++++++++ include/drm/ttm/ttm_execbuf_util.h | 2 + 4 files changed, 45 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index d93c73b..551a5d3 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -299,14 +299,19 @@ int ttm_bo_reserve(struct ttm_buffer_object *bo, return ret; }
+void ttm_bo_unreserve_locked(struct ttm_buffer_object *bo) +{ + ttm_bo_add_to_lru(bo); + atomic_set(&bo->reserved, 0); + wake_up_all(&bo->event_queue); +} + void ttm_bo_unreserve(struct ttm_buffer_object *bo) { struct ttm_bo_global *glob = bo->glob;
spin_lock(&glob->lru_lock); - ttm_bo_add_to_lru(bo); - atomic_set(&bo->reserved, 0); - wake_up_all(&bo->event_queue); + ttm_bo_unreserve_locked(bo); spin_unlock(&glob->lru_lock); } EXPORT_SYMBOL(ttm_bo_unreserve); diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c b/drivers/gpu/drm/ttm/ttm_execbuf_util.c index a3ae712..7646fb5 100644 --- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c @@ -195,22 +195,36 @@ 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;
- list_for_each_entry(entry, list, head) { - struct ttm_buffer_object *bo = entry->bo; - struct ttm_bo_device *bdev = bo->bdev; - struct ttm_bo_driver *driver = bdev->driver; - void *old_sync_obj; + 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); - old_sync_obj = bo->sync_obj; + 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; - spin_unlock(&bdev->fence_lock); - ttm_bo_unreserve(bo); + ttm_bo_unreserve_locked(bo); entry->reserved = false; - if (old_sync_obj) - driver->sync_obj_unref(&old_sync_obj); + } + 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); diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h index ca8131e..cfb9ca4 100644 --- a/include/drm/ttm/ttm_bo_driver.h +++ b/include/drm/ttm/ttm_bo_driver.h @@ -910,6 +910,16 @@ extern int ttm_bo_reserve_locked(struct ttm_buffer_object *bo, extern void ttm_bo_unreserve(struct ttm_buffer_object *bo);
/** + * ttm_bo_unreserve_locked + * + * @bo: A pointer to a struct ttm_buffer_object. + * + * Unreserve a previous reservation of @bo. + * Needs to be called with struct ttm_bo_global::lru_lock held. + */ +extern void ttm_bo_unreserve_locked(struct ttm_buffer_object *bo); + +/** * ttm_bo_wait_unreserved * * @bo: A pointer to a struct ttm_buffer_object. diff --git a/include/drm/ttm/ttm_execbuf_util.h b/include/drm/ttm/ttm_execbuf_util.h index fd09b84..535ab00 100644 --- a/include/drm/ttm/ttm_execbuf_util.h +++ b/include/drm/ttm/ttm_execbuf_util.h @@ -44,6 +44,7 @@ * @reserved: Indicates whether @bo has been reserved for validation. * @removed: Indicates whether @bo has been removed from lru lists. * @put_count: Number of outstanding references on bo::list_kref. + * @old_sync_obj: Pointer to a sync object about to be unreferenced */
struct ttm_validate_buffer { @@ -53,6 +54,7 @@ struct ttm_validate_buffer { bool reserved; bool removed; int put_count; + void *old_sync_obj; };
/**