With the lru lock no longer required for protecting reservations we can just do a ttm_bo_reserve_nolru on -EBUSY, and handle all errors in a single path.
Signed-off-by: Maarten Lankhorst maarten.lankhorst@canonical.com Reviewed-by: Jerome Glisse jglisse@redhat.com --- drivers/gpu/drm/ttm/ttm_execbuf_util.c | 53 ++++++++++++++-------------------- 1 file changed, 21 insertions(+), 32 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c b/drivers/gpu/drm/ttm/ttm_execbuf_util.c index bd37b5c..c7d3236 100644 --- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c @@ -82,22 +82,6 @@ static void ttm_eu_list_ref_sub(struct list_head *list) } }
-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; @@ -152,19 +136,23 @@ retry: list_for_each_entry(entry, list, head) { struct ttm_buffer_object *bo = entry->bo;
-retry_this_bo: ret = ttm_bo_reserve_nolru(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; + ttm_eu_del_from_lru_locked(list); + spin_unlock(&glob->lru_lock); + ret = ttm_bo_reserve_nolru(bo, true, false, + true, val_seq); + spin_lock(&glob->lru_lock); + if (!ret) + break; + + if (unlikely(ret != -EAGAIN)) + goto err; + + /* fallthrough */ case -EAGAIN: ttm_eu_backoff_reservation_locked(list); spin_unlock(&glob->lru_lock); @@ -174,18 +162,13 @@ retry_this_bo: return ret; goto retry; default: - ttm_eu_backoff_reservation_locked(list); - spin_unlock(&glob->lru_lock); - ttm_eu_list_ref_sub(list); - return ret; + goto err; }
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; + ret = -EBUSY; + goto err; } }
@@ -194,6 +177,12 @@ retry_this_bo: ttm_eu_list_ref_sub(list);
return 0; + +err: + ttm_eu_backoff_reservation_locked(list); + spin_unlock(&glob->lru_lock); + ttm_eu_list_ref_sub(list); + return ret; } EXPORT_SYMBOL(ttm_eu_reserve_buffers);