From 8489f30e0c8e47d2d654cfb31825ff37de7e5574 Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Thu, 15 Jun 2023 18:20:52 +0100 Subject: [PATCH] drm/xe/bo: handle PL_TT -> PL_TT MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When moving between PL_VRAM <-> PL_SYSTEM we have to have use PL_TT in the middle as a temporary resource for the actual copy. In some GL workloads it can be seen that once the resource has been moved to the PL_TT we might have to bail out of the ttm_bo_validate(), before finishing the final hop. If this happens the resource is left as TTM_PL_FLAG_TEMPORARY, and when the ttm_bo_validate() is restarted the current placement is always seen as incompatible, requiring us to complete the move. However if the BO allows PL_TT as a possible placement we can end up attempting a PL_TT -> PL_TT move (like when running out of VRAM) which leads to explosions in xe_bo_move(), like triggering the XE_BUG_ON(!tile). Going from TTM_PL_FLAG_TEMPORARY with PL_TT -> PL_VRAM should already work as-is, so it looks like we only need to worry about PL_TT -> PL_TT and it looks like we can just treat it as a dummy move, since no real move is needed. Reported-by: José Roberto de Souza Signed-off-by: Matthew Auld Cc: Thomas Hellström Reviewed-by: Thomas Hellström Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/xe/xe_bo.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 43801994f069d..ad0ea3014bfee 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -603,6 +603,16 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, goto out; } + /* + * Failed multi-hop where the old_mem is still marked as + * TTM_PL_FLAG_TEMPORARY, should just be a dummy move. + */ + if (old_mem->mem_type == XE_PL_TT && + new_mem->mem_type == XE_PL_TT) { + ttm_bo_move_null(ttm_bo, new_mem); + goto out; + } + if (!move_lacks_source && !xe_bo_is_pinned(bo)) { ret = xe_bo_move_notify(bo, ctx); if (ret) -- 2.30.2