From 1f727d9e725a408ef58d159c20fb2e51818ff153 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 21 Jul 2017 15:50:36 +0100 Subject: [PATCH] drm/i915: Only skip updating execobject.offset after error I was being overly paranoid in not updating the execobject.offset after performing the fallback copy where we set reloc.presumed_offset to -1. The thinking was to ensure that a subsequent NORELOC execbuf would be forced to process the invalid relocations. However this is overkill so long as we *only* update the execobject.offset following a successful update of the relocation value witin the batch. If we have to repeat the execbuf due to a later interruption, then we may skip the relocations on the second pass (honouring NORELOC) since the execobject.offset match the actual offsets (even though reloc.presumed_offset is garbage). Subsequent calls to execbuf with NORELOC should themselves ensure that the reloc.presumed_offset have been corrected in case of future migration. Reporting back the actual execobject.offset, even when reloc.presumed_offset is garbage, ensures that reuse of those objects use the latest information to avoid relocations. Fixes: 2889caa92321 ("drm/i915: Eliminate lots of iterations over the execobjects array") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101635 Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Cc: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20170721145037.25105-4-chris@chris-wilson.co.uk Reviewed-by: Joonas Lahtinen Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index f30675c..ae47e18 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -1776,7 +1776,7 @@ out: } } - return err ?: have_copy; + return err; } static int eb_relocate(struct i915_execbuffer *eb) @@ -2210,7 +2210,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, goto err_rpm; err = eb_relocate(&eb); - if (err) + if (err) { /* * If the user expects the execobject.offset and * reloc.presumed_offset to be an exact match, @@ -2219,8 +2219,8 @@ i915_gem_do_execbuffer(struct drm_device *dev, * relocation. */ args->flags &= ~__EXEC_HAS_RELOC; - if (err < 0) goto err_vma; + } if (unlikely(eb.batch->exec_entry->flags & EXEC_OBJECT_WRITE)) { DRM_DEBUG("Attempting to use self-modifying batch buffer\n"); -- 2.7.4