From: Chris Wilson chris@chris-wilson.co.uk
commit 761c70a52586a9214b29026d384d2c01b73661a8 upstream.
Simplify the frontbuffer unpin by removing the lock requirement. The LRU bumping was primarily to protect the GTT from being evicted and from frontbuffers being eagerly shrunk. Now we protect frontbuffers from the shrinker, and we avoid accidentally evicting from the GTT, so the benefit from bumping LRU is no more, and we can save more time by not.
Reported-and-tested-by: Matti Hämäläinen ccr@tnsp.org Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2905 Fixes: c1793ba86a41 ("drm/i915: Add ww locking to pin_to_display_plane, v2.") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Matthew Auld matthew.auld@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20210119214336.1463-6-chris@ch... (cherry picked from commit 14ca83eece9565a2d2177291ceb122982dc38420) Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Jani Nikula jani.nikula@intel.com Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_display.c | 7 +--- drivers/gpu/drm/i915/display/intel_overlay.c | 4 +- drivers/gpu/drm/i915/gem/i915_gem_domain.c | 45 --------------------------- drivers/gpu/drm/i915/gem/i915_gem_object.h | 1 4 files changed, 4 insertions(+), 53 deletions(-)
--- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -2294,7 +2294,7 @@ intel_pin_and_fence_fb_obj(struct drm_fr */ ret = i915_vma_pin_fence(vma); if (ret != 0 && INTEL_GEN(dev_priv) < 4) { - i915_gem_object_unpin_from_display_plane(vma); + i915_vma_unpin(vma); vma = ERR_PTR(ret); goto err; } @@ -2312,12 +2312,9 @@ err:
void intel_unpin_fb_vma(struct i915_vma *vma, unsigned long flags) { - i915_gem_object_lock(vma->obj, NULL); if (flags & PLANE_HAS_FENCE) i915_vma_unpin_fence(vma); - i915_gem_object_unpin_from_display_plane(vma); - i915_gem_object_unlock(vma->obj); - + i915_vma_unpin(vma); i915_vma_put(vma); }
--- a/drivers/gpu/drm/i915/display/intel_overlay.c +++ b/drivers/gpu/drm/i915/display/intel_overlay.c @@ -359,7 +359,7 @@ static void intel_overlay_release_old_vm intel_frontbuffer_flip_complete(overlay->i915, INTEL_FRONTBUFFER_OVERLAY(overlay->crtc->pipe));
- i915_gem_object_unpin_from_display_plane(vma); + i915_vma_unpin(vma); i915_vma_put(vma); }
@@ -860,7 +860,7 @@ static int intel_overlay_do_put_image(st return 0;
out_unpin: - i915_gem_object_unpin_from_display_plane(vma); + i915_vma_unpin(vma); out_pin_section: atomic_dec(&dev_priv->gpu_error.pending_fb_pin);
--- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c @@ -387,48 +387,6 @@ err: return vma; }
-static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj) -{ - struct drm_i915_private *i915 = to_i915(obj->base.dev); - struct i915_vma *vma; - - if (list_empty(&obj->vma.list)) - return; - - mutex_lock(&i915->ggtt.vm.mutex); - spin_lock(&obj->vma.lock); - for_each_ggtt_vma(vma, obj) { - if (!drm_mm_node_allocated(&vma->node)) - continue; - - GEM_BUG_ON(vma->vm != &i915->ggtt.vm); - list_move_tail(&vma->vm_link, &vma->vm->bound_list); - } - spin_unlock(&obj->vma.lock); - mutex_unlock(&i915->ggtt.vm.mutex); - - if (i915_gem_object_is_shrinkable(obj)) { - unsigned long flags; - - spin_lock_irqsave(&i915->mm.obj_lock, flags); - - if (obj->mm.madv == I915_MADV_WILLNEED && - !atomic_read(&obj->mm.shrink_pin)) - list_move_tail(&obj->mm.link, &i915->mm.shrink_list); - - spin_unlock_irqrestore(&i915->mm.obj_lock, flags); - } -} - -void -i915_gem_object_unpin_from_display_plane(struct i915_vma *vma) -{ - /* Bump the LRU to try and avoid premature eviction whilst flipping */ - i915_gem_object_bump_inactive_ggtt(vma->obj); - - i915_vma_unpin(vma); -} - /** * Moves a single object to the CPU read, and possibly write domain. * @obj: object to act on @@ -569,9 +527,6 @@ i915_gem_set_domain_ioctl(struct drm_dev else err = i915_gem_object_set_to_cpu_domain(obj, write_domain);
- /* And bump the LRU for this access */ - i915_gem_object_bump_inactive_ggtt(obj); - i915_gem_object_unlock(obj);
if (write_domain) --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -471,7 +471,6 @@ i915_gem_object_pin_to_display_plane(str u32 alignment, const struct i915_ggtt_view *view, unsigned int flags); -void i915_gem_object_unpin_from_display_plane(struct i915_vma *vma);
void i915_gem_object_make_unshrinkable(struct drm_i915_gem_object *obj); void i915_gem_object_make_shrinkable(struct drm_i915_gem_object *obj);