From ca9c46c5c77987acf1bf7137bf85e9221bc459ba Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Tue, 27 Nov 2012 20:34:58 +0200 Subject: [PATCH] drm/i915: Kill i915_gem_execbuffer_wait_for_flips() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit As per Chris Wilson's suggestion make i915_gem_execbuffer_wait_for_flips() go away. This was used to stall the GPU ring while there are pending page flips involving the relevant BO. Ie. while the BO is still being scanned out by the display controller. The recommended alternative is to use the page flip events to wait for the page flips to fully complete before reusing the BO of the old front buffer. Or use more buffers. Signed-off-by: Ville Syrjälä Reviewed-by: Chris Wilson Acked-by: Kristian Høgsberg Acked-by: Jesse Barnes [danvet: don't remove obj->pending_flips, still required due to reorder patches.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 42 ---------------------- drivers/gpu/drm/i915/intel_display.c | 7 ---- 2 files changed, 49 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index ee8f97f0539e..802d925b2b57 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -601,45 +601,12 @@ err: return ret; } -static int -i915_gem_execbuffer_wait_for_flips(struct intel_ring_buffer *ring, u32 flips) -{ - u32 plane, flip_mask; - int ret; - - /* Check for any pending flips. As we only maintain a flip queue depth - * of 1, we can simply insert a WAIT for the next display flip prior - * to executing the batch and avoid stalling the CPU. - */ - - for (plane = 0; flips >> plane; plane++) { - if (((flips >> plane) & 1) == 0) - continue; - - if (plane) - flip_mask = MI_WAIT_FOR_PLANE_B_FLIP; - else - flip_mask = MI_WAIT_FOR_PLANE_A_FLIP; - - ret = intel_ring_begin(ring, 2); - if (ret) - return ret; - - intel_ring_emit(ring, MI_WAIT_FOR_EVENT | flip_mask); - intel_ring_emit(ring, MI_NOOP); - intel_ring_advance(ring); - } - - return 0; -} - static int i915_gem_execbuffer_move_to_gpu(struct intel_ring_buffer *ring, struct list_head *objects) { struct drm_i915_gem_object *obj; uint32_t flush_domains = 0; - uint32_t flips = 0; int ret; list_for_each_entry(obj, objects, exec_list) { @@ -650,18 +617,9 @@ i915_gem_execbuffer_move_to_gpu(struct intel_ring_buffer *ring, if (obj->base.write_domain & I915_GEM_DOMAIN_CPU) i915_gem_clflush_object(obj); - if (obj->base.pending_write_domain) - flips |= atomic_read(&obj->pending_flip); - flush_domains |= obj->base.write_domain; } - if (flips) { - ret = i915_gem_execbuffer_wait_for_flips(ring, flips); - if (ret) - return ret; - } - if (flush_domains & I915_GEM_DOMAIN_CPU) i915_gem_chipset_flush(ring->dev); diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 78d12c471472..8cdf3a1226dc 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -6945,8 +6945,6 @@ static void do_intel_finish_page_flip(struct drm_device *dev, obj = work->old_fb_obj; - atomic_clear_mask(1 << intel_crtc->plane, - &obj->pending_flip.counter); wake_up(&dev_priv->pending_flip_queue); queue_work(dev_priv->wq, &work->work); @@ -7292,10 +7290,6 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, work->enable_stall_check = true; - /* Block clients from rendering to the new back buffer until - * the flip occurs and the object is no longer visible. - */ - atomic_add(1 << intel_crtc->plane, &work->old_fb_obj->pending_flip); atomic_inc(&intel_crtc->unpin_work_count); ret = dev_priv->display.queue_flip(dev, crtc, fb, obj); @@ -7312,7 +7306,6 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, cleanup_pending: atomic_dec(&intel_crtc->unpin_work_count); - atomic_sub(1 << intel_crtc->plane, &work->old_fb_obj->pending_flip); drm_gem_object_unreference(&work->old_fb_obj->base); drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex); -- 2.20.1