From 630a9d4255c3fa0eecb69229be97df2d04e36f0a Mon Sep 17 00:00:00 2001 From: Martin Robinson Date: Fri, 19 Feb 2016 14:52:56 -0800 Subject: [PATCH] Remove parallel display list construction Parallel display list construction hasn't been shown to give any performance gains. It is also incompatible with the current flat display list implementation. Once flat display lists have landed, we can explore possible benefits of parallel construction once again. --- components/layout/layout_thread.rs | 14 +------ components/layout/parallel.rs | 60 +----------------------------- components/util/opts.rs | 9 ----- 3 files changed, 3 insertions(+), 80 deletions(-) diff --git a/components/layout/layout_thread.rs b/components/layout/layout_thread.rs index fbc1cd26daf..98aebbcf47f 100644 --- a/components/layout/layout_thread.rs +++ b/components/layout/layout_thread.rs @@ -855,19 +855,7 @@ impl LayoutThread { flow::mut_base(flow_ref::deref_mut(layout_root)).clip = ClippingRegion::from_rect(&data.page_clip_rect); - match (&mut self.parallel_traversal, opts::get().parallel_display_list_building) { - (&mut Some(ref mut traversal), true) => { - parallel::build_display_list_for_subtree(layout_root, - metadata, - sender, - shared_layout_context, - traversal); - } - _ => { - sequential::build_display_list_for_subtree(layout_root, - shared_layout_context); - } - } + sequential::build_display_list_for_subtree(layout_root, shared_layout_context); if data.goal == ReflowGoal::ForDisplay { debug!("Done building display list."); diff --git a/components/layout/parallel.rs b/components/layout/parallel.rs index 4ea427b11ee..39986d86580 100644 --- a/components/layout/parallel.rs +++ b/components/layout/parallel.rs @@ -17,8 +17,8 @@ use std::sync::atomic::{AtomicIsize, Ordering}; use style::dom::{TNode, UnsafeNode}; use style::parallel::{CHUNK_SIZE, WorkQueueData}; use style::parallel::{run_queue_with_custom_work_data_type}; -use traversal::{AssignBSizesAndStoreOverflow, AssignISizes, BubbleISizes}; -use traversal::{BuildDisplayList, ComputeAbsolutePositions, PostorderNodeMutTraversal}; +use traversal::AssignBSizesAndStoreOverflow; +use traversal::{AssignISizes, BubbleISizes, PostorderNodeMutTraversal}; use util::opts; use util::workqueue::{WorkQueue, WorkUnit, WorkerProxy}; @@ -200,23 +200,6 @@ impl<'a> ParallelPreorderFlowTraversal for AssignISizes<'a> { impl<'a> ParallelPostorderFlowTraversal for AssignBSizesAndStoreOverflow<'a> {} -impl<'a> ParallelPreorderFlowTraversal for ComputeAbsolutePositions<'a> { - fn run_parallel(&self, - unsafe_flows: UnsafeFlowList, - proxy: &mut WorkerProxy) { - self.run_parallel_helper(unsafe_flows, - proxy, - compute_absolute_positions, - build_display_list) - } - - fn should_record_thread_ids(&self) -> bool { - false - } -} - -impl<'a> ParallelPostorderFlowTraversal for BuildDisplayList<'a> {} - fn assign_inline_sizes(unsafe_flows: UnsafeFlowList, proxy: &mut WorkerProxy) { let shared_layout_context = proxy.user_data(); @@ -237,28 +220,6 @@ fn assign_block_sizes_and_store_overflow( assign_block_sizes_traversal.run_parallel(unsafe_flow) } -fn compute_absolute_positions( - unsafe_flows: UnsafeFlowList, - proxy: &mut WorkerProxy) { - let shared_layout_context = proxy.user_data(); - let layout_context = LayoutContext::new(shared_layout_context); - let compute_absolute_positions_traversal = ComputeAbsolutePositions { - layout_context: &layout_context, - }; - compute_absolute_positions_traversal.run_parallel(unsafe_flows, proxy); -} - -fn build_display_list(unsafe_flow: UnsafeFlow, - shared_layout_context: &SharedLayoutContext) { - let layout_context = LayoutContext::new(shared_layout_context); - - let build_display_list_traversal = BuildDisplayList { - layout_context: &layout_context, - }; - - build_display_list_traversal.run_parallel(unsafe_flow); -} - pub fn traverse_flow_tree_preorder( root: &mut FlowRef, profiler_metadata: Option, @@ -281,20 +242,3 @@ pub fn traverse_flow_tree_preorder( }); }, shared_layout_context); } - -pub fn build_display_list_for_subtree( - root: &mut FlowRef, - profiler_metadata: Option, - time_profiler_chan: time::ProfilerChan, - shared_layout_context: &SharedLayoutContext, - queue: &mut WorkQueue) { - run_queue_with_custom_work_data_type(queue, |queue| { - profile(time::ProfilerCategory::LayoutParallelWarmup, profiler_metadata, - time_profiler_chan, || { - queue.push(WorkUnit { - fun: compute_absolute_positions, - data: (box vec![mut_owned_flow_to_unsafe_flow(root)], 0), - }) - }); - }, shared_layout_context); -} diff --git a/components/util/opts.rs b/components/util/opts.rs index d2dbdc1c382..90135fb78ca 100644 --- a/components/util/opts.rs +++ b/components/util/opts.rs @@ -169,9 +169,6 @@ pub struct Opts { /// Whether Style Sharing Cache is used pub disable_share_style_cache: bool, - /// Whether to run absolute position calculation and display list construction in parallel. - pub parallel_display_list_building: bool, - /// Translate mouse input into touch events. pub convert_mouse_to_touch: bool, @@ -263,9 +260,6 @@ pub struct DebugOptions { /// Disable the style sharing cache. pub disable_share_style_cache: bool, - /// Build display lists in parallel. - pub parallel_display_list_building: bool, - /// Translate mouse input into touch events. pub convert_mouse_to_touch: bool, @@ -316,7 +310,6 @@ impl DebugOptions { "trace-layout" => debug_options.trace_layout = true, "validate-display-list-geometry" => debug_options.validate_display_list_geometry = true, "disable-share-style-cache" => debug_options.disable_share_style_cache = true, - "parallel-display-list-building" => debug_options.parallel_display_list_building = true, "convert-mouse-to-touch" => debug_options.convert_mouse_to_touch = true, "replace-surrogates" => debug_options.replace_surrogates = true, "gc-profile" => debug_options.gc_profile = true, @@ -497,7 +490,6 @@ pub fn default_opts() -> Opts { profile_script_events: false, profile_heartbeats: false, disable_share_style_cache: false, - parallel_display_list_building: false, convert_mouse_to_touch: false, exit_after_load: false, no_native_titlebar: false, @@ -737,7 +729,6 @@ pub fn from_cmdline_args(args: &[String]) -> ArgumentParsingResult { relayout_event: debug_options.relayout_event, validate_display_list_geometry: debug_options.validate_display_list_geometry, disable_share_style_cache: debug_options.disable_share_style_cache, - parallel_display_list_building: debug_options.parallel_display_list_building, convert_mouse_to_touch: debug_options.convert_mouse_to_touch, exit_after_load: opt_match.opt_present("x"), no_native_titlebar: opt_match.opt_present("b"),