forked from mirrors/gecko-dev
		
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			<!-- Please describe your changes on the following line: --> Before this PR, every object reflected in CSSOM is in `Arc<RwLock<_>>` to enable safe (synchronized) mutable aliasing. Acquiring all these locks has significant cost during selector matching: * https://bugzilla.mozilla.org/show_bug.cgi?id=1311469 * https://bugzilla.mozilla.org/show_bug.cgi?id=1335941 * https://bugzilla.mozilla.org/show_bug.cgi?id=1339703 This PR introduce a mechanism to protect many objects with the same `RwLock` that only needs to be acquired once. In Stylo, there is one such lock per process (in a `lazy_static`), used for everything. I non-Stylo Servo, I originally intended to have one such lock per document (for author-origin stylesheets, and one per process for user-agent and user sytlesheets since they’re shared across documents, and never mutated anyway). However I failed to have the same document-specific (or pipeline-specific) `Arc` reachable from both `Document` nodes and `LayoutThread`. Recursively following callers lead me to include this `Arc` in `UnprivilegedPipelineContent`, but that needs to be serializable. So there is a second process-wide lock. This was previously #15998, closed accidentally. --- <!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: --> - [x] `./mach build -d` does not report any errors - [x] `./mach test-tidy` does not report any errors - [ ] These changes fix #__ (github issue number if applicable). <!-- Either: --> - [ ] There are tests for these changes OR - [ ] These changes do not require tests because _____ <!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. --> Source-Repo: https://github.com/servo/servo Source-Revision: bb54f0a429de0e8b8861f8071b6cf82f73622664 --HG-- extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear extra : subtree_revision : 851230e57ac8775707df5f0f103be5feac81fc41
		
			
				
	
	
		
			61 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			61 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| /* This Source Code Form is subject to the terms of the Mozilla Public
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|  * License, v. 2.0. If a copy of the MPL was not distributed with this
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|  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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| 
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| use dom::bindings::codegen::Bindings::CSSConditionRuleBinding::CSSConditionRuleMethods;
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| use dom::bindings::inheritance::Castable;
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| use dom::bindings::str::DOMString;
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| use dom::cssgroupingrule::CSSGroupingRule;
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| use dom::cssmediarule::CSSMediaRule;
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| use dom::cssstylesheet::CSSStyleSheet;
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| use dom::csssupportsrule::CSSSupportsRule;
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| use dom_struct::dom_struct;
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| use std::sync::Arc;
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| use style::shared_lock::{SharedRwLock, Locked};
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| use style::stylesheets::CssRules as StyleCssRules;
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| 
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| #[dom_struct]
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| pub struct CSSConditionRule {
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|     cssgroupingrule: CSSGroupingRule,
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| }
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| 
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| impl CSSConditionRule {
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|     pub fn new_inherited(parent_stylesheet: &CSSStyleSheet,
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|                          rules: Arc<Locked<StyleCssRules>>) -> CSSConditionRule {
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|         CSSConditionRule {
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|             cssgroupingrule: CSSGroupingRule::new_inherited(parent_stylesheet, rules),
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|         }
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|     }
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| 
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|     pub fn parent_stylesheet(&self) -> &CSSStyleSheet {
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|         self.cssgroupingrule.parent_stylesheet()
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|     }
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| 
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|     pub fn shared_lock(&self) -> &SharedRwLock {
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|         self.cssgroupingrule.shared_lock()
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|     }
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| }
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| 
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| impl CSSConditionRuleMethods for CSSConditionRule {
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|     /// https://drafts.csswg.org/css-conditional-3/#dom-cssconditionrule-conditiontext
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|     fn ConditionText(&self) -> DOMString {
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|         if let Some(rule) = self.downcast::<CSSMediaRule>() {
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|             rule.get_condition_text()
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|         } else if let Some(rule) = self.downcast::<CSSSupportsRule>() {
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|             rule.get_condition_text()
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|         } else {
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|             unreachable!()
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|         }
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|     }
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| 
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|     /// https://drafts.csswg.org/css-conditional-3/#dom-cssconditionrule-conditiontext
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|     fn SetConditionText(&self, text: DOMString) {
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|         if let Some(rule) = self.downcast::<CSSMediaRule>() {
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|             rule.set_condition_text(text)
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|         } else if let Some(rule) = self.downcast::<CSSSupportsRule>() {
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|             rule.set_condition_text(text)
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|         } else {
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|             unreachable!()
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|         }
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|     }
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| }
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