gecko-dev/servo/ports/geckolib/Cargo.toml
Simon Sapin 33a9e6d050 servo: Merge #16014 - Per-process lock for CSSOM objects (from servo:style-ref); r=emilio
<!-- 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.

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- [ ] These changes fix #__ (github issue number if applicable).

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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
2017-03-19 14:31:19 -07:00

31 lines
814 B
TOML

[package]
name = "geckoservo"
version = "0.0.1"
authors = ["The Servo Project Developers"]
license = "MPL-2.0"
[lib]
name = "geckoservo"
path = "lib.rs"
crate-type = ["staticlib", "rlib"]
[features]
bindgen = ["style/use_bindgen"]
testing = ["style/testing"]
[dependencies]
atomic_refcell = "0.1"
cssparser = "0.12"
env_logger = {version = "0.4", default-features = false} # disable `regex` to reduce code size
lazy_static = "0.2"
libc = "0.2"
log = {version = "0.3.5", features = ["release_max_level_info"]}
parking_lot = "0.3"
selectors = {path = "../../components/selectors"}
servo_url = {path = "../../components/url"}
style = {path = "../../components/style", features = ["gecko"]}
style_traits = {path = "../../components/style_traits"}
[dev-dependencies]
stylo_tests = {path = "../../tests/unit/stylo"}