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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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https://github.com/servo/rust-cssparser/pull/123
In particular, `match_ignore_ascii_case` now supports the full `match` syntax.
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<s>Depends on https://github.com/servo/rust-cssparser/pull/122.</s>
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By having a single thread pool, rather than one per document, we use less memory. This addresses https://bugzilla.mozilla.org/show_bug.cgi?id=1324250.
This may be obvious to an experienced Rust programmer, but I went with raw pointers because trying to use `Option` global variables resulted in complaints about turning on feature flags in nightly Rust. Since this is for stylo, nightly features are not appropriate here.
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I have been working on issue number #15244. I have substituted quickersort with pdqsort in the style component. The changes I made affect: Cargo.toml, stylist.rs and lib.rs (all of them are in /components/style).
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The idea here is having (for convenience) different `Expression` and `Device` representations for Gecko.
Both will be implemented in rust, but will use `nsMediaFeatures` as a source of media features instead of the Servo bits.
Does it sound good?
r? @heycam or @Manishearth
Source-Repo: https://github.com/servo/servo
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While reviewing @bzbarsky's patches in [1], I started typing out some lore about how mutable AtomicRefCell borrows are actually cheaper than immutable ones, so we should prefer them where possible. But then I decided that this was a really dumb state of affairs and that we should just fix AtomicRefCell instead, and implement a proper AtomicRef{,Mut}::map while we were at it. So here we are.
This PR adds a from-scratch implementation of AtomicRefCell that aims to be 100% sound, even in unrealistic overflow scenarios. We should probably get this on crates.io eventually, but I want to land it landed in-tree first.
With this implementation, each operation (borrow or release) is one atomic instruction, and all borrow/release pairs (mutable or immutable) take 12 ns on my machine, which is what I'd expect. This is a 50% improvement over the previous implementation in the immutable case.
There may be some places where we could get away with Ordering::Release instead of Ordering::AcqRel, but it didn't seem worth it to try to reason it out.
r? @Manishearth
CC @emilio @SimonSapin @heycam @upsuper
[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1298588
Source-Repo: https://github.com/servo/servo
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Style no forced docs for the properties code and similar, but I ran out of time, and I think it's a nice improvement.
I'd appreciate a fast-ish turn-around time because this is pretty much prone to bitrot.
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With this PR, the only remaining usage of UnsafeNode is the transition stuff, which is servo-only and probably going to be rewritten over the course of stylo. The parallel traversal is now fully typechecked and safe. \o/
r? @emilio
Source-Repo: https://github.com/servo/servo
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See the discussion in https://bugzilla.mozilla.org/show_bug.cgi?id=1323372
@emilio Please review, but don't merge yet until we get the upstream changes into Rayon.
CC @SimonSapin @heycam @upsuper @Manishearth @pcwalton @nikomatsakis
Source-Repo: https://github.com/servo/servo
Source-Revision: 8fd8d6161426af386c0dfd3d13968a409474eb16
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This PR removes the `util` crate.
* Replaced the `spawn_named` and `clamp` functions by appropriate uses of `std:🧵:Builder::spawn`, `std::cmp::min` and `std::cmp::max`.
* Moved `opts`, `prefs` and `resource_files` into a new `config` crate.
* Moved `remutex` and `geometry` into their own crates.
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* `LonghandId` and `ShorthandId` are C-like enums
* `Atom` is used for the name of custom properties.
* `PropertyDeclarationId` is the identifier for `PropertyDeclaration`,
after parsing and shorthand expansion. (Longhand or custom property.)
* `PropertyId` represents any CSS property, e.g. in CSSOM.
(Longhand, shorthand, or custom.)
CC @upsuper
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I think I got the numbers right, want to do a try run before just in case.
r? @SimonSapin
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Still needs a bunch of code in net to be converted in order to get more
advantage of this for images and stuff, but meanwhile this should help quite a
bit with #13778.
Still wanted to get this in.
r? @SimonSapin
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The current work queue had a really annoying constraint: The size of the node had to be the size of the work unit data.
This makes it impractical for the new restyling model where we plan to pass down a bunch of data.
Rayon by default makes you wait for the result of the work unit, which makes it impractical for the current model (it's mostly sequential).
I added an API to rayon that allows us to push work to the queue without waiting (https://github.com/nikomatsakis/rayon/pull/103).
This still needs some work (for example, we're loosing the memory reporting functionality), but I wanted feedback on this.
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This commit itself only moves things around and adds an extra parameter to the
`apply_declarations` function to eventually handle #14079 correctly.
Probably needs a more granular API to query fonts, á la nsFontMetrics, but
that's trivial to do once this is landed.
Then we should make the font provider mandatory, and implement the missing stylo
bits.
Source-Repo: https://github.com/servo/servo
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We need to hang both snapshots and restyle damage off of ElementData, and so we need them to be concrete to avoid infecting ElementData with the trait hierarchy.
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This will allow types to be generic over our local `ToCss`
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This patch introduces infrastructure for the rule tree, and constructs it.
We don't use it yet, nor have good heuristics for GC'ing it, but this should not
happen anymore once we store the rule node reference in the node.
I haven't messed up with memory orders because I want to do a try run with it,
then mess with them.
Source-Repo: https://github.com/servo/servo
Source-Revision: ac0475971bb24a63ca5d36d1d17e3036ddb99049
Previously, `string-cache` defined:
* An string-like `Atom` type,
* An `atom!("foo")` macro that expands to a value of that type, for a set of strings known at compile-time,
* A `struct Namespace(Atom);` type
* A `ns!(html)` macro that maps known prefixed to `Namespace` values with the corresponding namespace URL.
Adding a string to the static set required making a change to the `string-cache` crate.
With 0.3, the `Atom` type is now generic, with a type parameter that provides a set of static strings. We can have multiple such sets, defined in different crates. The `string_cache_codegen` crate, to be used in build scripts, generates code that defines such a set, a new atom type (a type alias for `Atom<_>` with the type parameter set), and an `atom!`-like macro.
The html5ever repository has a new `html5ever_atoms` crate that defines three such types: `Prefix`, `Namespace`, and `LocalName` (with respective `namespace_prefix!`, `namespace_url!`, and `local_name!` macros). It also defines the `ns!` macro like before.
This repository has a new `servo_atoms` crate in `components/atoms` that, for now, defines a single `Atom` type (and `atom!`) macro. (`servo_atoms::Atom` is defined as something like `type Atom = string_cache::Atom<ServoStaticStringSet>;`, so overall there’s now two types named `Atom`.)
In this PR, `servo_atoms::Atom` is used for everything else that was `string_cache::Atom` before. But more atom types can be defined as needed. Two reasons to do this are to auto-generate the set of static strings (I’m planning to do this for CSS property names, which is the motivation for this change), or to have the type system help us avoid mix up unrelated things (this is why we had a `Namespace` type ever before this change).
Introducing new types helped me find a bug: when creating a new attribute `dom::Element::set_style_attr`, would pass `Some(atom!("style"))` instead of `None` (now `Option<html5ever_atoms::Prefix>` instead of `Option<string_cache::Atom>`) to the `prefix` argument of `Attr::new`. I suppose the author of that code confused it with the `local_name` argument.
---
Note that Stylo is not affected by any of this. The `gecko_string_cache` module is unchanged, with a single `Atom` type. The `style` crate conditionally compiles `Prefix` and `LocalName` re-exports for that are both `gecko_string_cache::Atom` on stylo.
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Fixes#13376.
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Use `unicode_segmentation` crate to truncate strings on grapheme boundaries.
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test-geckolib used to do things, but almost all of geckolib has been moved to the style crate, with the tests in `tests/unit/stylo`. (`./mach test-stylo) Now test-geckolib does nothing.
Fixes#13721
r? @jdm
Source-Repo: https://github.com/servo/servo
Source-Revision: 2bb7cc227bf2a3260e3b9c4f3953ca55d93629fe
Warnings have been piling up in the style system, and making it harder to tell when new warnings are introduced. I think we should tighten up on them.
CC @emilio @Manishearth @SimonSapin @heycam @pcwalton @metajack @larsbergstrom
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As discussed in https://bugzilla.mozilla.org/show_bug.cgi?id=1305141Closes#13176
---
Original PR title: Stop relying on `impl<T: HeapSizeOf> HeapSizeOf for Arc<T>`
https://github.com/servo/heapsize/issues/37#issuecomment-249861171
This builds on top of that.
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`DOMRefCell` usage is not there year because of thread-safety questions, but I have this much already that I’d like to land before it bitrots.
r? @emilio
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(Commits do not build individually, but split up for review)
These patches make all of the background- properties accept multiple values, and add the layout code to display them.
Still needs some cleanup, and some testing, but it seems to work.
r? @SimonSapin
Source-Repo: https://github.com/servo/servo
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Have a single Vec instead of two. Fix#3426
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Fixes https://github.com/servo/servo/issues/12835
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This removes the `[replace]` override in geckolib and therefore unblocks https://github.com/servo/servo/pull/12391.
This includes the `gecko_string_cache` redesign discussed in https://github.com/servo/servo/pull/12548.
r? @bholley
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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#12548 (github issue number if applicable).
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- [ ] There are tests for these changes OR
- [x] These changes do not require new tests because refactor
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Source-Repo: https://github.com/servo/servo
Source-Revision: 5e83b3f83bfcf48d0096442bdf5c9bf753623970
