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dc5dbd5542
I wanted to add an environmental variable to disable the style sharing cache for gecko, but the current pattern involves lazy_static!, which involves an atomic operation on lookup, which is a bit hot to do each time we try to share styles. This makes that work happen once per process.
55 lines
1.6 KiB
Rust
55 lines
1.6 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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//! Global style data
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use context::StyleSystemOptions;
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use num_cpus;
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use rayon;
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use shared_lock::SharedRwLock;
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use std::cmp;
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use std::env;
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/// Global style data
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pub struct GlobalStyleData {
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/// How many threads parallel styling can use.
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pub num_threads: usize,
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/// The parallel styling thread pool.
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pub style_thread_pool: Option<rayon::ThreadPool>,
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/// Shared RWLock for CSSOM objects
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pub shared_lock: SharedRwLock,
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/// Global style system options determined by env vars.
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pub options: StyleSystemOptions,
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}
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lazy_static! {
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/// Global style data
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pub static ref GLOBAL_STYLE_DATA: GlobalStyleData = {
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let stylo_threads = env::var("STYLO_THREADS")
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.map(|s| s.parse::<usize>().expect("invalid STYLO_THREADS value"));
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let num_threads = match stylo_threads {
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Ok(num) => num,
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_ => cmp::max(num_cpus::get() * 3 / 4, 1),
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};
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let pool = if num_threads <= 1 {
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None
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} else {
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let configuration =
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rayon::Configuration::new().set_num_threads(num_threads);
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let pool = rayon::ThreadPool::new(configuration).ok();
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pool
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};
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GlobalStyleData {
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num_threads: num_threads,
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style_thread_pool: pool,
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shared_lock: SharedRwLock::new(),
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options: StyleSystemOptions::default(),
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}
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};
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}
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