50 lines
1.5 KiB
Rust
50 lines
1.5 KiB
Rust
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// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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//! 1:1 Task bookeeping
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//!
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//! This module keeps track of the number of running 1:1 tasks so that entry
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//! points with libnative know when it's possible to exit the program (once all
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//! tasks have exited).
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//!
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//! The green counterpart for this is bookeeping on sched pools.
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use std::sync::atomics;
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use std::unstable::mutex::{Mutex, MUTEX_INIT};
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static mut TASK_COUNT: atomics::AtomicUint = atomics::INIT_ATOMIC_UINT;
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static mut TASK_LOCK: Mutex = MUTEX_INIT;
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pub fn increment() {
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unsafe { TASK_COUNT.fetch_add(1, atomics::SeqCst); }
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}
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pub fn decrement() {
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unsafe {
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if TASK_COUNT.fetch_sub(1, atomics::SeqCst) == 1 {
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TASK_LOCK.lock();
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TASK_LOCK.signal();
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TASK_LOCK.unlock();
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}
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}
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}
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/// Waits for all other native tasks in the system to exit. This is only used by
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/// the entry points of native programs
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pub fn wait_for_other_tasks() {
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unsafe {
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TASK_LOCK.lock();
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while TASK_COUNT.load(atomics::SeqCst) > 0 {
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TASK_LOCK.wait();
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}
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TASK_LOCK.unlock();
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}
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}
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