pub struct WaitGroup { /* private fields */ }
Expand description
Enables threads to synchronize the beginning or end of some computation.
§Wait groups vs barriers
WaitGroup
is very similar to Barrier
, but there are a few differences:
-
Barrier
needs to know the number of threads at construction, whileWaitGroup
is cloned to register more threads. -
A
Barrier
can be reused even after all threads have synchronized, while aWaitGroup
synchronizes threads only once. -
All threads wait for others to reach the
Barrier
. WithWaitGroup
, each thread can choose to either wait for other threads or to continue without blocking.
§Examples
use crossbeam_utils::sync::WaitGroup;
use std::thread;
// Create a new wait group.
let wg = WaitGroup::new();
for _ in 0..4 {
// Create another reference to the wait group.
let wg = wg.clone();
thread::spawn(move || {
// Do some work.
// Drop the reference to the wait group.
drop(wg);
});
}
// Block until all threads have finished their work.
wg.wait();
Implementations§
source§impl WaitGroup
impl WaitGroup
sourcepub fn new() -> WaitGroup
pub fn new() -> WaitGroup
Creates a new wait group and returns the single reference to it.
§Examples
use crossbeam_utils::sync::WaitGroup;
let wg = WaitGroup::new();
sourcepub fn wait(self)
pub fn wait(self)
Drops this reference and waits until all other references are dropped.
§Examples
use crossbeam_utils::sync::WaitGroup;
use std::thread;
let wg = WaitGroup::new();
thread::spawn({
let wg = wg.clone();
move || {
// Block until both threads have reached `wait()`.
wg.wait();
}
});
// Block until both threads have reached `wait()`.
wg.wait();
Trait Implementations§
Auto Trait Implementations§
impl Freeze for WaitGroup
impl RefUnwindSafe for WaitGroup
impl Send for WaitGroup
impl Sync for WaitGroup
impl Unpin for WaitGroup
impl UnwindSafe for WaitGroup
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)