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Reduce the amount of comments in call_inner

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This commit is contained in:
Paul Dicker 2019-10-23 11:02:20 +02:00
parent 2e8eb5f33d
commit 4b8da9ccd5
1 changed files with 6 additions and 19 deletions
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25
src/libstd/sync/once.rs
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@ -355,25 +355,16 @@ impl Once {
// performance difference really does not matter there, and
// SeqCst minimizes the chances of something going wrong.
let mut state_and_queue = self.state_and_queue.load(Ordering::SeqCst);
loop {
match state_and_queue {
// If we're complete, then there's nothing to do, we just
// jettison out as we shouldn't run the closure.
COMPLETE => return,
// If we're poisoned and we're not in a mode to ignore
// poisoning, then we panic here to propagate the poison.
COMPLETE => break,
POISONED if !ignore_poisoning => {
// Panic to propagate the poison.
panic!("Once instance has previously been poisoned");
}
// Otherwise if we see a poisoned or otherwise incomplete state
// we will attempt to move ourselves into the RUNNING state. If
// we succeed, then the queue of waiters starts at null (all 0
// bits).
POISONED |
INCOMPLETE => {
// Try to register this thread as the one RUNNING.
let old = self.state_and_queue.compare_and_swap(state_and_queue,
RUNNING,
Ordering::SeqCst);
@ -391,15 +382,11 @@ impl Once {
// poisoned or not.
init(state_and_queue == POISONED);
waiter_queue.set_state_on_drop_to = COMPLETE;
return
break
}
// All other values we find should correspond to the RUNNING
// state with an encoded waiter list in the more significant
// bits. We attempt to enqueue ourselves by moving us to the
// head of the list and bail out if we ever see a state that's
// not RUNNING.
_ => {
// All other values must be RUNNING with possibly a
// pointer to the waiter queue in the more significant bits.
assert!(state_and_queue & STATE_MASK == RUNNING);
wait(&self.state_and_queue, state_and_queue);
state_and_queue = self.state_and_queue.load(Ordering::SeqCst);