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Modify CloudABI ReentrantMutex to use MaybeUninit

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Remove uses of mem::uninitialized, which is now deprecated
This commit is contained in:
Nathan 2019-07-22 17:31:35 -04:00
parent e1e0df8a49
commit 82dd54baf3
1 changed files with 18 additions and 14 deletions
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32
src/libstd/sys/cloudabi/mutex.rs
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@ -1,5 +1,6 @@
use crate::cell::UnsafeCell;
use crate::mem;
use crate::mem::MaybeUninit;
use crate::sync::atomic::{AtomicU32, Ordering};
use crate::sys::cloudabi::abi;
use crate::sys::rwlock::{self, RWLock};
@ -47,25 +48,28 @@ impl Mutex {
}
pub struct ReentrantMutex {
lock: UnsafeCell<AtomicU32>,
recursion: UnsafeCell<u32>,
lock: UnsafeCell<MaybeUninit<AtomicU32>>,
recursion: UnsafeCell<MaybeUninit<u32>>,
}
impl ReentrantMutex {
pub unsafe fn uninitialized() -> ReentrantMutex {
mem::uninitialized()
ReentrantMutex {
lock: UnsafeCell::new(MaybeUninit::uninit()),
recursion: UnsafeCell::new(MaybeUninit::uninit())
}
}
pub unsafe fn init(&mut self) {
self.lock = UnsafeCell::new(AtomicU32::new(abi::LOCK_UNLOCKED.0));
self.recursion = UnsafeCell::new(0);
self.lock = UnsafeCell::new(MaybeUninit::new(AtomicU32::new(abi::LOCK_UNLOCKED.0)));
self.recursion = UnsafeCell::new(MaybeUninit::new(0));
}
pub unsafe fn try_lock(&self) -> bool {
// Attempt to acquire the lock.
let lock = self.lock.get();
let recursion = self.recursion.get();
if let Err(old) = (*lock).compare_exchange(
if let Err(old) = (*(*lock).as_mut_ptr()).compare_exchange(
abi::LOCK_UNLOCKED.0,
__pthread_thread_id.0 | abi::LOCK_WRLOCKED.0,
Ordering::Acquire,
@ -74,14 +78,14 @@ impl ReentrantMutex {
// If we fail to acquire the lock, it may be the case
// that we've already acquired it and may need to recurse.
if old & !abi::LOCK_KERNEL_MANAGED.0 == __pthread_thread_id.0 | abi::LOCK_WRLOCKED.0 {
*recursion += 1;
*(*recursion).as_mut_ptr() += 1;
true
} else {
false
}
} else {
// Success.
assert_eq!(*recursion, 0, "Mutex has invalid recursion count");
assert_eq!(*(*recursion).as_mut_ptr(), 0, "Mutex has invalid recursion count");
true
}
}
@ -112,14 +116,14 @@ impl ReentrantMutex {
let lock = self.lock.get();
let recursion = self.recursion.get();
assert_eq!(
(*lock).load(Ordering::Relaxed) & !abi::LOCK_KERNEL_MANAGED.0,
(*(*lock).as_mut_ptr()).load(Ordering::Relaxed) & !abi::LOCK_KERNEL_MANAGED.0,
__pthread_thread_id.0 | abi::LOCK_WRLOCKED.0,
"This mutex is locked by a different thread"
);
if *recursion > 0 {
*recursion -= 1;
} else if !(*lock)
if *(*recursion).as_mut_ptr() > 0 {
*(*recursion).as_mut_ptr() -= 1;
} else if !(*(*lock).as_mut_ptr())
.compare_exchange(
__pthread_thread_id.0 | abi::LOCK_WRLOCKED.0,
abi::LOCK_UNLOCKED.0,
@ -139,10 +143,10 @@ impl ReentrantMutex {
let lock = self.lock.get();
let recursion = self.recursion.get();
assert_eq!(
(*lock).load(Ordering::Relaxed),
(*(*lock).as_mut_ptr()).load(Ordering::Relaxed),
abi::LOCK_UNLOCKED.0,
"Attempted to destroy locked mutex"
);
assert_eq!(*recursion, 0, "Recursion counter invalid");
assert_eq!(*(*recursion).as_mut_ptr(), 0, "Recursion counter invalid");
}
}