diff options
Diffstat (limited to 'library/std/src/sys_common')
| -rw-r--r-- | library/std/src/sys_common/condvar.rs | 57 | ||||
| -rw-r--r-- | library/std/src/sys_common/condvar/check.rs | 58 | ||||
| -rw-r--r-- | library/std/src/sys_common/mod.rs | 3 | ||||
| -rw-r--r-- | library/std/src/sys_common/mutex.rs | 50 | ||||
| -rw-r--r-- | library/std/src/sys_common/remutex.rs | 10 | ||||
| -rw-r--r-- | library/std/src/sys_common/rwlock.rs | 71 |
6 files changed, 5 insertions, 244 deletions
diff --git a/library/std/src/sys_common/condvar.rs b/library/std/src/sys_common/condvar.rs deleted file mode 100644 index 8bc5b24115d..00000000000 --- a/library/std/src/sys_common/condvar.rs +++ /dev/null @@ -1,57 +0,0 @@ -use crate::sys::locks as imp; -use crate::sys_common::mutex::MovableMutex; -use crate::time::Duration; - -mod check; - -type CondvarCheck = <imp::MovableMutex as check::CondvarCheck>::Check; - -/// An OS-based condition variable. -pub struct Condvar { - inner: imp::MovableCondvar, - check: CondvarCheck, -} - -impl Condvar { - /// Creates a new condition variable for use. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self { inner: imp::MovableCondvar::new(), check: CondvarCheck::new() } - } - - /// Signals one waiter on this condition variable to wake up. - #[inline] - pub fn notify_one(&self) { - unsafe { self.inner.notify_one() }; - } - - /// Awakens all current waiters on this condition variable. - #[inline] - pub fn notify_all(&self) { - unsafe { self.inner.notify_all() }; - } - - /// Waits for a signal on the specified mutex. - /// - /// Behavior is undefined if the mutex is not locked by the current thread. - /// - /// May panic if used with more than one mutex. - #[inline] - pub unsafe fn wait(&self, mutex: &MovableMutex) { - self.check.verify(mutex); - self.inner.wait(mutex.raw()) - } - - /// Waits for a signal on the specified mutex with a timeout duration - /// specified by `dur` (a relative time into the future). - /// - /// Behavior is undefined if the mutex is not locked by the current thread. - /// - /// May panic if used with more than one mutex. - #[inline] - pub unsafe fn wait_timeout(&self, mutex: &MovableMutex, dur: Duration) -> bool { - self.check.verify(mutex); - self.inner.wait_timeout(mutex.raw(), dur) - } -} diff --git a/library/std/src/sys_common/condvar/check.rs b/library/std/src/sys_common/condvar/check.rs deleted file mode 100644 index 4ac9e62bf86..00000000000 --- a/library/std/src/sys_common/condvar/check.rs +++ /dev/null @@ -1,58 +0,0 @@ -use crate::ptr; -use crate::sync::atomic::{AtomicPtr, Ordering}; -use crate::sys::locks as imp; -use crate::sys_common::lazy_box::{LazyBox, LazyInit}; -use crate::sys_common::mutex::MovableMutex; - -pub trait CondvarCheck { - type Check; -} - -/// For boxed mutexes, a `Condvar` will check it's only ever used with the same -/// mutex, based on its (stable) address. -impl<T: LazyInit> CondvarCheck for LazyBox<T> { - type Check = SameMutexCheck; -} - -pub struct SameMutexCheck { - addr: AtomicPtr<()>, -} - -#[allow(dead_code)] -impl SameMutexCheck { - pub const fn new() -> Self { - Self { addr: AtomicPtr::new(ptr::null_mut()) } - } - pub fn verify(&self, mutex: &MovableMutex) { - let addr = mutex.raw() as *const imp::Mutex as *const () as *mut _; - // Relaxed is okay here because we never read through `self.addr`, and only use it to - // compare addresses. - match self.addr.compare_exchange( - ptr::null_mut(), - addr, - Ordering::Relaxed, - Ordering::Relaxed, - ) { - Ok(_) => {} // Stored the address - Err(n) if n == addr => {} // Lost a race to store the same address - _ => panic!("attempted to use a condition variable with two mutexes"), - } - } -} - -/// Unboxed mutexes may move, so `Condvar` can not require its address to stay -/// constant. -impl CondvarCheck for imp::Mutex { - type Check = NoCheck; -} - -pub struct NoCheck; - -#[allow(dead_code)] -impl NoCheck { - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self - } - pub fn verify(&self, _: &MovableMutex) {} -} diff --git a/library/std/src/sys_common/mod.rs b/library/std/src/sys_common/mod.rs index 8c19f9332dc..069b13e9d85 100644 --- a/library/std/src/sys_common/mod.rs +++ b/library/std/src/sys_common/mod.rs @@ -21,16 +21,13 @@ mod tests; pub mod backtrace; -pub mod condvar; pub mod fs; pub mod io; pub mod lazy_box; pub mod memchr; -pub mod mutex; pub mod once; pub mod process; pub mod remutex; -pub mod rwlock; pub mod thread; pub mod thread_info; pub mod thread_local_dtor; diff --git a/library/std/src/sys_common/mutex.rs b/library/std/src/sys_common/mutex.rs deleted file mode 100644 index 98046f20f89..00000000000 --- a/library/std/src/sys_common/mutex.rs +++ /dev/null @@ -1,50 +0,0 @@ -use crate::sys::locks as imp; - -/// An OS-based mutual exclusion lock. -/// -/// This mutex cleans up its resources in its `Drop` implementation, may safely -/// be moved (when not borrowed), and does not cause UB when used reentrantly. -/// -/// This mutex does not implement poisoning. -/// -/// This is either a wrapper around `LazyBox<imp::Mutex>` or `imp::Mutex`, -/// depending on the platform. It is boxed on platforms where `imp::Mutex` may -/// not be moved. -pub struct MovableMutex(imp::MovableMutex); - -unsafe impl Sync for MovableMutex {} - -impl MovableMutex { - /// Creates a new mutex. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self(imp::MovableMutex::new()) - } - - pub(super) fn raw(&self) -> &imp::Mutex { - &self.0 - } - - /// Locks the mutex blocking the current thread until it is available. - #[inline] - pub fn raw_lock(&self) { - unsafe { self.0.lock() } - } - - /// Attempts to lock the mutex without blocking, returning whether it was - /// successfully acquired or not. - #[inline] - pub fn try_lock(&self) -> bool { - unsafe { self.0.try_lock() } - } - - /// Unlocks the mutex. - /// - /// Behavior is undefined if the current thread does not actually hold the - /// mutex. - #[inline] - pub unsafe fn raw_unlock(&self) { - self.0.unlock() - } -} diff --git a/library/std/src/sys_common/remutex.rs b/library/std/src/sys_common/remutex.rs index b448ae3a997..4c054da6471 100644 --- a/library/std/src/sys_common/remutex.rs +++ b/library/std/src/sys_common/remutex.rs @@ -1,11 +1,11 @@ #[cfg(all(test, not(target_os = "emscripten")))] mod tests; -use super::mutex as sys; use crate::cell::UnsafeCell; use crate::ops::Deref; use crate::panic::{RefUnwindSafe, UnwindSafe}; use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed}; +use crate::sys::locks as sys; /// A re-entrant mutual exclusion /// @@ -39,7 +39,7 @@ use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed}; /// synchronization is left to the mutex, making relaxed memory ordering for /// the `owner` field fine in all cases. pub struct ReentrantMutex<T> { - mutex: sys::MovableMutex, + mutex: sys::Mutex, owner: AtomicUsize, lock_count: UnsafeCell<u32>, data: T, @@ -74,7 +74,7 @@ impl<T> ReentrantMutex<T> { /// Creates a new reentrant mutex in an unlocked state. pub const fn new(t: T) -> ReentrantMutex<T> { ReentrantMutex { - mutex: sys::MovableMutex::new(), + mutex: sys::Mutex::new(), owner: AtomicUsize::new(0), lock_count: UnsafeCell::new(0), data: t, @@ -100,7 +100,7 @@ impl<T> ReentrantMutex<T> { if self.owner.load(Relaxed) == this_thread { self.increment_lock_count(); } else { - self.mutex.raw_lock(); + self.mutex.lock(); self.owner.store(this_thread, Relaxed); debug_assert_eq!(*self.lock_count.get(), 0); *self.lock_count.get() = 1; @@ -162,7 +162,7 @@ impl<T> Drop for ReentrantMutexGuard<'_, T> { *self.lock.lock_count.get() -= 1; if *self.lock.lock_count.get() == 0 { self.lock.owner.store(0, Relaxed); - self.lock.mutex.raw_unlock(); + self.lock.mutex.unlock(); } } } diff --git a/library/std/src/sys_common/rwlock.rs b/library/std/src/sys_common/rwlock.rs deleted file mode 100644 index 042981dac60..00000000000 --- a/library/std/src/sys_common/rwlock.rs +++ /dev/null @@ -1,71 +0,0 @@ -use crate::sys::locks as imp; - -/// An OS-based reader-writer lock. -/// -/// This rwlock cleans up its resources in its `Drop` implementation and may -/// safely be moved (when not borrowed). -/// -/// This rwlock does not implement poisoning. -/// -/// This is either a wrapper around `LazyBox<imp::RwLock>` or `imp::RwLock`, -/// depending on the platform. It is boxed on platforms where `imp::RwLock` may -/// not be moved. -pub struct MovableRwLock(imp::MovableRwLock); - -impl MovableRwLock { - /// Creates a new reader-writer lock for use. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self(imp::MovableRwLock::new()) - } - - /// Acquires shared access to the underlying lock, blocking the current - /// thread to do so. - #[inline] - pub fn read(&self) { - unsafe { self.0.read() } - } - - /// Attempts to acquire shared access to this lock, returning whether it - /// succeeded or not. - /// - /// This function does not block the current thread. - #[inline] - pub fn try_read(&self) -> bool { - unsafe { self.0.try_read() } - } - - /// Acquires write access to the underlying lock, blocking the current thread - /// to do so. - #[inline] - pub fn write(&self) { - unsafe { self.0.write() } - } - - /// Attempts to acquire exclusive access to this lock, returning whether it - /// succeeded or not. - /// - /// This function does not block the current thread. - #[inline] - pub fn try_write(&self) -> bool { - unsafe { self.0.try_write() } - } - - /// Unlocks previously acquired shared access to this lock. - /// - /// Behavior is undefined if the current thread does not have shared access. - #[inline] - pub unsafe fn read_unlock(&self) { - self.0.read_unlock() - } - - /// Unlocks previously acquired exclusive access to this lock. - /// - /// Behavior is undefined if the current thread does not currently have - /// exclusive access. - #[inline] - pub unsafe fn write_unlock(&self) { - self.0.write_unlock() - } -} |