From 061b56bd5ca2d3a49bebdd6a174995e1b3ec6a5b Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 13:47:39 +0200 Subject: [PATCH 1/8] Add a link to `park` in the `park_timeout` doc. Part of #29378 --- src/libstd/thread/mod.rs | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 8e7eaa77cd709..dbc8562ea39fd 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -585,9 +585,9 @@ pub fn park() { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to `park()` except that the -/// thread will be blocked for roughly no longer than `ms`. This method -/// should not be used for precise timing due to anomalies such as +/// The semantics of this function are equivalent to [`park()`][[park] except +/// that the thread will be blocked for roughly no longer than `dur`. This +/// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `ms` long. /// @@ -595,6 +595,7 @@ pub fn park() { /// /// [thread]: index.html /// [park_timeout]: fn.park_timeout.html +/// [park]: fn.park.html #[stable(feature = "rust1", since = "1.0.0")] #[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::thread::park_timeout`")] pub fn park_timeout_ms(ms: u32) { @@ -604,9 +605,9 @@ pub fn park_timeout_ms(ms: u32) { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to `park()` except that the -/// thread will be blocked for roughly no longer than `dur`. This method -/// should not be used for precise timing due to anomalies such as +/// The semantics of this function are equivalent to [`park()`][[park] except +/// that the thread will be blocked for roughly no longer than `dur`. This +/// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `dur` long. /// @@ -635,6 +636,8 @@ pub fn park_timeout_ms(ms: u32) { /// park_timeout(timeout); /// } /// ``` +/// +/// [park]: fn.park.html #[stable(feature = "park_timeout", since = "1.4.0")] pub fn park_timeout(dur: Duration) { let thread = current(); From c158962169e3cf0686cb70652282bcdf20772926 Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 13:50:23 +0200 Subject: [PATCH 2/8] Add link to the module doc in `park_timeout`. Part of #29378 --- src/libstd/thread/mod.rs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index dbc8562ea39fd..1857f81a33967 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -611,7 +611,7 @@ pub fn park_timeout_ms(ms: u32) { /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `dur` long. /// -/// See the module doc for more detail. +/// See the [module doc][thread] for more detail. /// /// # Platform behavior /// @@ -637,6 +637,7 @@ pub fn park_timeout_ms(ms: u32) { /// } /// ``` /// +/// [thread]: index.html /// [park]: fn.park.html #[stable(feature = "park_timeout", since = "1.4.0")] pub fn park_timeout(dur: Duration) { From d9628f9389319c1075d4a54a0a490226539cea81 Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 13:54:06 +0200 Subject: [PATCH 3/8] Add `park` info to `unpark`. - Adds an explanantion of what `park` does in the `unpark` documentation. - Adds a link to the module doc. --- src/libstd/thread/mod.rs | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 1857f81a33967..bdf7b1134bfe7 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -768,7 +768,11 @@ impl Thread { /// Atomically makes the handle's token available if it is not already. /// - /// See the module doc for more detail. + /// Every thread is equipped with some basic low-level blocking support, via + /// the [`park()`][park] function and the `unpark` method. These can be + /// used as a more CPU-efficient implementation of a spinlock. + /// + /// See the [module doc][thread] for more detail. /// /// # Examples /// @@ -784,6 +788,9 @@ impl Thread { /// /// handler.join().unwrap(); /// ``` + /// + /// [thread]: index.html + /// [park]: fn.park.html #[stable(feature = "rust1", since = "1.0.0")] pub fn unpark(&self) { let mut guard = self.inner.lock.lock().unwrap(); From 5573c4709cba7b3d5dc15c47239d1b1f32af4753 Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 16:01:47 +0200 Subject: [PATCH 4/8] Better example for `thread::unpark`. Part of #29378 --- src/libstd/thread/mod.rs | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index bdf7b1134bfe7..94a2c91858ea7 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -769,7 +769,7 @@ impl Thread { /// Atomically makes the handle's token available if it is not already. /// /// Every thread is equipped with some basic low-level blocking support, via - /// the [`park()`][park] function and the `unpark` method. These can be + /// the [`park()`][park] function and the `unpark()` method. These can be /// used as a more CPU-efficient implementation of a spinlock. /// /// See the [module doc][thread] for more detail. @@ -779,14 +779,21 @@ impl Thread { /// ``` /// use std::thread; /// - /// let handler = thread::Builder::new() + /// let parked_thread = thread::Builder::new() /// .spawn(|| { - /// let thread = thread::current(); - /// thread.unpark(); + /// println!("Parking thread"); + /// thread::park(); + /// println!("Thread unparked"); /// }) /// .unwrap(); /// - /// handler.join().unwrap(); + /// // Let some time pass for the thread to be spawned. + /// thread::sleep(Duration::from_millis(10)); + /// + /// println!("Unpark the thread"); + /// parked_thread.thread().unpark(); + /// + /// parked_thread.join().unwrap(); /// ``` /// /// [thread]: index.html From c0d475ad7b44c153b4999709ff08a9275160ea1c Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 16:22:13 +0200 Subject: [PATCH 5/8] fix typo --- src/libstd/thread/mod.rs | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 94a2c91858ea7..9c15857edf693 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -585,7 +585,7 @@ pub fn park() { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to [`park()`][[park] except +/// The semantics of this function are equivalent to [`park()`][park] except /// that the thread will be blocked for roughly no longer than `dur`. This /// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum @@ -605,7 +605,7 @@ pub fn park_timeout_ms(ms: u32) { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to [`park()`][[park] except +/// The semantics of this function are equivalent to [`park()`][park] except /// that the thread will be blocked for roughly no longer than `dur`. This /// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum From fa0cdaa63f575c81c7cc87239f7dfcc677362c78 Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 18:55:20 +0200 Subject: [PATCH 6/8] Inline `thread::park` documentation. Part of #29378 - Moves the module documentation into `park`. - Add the same example as the one from `unpark` to `park`. --- src/libstd/thread/mod.rs | 114 +++++++++++++++++++++------------------ 1 file changed, 62 insertions(+), 52 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 9c15857edf693..5373bf273d4de 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -96,41 +96,6 @@ //! The [`thread::current`] function is available even for threads not spawned //! by the APIs of this module. //! -//! ## Blocking support: park and unpark -//! -//! Every thread is equipped with some basic low-level blocking support, via the -//! [`thread::park`][`park`] function and [`thread::Thread::unpark()`][`unpark`] -//! method. [`park`] blocks the current thread, which can then be resumed from -//! another thread by calling the [`unpark`] method on the blocked thread's handle. -//! -//! Conceptually, each [`Thread`] handle has an associated token, which is -//! initially not present: -//! -//! * The [`thread::park`][`park`] function blocks the current thread unless or until -//! the token is available for its thread handle, at which point it atomically -//! consumes the token. It may also return *spuriously*, without consuming the -//! token. [`thread::park_timeout`] does the same, but allows specifying a -//! maximum time to block the thread for. -//! -//! * The [`unpark`] method on a [`Thread`] atomically makes the token available -//! if it wasn't already. -//! -//! In other words, each [`Thread`] acts a bit like a semaphore with initial count -//! 0, except that the semaphore is *saturating* (the count cannot go above 1), -//! and can return spuriously. -//! -//! The API is typically used by acquiring a handle to the current thread, -//! placing that handle in a shared data structure so that other threads can -//! find it, and then `park`ing. When some desired condition is met, another -//! thread calls [`unpark`] on the handle. -//! -//! The motivation for this design is twofold: -//! -//! * It avoids the need to allocate mutexes and condvars when building new -//! synchronization primitives; the threads already provide basic blocking/signaling. -//! -//! * It can be implemented very efficiently on many platforms. -//! //! ## Thread-local storage //! //! This module also provides an implementation of thread-local storage for Rust @@ -547,23 +512,71 @@ pub fn sleep(dur: Duration) { /// Blocks unless or until the current thread's token is made available. /// -/// Every thread is equipped with some basic low-level blocking support, via -/// the `park()` function and the [`unpark`][unpark] method. These can be -/// used as a more CPU-efficient implementation of a spinlock. +/// A call to `park` does not guarantee that the thread will remain parked +/// forever, and callers should be prepared for this possibility. +/// +/// # park and unpark +/// +/// Every thread is equipped with some basic low-level blocking support, via the +/// [`thread::park`][`park`] function and [`thread::Thread::unpark()`][`unpark`] +/// method. [`park`] blocks the current thread, which can then be resumed from +/// another thread by calling the [`unpark`] method on the blocked thread's +/// handle. +/// +/// Conceptually, each [`Thread`] handle has an associated token, which is +/// initially not present: +/// +/// * The [`thread::park`][`park`] function blocks the current thread unless or +/// until the token is available for its thread handle, at which point it +/// atomically consumes the token. It may also return *spuriously*, without +/// consuming the token. [`thread::park_timeout`] does the same, but allows +/// specifying a maximum time to block the thread for. +/// +/// * The [`unpark`] method on a [`Thread`] atomically makes the token available +/// if it wasn't already. /// -/// [unpark]: struct.Thread.html#method.unpark +/// In other words, each [`Thread`] acts a bit like a spinlock that can be +/// locked and unlocked using `park` and `unpark`. /// /// The API is typically used by acquiring a handle to the current thread, /// placing that handle in a shared data structure so that other threads can -/// find it, and then parking (in a loop with a check for the token actually -/// being acquired). +/// find it, and then `park`ing. When some desired condition is met, another +/// thread calls [`unpark`] on the handle. /// -/// A call to `park` does not guarantee that the thread will remain parked -/// forever, and callers should be prepared for this possibility. +/// The motivation for this design is twofold: +/// +/// * It avoids the need to allocate mutexes and condvars when building new +/// synchronization primitives; the threads already provide basic +/// blocking/signaling. /// -/// See the [module documentation][thread] for more detail. +/// * It can be implemented very efficiently on many platforms. +/// +/// # Examples /// -/// [thread]: index.html +/// ``` +/// use std::thread; +/// +/// let parked_thread = thread::Builder::new() +/// .spawn(|| { +/// println!("Parking thread"); +/// thread::park(); +/// println!("Thread unparked"); +/// }) +/// .unwrap(); +/// +/// // Let some time pass for the thread to be spawned. +/// thread::sleep(Duration::from_millis(10)); +/// +/// println!("Unpark the thread"); +/// parked_thread.thread().unpark(); +/// +/// parked_thread.join().unwrap(); +/// ``` +/// +/// [`Thread`]: ../../std/thread/struct.Thread.html +/// [`park`]: ../../std/thread/fn.park.html +/// [`unpark`]: ../../std/thread/struct.Thread.html#method.unpark +/// [`thread::park_timeout`]: ../../std/thread/fn.park_timeout.html // // The implementation currently uses the trivial strategy of a Mutex+Condvar // with wakeup flag, which does not actually allow spurious wakeups. In the @@ -591,11 +604,10 @@ pub fn park() { /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `ms` long. /// -/// See the [module documentation][thread] for more detail. +/// See the [park documentation][park] for more detail. /// -/// [thread]: index.html /// [park_timeout]: fn.park_timeout.html -/// [park]: fn.park.html +/// [park]: ../../std/thread/fn.park.html #[stable(feature = "rust1", since = "1.0.0")] #[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::thread::park_timeout`")] pub fn park_timeout_ms(ms: u32) { @@ -611,7 +623,7 @@ pub fn park_timeout_ms(ms: u32) { /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `dur` long. /// -/// See the [module doc][thread] for more detail. +/// See the [park dococumentation][park] for more details. /// /// # Platform behavior /// @@ -637,7 +649,6 @@ pub fn park_timeout_ms(ms: u32) { /// } /// ``` /// -/// [thread]: index.html /// [park]: fn.park.html #[stable(feature = "park_timeout", since = "1.4.0")] pub fn park_timeout(dur: Duration) { @@ -772,7 +783,7 @@ impl Thread { /// the [`park()`][park] function and the `unpark()` method. These can be /// used as a more CPU-efficient implementation of a spinlock. /// - /// See the [module doc][thread] for more detail. + /// See the [park documentation][park] for more details. /// /// # Examples /// @@ -796,7 +807,6 @@ impl Thread { /// parked_thread.join().unwrap(); /// ``` /// - /// [thread]: index.html /// [park]: fn.park.html #[stable(feature = "rust1", since = "1.0.0")] pub fn unpark(&self) { From 03c9510525c986715af1f1f98c2bc06248c747e8 Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Sun, 7 May 2017 21:43:46 +0200 Subject: [PATCH 7/8] Fix typos in `thread::park` documentation. --- src/libstd/thread/mod.rs | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 5373bf273d4de..4d931682676e1 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -518,7 +518,7 @@ pub fn sleep(dur: Duration) { /// # park and unpark /// /// Every thread is equipped with some basic low-level blocking support, via the -/// [`thread::park`][`park`] function and [`thread::Thread::unpark()`][`unpark`] +/// [`thread::park`][`park`] function and [`thread::Thread::unpark`][`unpark`] /// method. [`park`] blocks the current thread, which can then be resumed from /// another thread by calling the [`unpark`] method on the blocked thread's /// handle. @@ -555,6 +555,7 @@ pub fn sleep(dur: Duration) { /// /// ``` /// use std::thread; +/// use std::time::Duration; /// /// let parked_thread = thread::Builder::new() /// .spawn(|| { @@ -598,7 +599,7 @@ pub fn park() { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to [`park()`][park] except +/// The semantics of this function are equivalent to [`park`][park] except /// that the thread will be blocked for roughly no longer than `dur`. This /// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum @@ -617,7 +618,7 @@ pub fn park_timeout_ms(ms: u32) { /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to [`park()`][park] except +/// The semantics of this function are equivalent to [`park`][park] except /// that the thread will be blocked for roughly no longer than `dur`. This /// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum @@ -780,7 +781,7 @@ impl Thread { /// Atomically makes the handle's token available if it is not already. /// /// Every thread is equipped with some basic low-level blocking support, via - /// the [`park()`][park] function and the `unpark()` method. These can be + /// the [`park`][park] function and the `unpark()` method. These can be /// used as a more CPU-efficient implementation of a spinlock. /// /// See the [park documentation][park] for more details. @@ -789,6 +790,7 @@ impl Thread { /// /// ``` /// use std::thread; + /// use std::time::Duration; /// /// let parked_thread = thread::Builder::new() /// .spawn(|| { From afe74c3900aa00373a0d5edd2bd433870822c40a Mon Sep 17 00:00:00 2001 From: Felix Raimundo Date: Tue, 9 May 2017 19:02:43 +0200 Subject: [PATCH 8/8] Fix link --- src/libstd/thread/mod.rs | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 4d931682676e1..9a7239d297c4d 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -594,21 +594,21 @@ pub fn park() { *guard = false; } -/// Use [park_timeout]. +/// Use [`park_timeout`]. /// /// Blocks unless or until the current thread's token is made available or /// the specified duration has been reached (may wake spuriously). /// -/// The semantics of this function are equivalent to [`park`][park] except +/// The semantics of this function are equivalent to [`park`] except /// that the thread will be blocked for roughly no longer than `dur`. This /// method should not be used for precise timing due to anomalies such as /// preemption or platform differences that may not cause the maximum /// amount of time waited to be precisely `ms` long. /// -/// See the [park documentation][park] for more detail. +/// See the [park documentation][`park`] for more detail. /// -/// [park_timeout]: fn.park_timeout.html -/// [park]: ../../std/thread/fn.park.html +/// [`park_timeout`]: fn.park_timeout.html +/// [`park`]: ../../std/thread/fn.park.html #[stable(feature = "rust1", since = "1.0.0")] #[rustc_deprecated(since = "1.6.0", reason = "replaced by `std::thread::park_timeout`")] pub fn park_timeout_ms(ms: u32) {