From 875dc41cd5791dbea3fccfbdb9ee926b47aa4f2b Mon Sep 17 00:00:00 2001
From: Taiki Endo <te316e89@gmail.com>
Date: Thu, 24 Dec 2020 21:22:11 +0900
Subject: [PATCH] Replace deprecated compare_and_swap with compare_exchange

---
 src/mutex.rs  | 30 +++++++++++++++++++++++++-----
 src/rwlock.rs | 10 +++++++---
 2 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/mutex.rs b/src/mutex.rs
index 8d079e1..d86cb6d 100644
--- a/src/mutex.rs
+++ b/src/mutex.rs
@@ -117,7 +117,11 @@ impl<T: ?Sized> Mutex<T> {
             let listener = self.lock_ops.listen();
 
             // Try locking if nobody is being starved.
-            match self.state.compare_and_swap(0, 1, Ordering::Acquire) {
+            match self
+                .state
+                .compare_exchange(0, 1, Ordering::Acquire, Ordering::Acquire)
+                .unwrap_or_else(|x| x)
+            {
                 // Lock acquired!
                 0 => return,
 
@@ -132,7 +136,11 @@ impl<T: ?Sized> Mutex<T> {
             listener.await;
 
             // Try locking if nobody is being starved.
-            match self.state.compare_and_swap(0, 1, Ordering::Acquire) {
+            match self
+                .state
+                .compare_exchange(0, 1, Ordering::Acquire, Ordering::Acquire)
+                .unwrap_or_else(|x| x)
+            {
                 // Lock acquired!
                 0 => return,
 
@@ -171,7 +179,11 @@ impl<T: ?Sized> Mutex<T> {
             let listener = self.lock_ops.listen();
 
             // Try locking if nobody else is being starved.
-            match self.state.compare_and_swap(2, 2 | 1, Ordering::Acquire) {
+            match self
+                .state
+                .compare_exchange(2, 2 | 1, Ordering::Acquire, Ordering::Acquire)
+                .unwrap_or_else(|x| x)
+            {
                 // Lock acquired!
                 2 => return,
 
@@ -213,7 +225,11 @@ impl<T: ?Sized> Mutex<T> {
     /// ```
     #[inline]
     pub fn try_lock(&self) -> Option<MutexGuard<'_, T>> {
-        if self.state.compare_and_swap(0, 1, Ordering::Acquire) == 0 {
+        if self
+            .state
+            .compare_exchange(0, 1, Ordering::Acquire, Ordering::Acquire)
+            .is_ok()
+        {
             Some(MutexGuard(self))
         } else {
             None
@@ -286,7 +302,11 @@ impl<T: ?Sized> Mutex<T> {
     /// ```
     #[inline]
     pub fn try_lock_arc(self: &Arc<Self>) -> Option<MutexGuardArc<T>> {
-        if self.state.compare_and_swap(0, 1, Ordering::Acquire) == 0 {
+        if self
+            .state
+            .compare_exchange(0, 1, Ordering::Acquire, Ordering::Acquire)
+            .is_ok()
+        {
             Some(MutexGuardArc(self.clone()))
         } else {
             None
diff --git a/src/rwlock.rs b/src/rwlock.rs
index 4354f28..f3a9c79 100644
--- a/src/rwlock.rs
+++ b/src/rwlock.rs
@@ -342,7 +342,11 @@ impl<T: ?Sized> RwLock<T> {
         let lock = self.mutex.try_lock()?;
 
         // If there are no readers, grab the write lock.
-        if self.state.compare_and_swap(0, WRITER_BIT, Ordering::AcqRel) == 0 {
+        if self
+            .state
+            .compare_exchange(0, WRITER_BIT, Ordering::AcqRel, Ordering::Acquire)
+            .is_ok()
+        {
             Some(RwLockWriteGuard {
                 writer: RwLockWriteGuardInner(self),
                 reserved: lock,
@@ -555,8 +559,8 @@ impl<'a, T: ?Sized> RwLockUpgradableReadGuard<'a, T> {
             .reader
             .0
             .state
-            .compare_and_swap(ONE_READER, WRITER_BIT, Ordering::AcqRel)
-            == ONE_READER
+            .compare_exchange(ONE_READER, WRITER_BIT, Ordering::AcqRel, Ordering::Acquire)
+            .is_ok()
         {
             Ok(guard.into_writer())
         } else {