Changeset 44651 in webkit for trunk/JavaScriptCore

Timestamp:

Jun 13, 2009, 10:52:44 AM (16 years ago)

Author:

[email protected]

Message:

2009-06-12 Dave Hyatt <​[email protected]>

Reviewed by Anders Carlsson.

​https://bugs.webkit.org/show_bug.cgi?id=26373

Add a new class to Threading in wtf called ReadWriteLock that handles single writer/multiple reader locking.
Provide a pthreads-only implementation of the lock for now, as this class is only going to be used
on Snow Leopard at first.

• wtf/Threading.h: (WTF::ReadWriteLock::impl):
• wtf/ThreadingPthreads.cpp: (WTF::ReadWriteLock::ReadWriteLock): (WTF::ReadWriteLock::~ReadWriteLock): (WTF::ReadWriteLock::readLock): (WTF::ReadWriteLock::tryReadLock): (WTF::ReadWriteLock::writeLock): (WTF::ReadWriteLock::tryWriteLock): (WTF::ReadWriteLock::unlock):

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• wtf/Threading.h (modified) (4 diffs)
• wtf/ThreadingPthreads.cpp (modified) (1 diff)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2009-06-12  Dave Hyatt  <[email protected]>
+
+        Reviewed by Anders Carlsson.
+
+        https://bugs.webkit.org/show_bug.cgi?id=26373
+
+        Add a new class to Threading in wtf called ReadWriteLock that handles single writer/multiple reader locking.
+        Provide a pthreads-only implementation of the lock for now, as this class is only going to be used
+        on Snow Leopard at first.
+
+        * wtf/Threading.h:
+        (WTF::ReadWriteLock::impl):
+        * wtf/ThreadingPthreads.cpp:
+        (WTF::ReadWriteLock::ReadWriteLock):
+        (WTF::ReadWriteLock::~ReadWriteLock):
+        (WTF::ReadWriteLock::readLock):
+        (WTF::ReadWriteLock::tryReadLock):
+        (WTF::ReadWriteLock::writeLock):
+        (WTF::ReadWriteLock::tryWriteLock):
+        (WTF::ReadWriteLock::unlock):
+
 2009-06-12  Oliver Hunt  <[email protected]>
 

trunk/JavaScriptCore/wtf/Threading.h

@@ -127 +127 @@
 #if USE(PTHREADS)
 typedef pthread_mutex_t PlatformMutex;
+typedef pthread_rwlock_t PlatformReadWriteLock;
 typedef pthread_cond_t PlatformCondition;
 #elif PLATFORM(GTK)
 typedef GOwnPtr<GMutex> PlatformMutex;
+typedef void* PlatformReadWriteLock; // FIXME: Implement.
 typedef GOwnPtr<GCond> PlatformCondition;
 #elif PLATFORM(QT)
 typedef QT_PREPEND_NAMESPACE(QMutex)* PlatformMutex;
+typedef void* PlatformReadWriteLock; // FIXME: Implement.
 typedef QT_PREPEND_NAMESPACE(QWaitCondition)* PlatformCondition;
 #elif PLATFORM(WIN_OS)
@@ -139 +142 @@
     size_t m_recursionCount;
 };
+typedef void* PlatformReadWriteLock; // FIXME: Implement.
 struct PlatformCondition {
     size_t m_waitersGone;
@@ -152 +156 @@
 #else
 typedef void* PlatformMutex;
+typedef void* PlatformReadWriteLock;
 typedef void* PlatformCondition;
 #endif
@@ -171 +176 @@
 
 typedef Locker<Mutex> MutexLocker;
+
+class ReadWriteLock : Noncopyable {
+public:
+    ReadWriteLock();
+    ~ReadWriteLock();
+
+    void readLock();
+    bool tryReadLock();
+
+    void writeLock();
+    bool tryWriteLock();
+    
+    void unlock();
+
+private:
+    PlatformReadWriteLock m_readWriteLock;
+};
 
 class ThreadCondition : Noncopyable {

trunk/JavaScriptCore/wtf/ThreadingPthreads.cpp

@@ -268 +268 @@
 }
 
+
+ReadWriteLock::ReadWriteLock()
+{
+    pthread_rwlock_init(&m_readWriteLock, NULL);
+}
+
+ReadWriteLock::~ReadWriteLock()
+{
+    pthread_rwlock_destroy(&m_readWriteLock);
+}
+
+void ReadWriteLock::readLock()
+{
+    int result = pthread_rwlock_rdlock(&m_readWriteLock);
+    ASSERT_UNUSED(result, !result);
+}
+
+bool ReadWriteLock::tryReadLock()
+{
+    int result = pthread_rwlock_tryrdlock(&m_readWriteLock);
+
+    if (result == 0)
+        return true;
+    if (result == EBUSY || result == EAGAIN)
+        return false;
+
+    ASSERT_NOT_REACHED();
+    return false;
+}
+
+void ReadWriteLock::writeLock()
+{
+    int result = pthread_rwlock_wrlock(&m_readWriteLock);
+    ASSERT_UNUSED(result, !result);
+}
+
+bool ReadWriteLock::tryWriteLock()
+{
+    int result = pthread_rwlock_trywrlock(&m_readWriteLock);
+
+    if (result == 0)
+        return true;
+    if (result == EBUSY || result == EAGAIN)
+        return false;
+
+    ASSERT_NOT_REACHED();
+    return false;
+}
+
+void ReadWriteLock::unlock()
+{
+    int result = pthread_rwlock_unlock(&m_readWriteLock);
+    ASSERT_UNUSED(result, !result);
+}
+
 ThreadCondition::ThreadCondition()
 {