-//$$CDS-header$$
+/*
+ This file is a part of libcds - Concurrent Data Structures library
+
+ (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2017
+
+ Source code repo: http://github.com/khizmax/libcds/
+ Download: http://sourceforge.net/projects/libcds/files/
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
#ifndef CDSLIB_SYNC_MONITOR_H
#define CDSLIB_SYNC_MONITOR_H
#include <cds/details/defs.h>
namespace cds { namespace sync {
-
/**
@page cds_sync_monitor Synchronization monitor
-
- A <a href="http://en.wikipedia.org/wiki/Monitor_%28synchronization%29">monitor</a> is synchronization construct
+ A <a href="http://en.wikipedia.org/wiki/Monitor_%28synchronization%29">monitor</a> is synchronization construction
that allows threads to have both mutual exclusion and the ability to wait (block) for a certain condition to become true.
-
Some blocking data structure algoritms like the trees require per-node locking.
For huge trees containing millions of nodes it can be very inefficient to inject
the lock object into each node. Moreover, some operating systems may not support
- \p sync::injecting_monitor injects the lock object into each node.
That mock monitor is designed for user-space locking primitive like
\ref sync::spin_lock "spin-lock".
- - \p sync::pool_monitor is the monitor that allocates the lock object
- for the node from the pool when needed. When the node is unlocked
+ - \p sync::pool_monitor is the monitor that allocates a lock object
+ for a node from the pool when needed. When the node is unlocked
the lock assigned to it is given back to the pool if no thread
references to that node.
<b>How to use</b>
If you use a container from \p libcds that requires a monitor, you should just
- specify required monitor type in container's traits. Usually, the monitor
+ specify required monitor type in container's traits. Usually, the monitor
is specified by \p traits::sync_monitor typedef, or by \p cds::opt::sync_monitor
option for container's \p make_traits metafunction.
- If you're developing a new container algorithm, you should know internal monitor
+ If you're developing a new container algorithm, you should know internal monitor
interface:
\code
class Monitor {
template <typename Node>
struct node_injection: public Node
{
- // Monitor data to inject into container's node
- // ...
+ // Monitor data injecting into container's node
+ // ...
};
-
- // Locks the node
+ // Locks the node
template <typename Node>
void lock( Node& node );
-
// Unlocks the node
template <typename Node>
void unlock( Node& node );
-
// Scoped lock applyes RAII to Monitor
template <typename Node>
using scoped_lock = monitor_scoped_lock< pool_monitor, Node >;
};
\endcode
-
- Monitor's data must be inject into container's node as \p m_SyncMonitorInjection data member:
+ Monitor's data must be injected into container's node as \p m_SyncMonitorInjection data member:
\code
template <typename SyncMonitor>
struct my_node
typename SyncMonitor::node_injection m_SyncMonitorInjection;
};
\endcode
-
The monitor must be a member of your container:
\code
template <typename GC, typename T, typename Traits>
};
\endcode
*/
-
/// Monitor scoped lock (RAII)
/**
Template arguments:
public:
typedef Monitor monitor_type; ///< Monitor type
typedef Node node_type; ///< Node type
-
private:
//@cond
monitor_type& m_Monitor; ///< Monitor
node_type const& m_Node; ///< Our locked node
//@endcond
-
public:
/// Makes exclusive access to the node \p p by \p monitor
monitor_scoped_lock( monitor_type& monitor, node_type const& p )
{
monitor.lock( p );
}
-
/// Unlocks the node
~monitor_scoped_lock()
{
m_Monitor.unlock( m_Node );
}
};
-
}} // namespace cds::sync
-
#endif // #ifndef CDSLIB_SYNC_MONITOR_H