Subject: [Boost-commit] svn:boost r83553 - trunk/boost/thread/pthread
From: vicente.botet_at_[hidden]
Date: 2013-03-24 19:45:34
Author: viboes
Date: 2013-03-24 19:45:33 EDT (Sun, 24 Mar 2013)
New Revision: 83553
URL: http://svn.boost.org/trac/boost/changeset/83553
Log:
Thread: more refactoring on pthread/shared_mutex.hpp.
Text files modified:
trunk/boost/thread/pthread/shared_mutex.hpp | 67 +++++++++++++++++++--------------------
1 files changed, 33 insertions(+), 34 deletions(-)
Modified: trunk/boost/thread/pthread/shared_mutex.hpp
==============================================================================
--- trunk/boost/thread/pthread/shared_mutex.hpp (original)
+++ trunk/boost/thread/pthread/shared_mutex.hpp 2013-03-24 19:45:33 EDT (Sun, 24 Mar 2013)
@@ -28,7 +28,7 @@
{
class shared_mutex
{
- //private:
+ private:
class state_data
{
public:
@@ -100,9 +100,9 @@
return ! (exclusive || exclusive_waiting_blocked);
}
- bool is_last_shared () const
+ bool more_shared () const
{
- return !shared_count ;
+ return shared_count > 0 ;
}
unsigned get_shared_count () const
{
@@ -186,27 +186,23 @@
boost::this_thread::disable_interruption do_not_disturb;
#endif
boost::unique_lock<boost::mutex> lk(state_change);
-
- while(state.exclusive || state.exclusive_waiting_blocked)
+ while(!state.can_lock_shared())
{
shared_cond.wait(lk);
}
- ++state.shared_count;
+ state.lock_shared();
}
bool try_lock_shared()
{
boost::unique_lock<boost::mutex> lk(state_change);
- if(state.exclusive || state.exclusive_waiting_blocked)
+ if(!state.can_lock_shared())
{
return false;
}
- else
- {
- ++state.shared_count;
- return true;
- }
+ state.lock_shared();
+ return true;
}
#if defined BOOST_THREAD_USES_DATETIME
@@ -217,14 +213,14 @@
#endif
boost::unique_lock<boost::mutex> lk(state_change);
- while(state.exclusive || state.exclusive_waiting_blocked)
+ while(!state.can_lock_shared())
{
if(!shared_cond.timed_wait(lk,timeout))
{
return false;
}
}
- ++state.shared_count;
+ state.lock_shared();
return true;
}
@@ -248,14 +244,15 @@
#endif
boost::unique_lock<boost::mutex> lk(state_change);
- while(state.exclusive || state.exclusive_waiting_blocked)
+ while(!state.can_lock_shared())
+ //while(state.exclusive || state.exclusive_waiting_blocked)
{
if(cv_status::timeout==shared_cond.wait_until(lk,abs_time))
{
return false;
}
}
- ++state.shared_count;
+ state.lock_shared();
return true;
}
#endif
@@ -263,19 +260,22 @@
{
boost::unique_lock<boost::mutex> lk(state_change);
state.assert_lock_shared();
- bool const last_reader=!--state.shared_count;
-
- if(last_reader)
+ state.unlock_shared();
+ if (! state.more_shared())
{
- if(state.upgrade)
+ if (state.upgrade)
{
+ // As there is a thread doing a unlock_upgrade_and_lock that is waiting for ! state.more_shared()
+ // avoid other threads to lock, lock_upgrade or lock_shared, so only this thread is notified.
state.upgrade=false;
state.exclusive=true;
+ lk.unlock();
upgrade_cond.notify_one();
}
else
{
state.exclusive_waiting_blocked=false;
+ lk.unlock();
}
release_waiters();
}
@@ -288,7 +288,7 @@
#endif
boost::unique_lock<boost::mutex> lk(state_change);
- while(state.shared_count || state.exclusive)
+ while (state.shared_count || state.exclusive)
{
state.exclusive_waiting_blocked=true;
exclusive_cond.wait(lk);
@@ -397,7 +397,7 @@
{
shared_cond.wait(lk);
}
- ++state.shared_count;
+ state.lock_shared();
state.upgrade=true;
}
@@ -419,7 +419,7 @@
break;
}
}
- ++state.shared_count;
+ state.lock_shared();
state.upgrade=true;
return true;
}
@@ -454,7 +454,7 @@
break;
}
}
- ++state.shared_count;
+ state.lock_shared();
state.upgrade=true;
return true;
}
@@ -468,7 +468,7 @@
}
else
{
- ++state.shared_count;
+ state.lock_shared();
state.upgrade=true;
state.assert_lock_upgraded();
return true;
@@ -478,15 +478,14 @@
void unlock_upgrade()
{
boost::unique_lock<boost::mutex> lk(state_change);
- state.upgrade=false;
- bool const last_reader=!--state.shared_count;
-
- if(last_reader)
+ //state.upgrade=false;
+ state.unlock_upgrade();
+ if(! state.more_shared() )
{
state.exclusive_waiting_blocked=false;
release_waiters();
} else {
- shared_cond.notify_all();
+ shared_cond.notify_all();
}
}
@@ -498,8 +497,8 @@
#endif
boost::unique_lock<boost::mutex> lk(state_change);
state.assert_lock_upgraded();
- --state.shared_count;
- while(state.shared_count)
+ state.unlock_shared();
+ while (state.more_shared())
{
upgrade_cond.wait(lk);
}
@@ -514,7 +513,7 @@
state.assert_locked();
state.exclusive=false;
state.upgrade=true;
- ++state.shared_count;
+ state.lock_shared();
state.exclusive_waiting_blocked=false;
state.assert_lock_upgraded();
release_waiters();
@@ -581,7 +580,7 @@
boost::unique_lock<boost::mutex> lk(state_change);
state.assert_locked();
state.exclusive=false;
- ++state.shared_count;
+ state.lock_shared();
state.exclusive_waiting_blocked=false;
release_waiters();
}