libcruft-util/thread/ticketlock.cpp
Danny Robson f6056153e3 rename root namespace from util to cruft
This places, at long last, the core library code into the same namespace
as the extended library code.
2018-08-05 14:42:02 +10:00

38 lines
805 B
C++

/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright 2018 Danny Robson <danny@nerdcruft.net>
*/
#include "ticketlock.hpp"
using cruft::thread::ticketlock;
///////////////////////////////////////////////////////////////////////////////
ticketlock::ticketlock ():
current (0),
next (0)
{ }
///////////////////////////////////////////////////////////////////////////////
void
ticketlock::lock (void)
{
auto self = next++;
while (current != self)
__asm__ volatile ("pause");
}
//-----------------------------------------------------------------------------
void
ticketlock::unlock (void)
{
++current;
}