67ba7b89a7
* Introduce Hw namespace and library files under src/lib/hw * Introduce Bootstrap namespace * Move all initialization logic into Bootstrap namespace Ref #2388
50 lines
923 B
C++
50 lines
923 B
C++
/*
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* \brief Spin lock used to synchronize different CPU cores
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* \author Martin Stein
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* \author Stefan Kalkowski
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* \date 2012-11-30
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*/
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/*
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* Copyright (C) 2012-2017 Genode Labs GmbH
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*
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* This file is part of the Genode OS framework, which is distributed
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* under the terms of the GNU Affero General Public License version 3.
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*/
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#ifndef _SRC__LIB__HW__SPIN_LOCK_H_
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#define _SRC__LIB__HW__SPIN_LOCK_H_
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#include <base/lock_guard.h>
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#include <cpu/atomic.h>
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#include <cpu/memory_barrier.h>
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namespace Hw { class Spin_lock; }
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class Hw::Spin_lock
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{
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private:
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enum State { UNLOCKED, LOCKED };
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State volatile _locked = UNLOCKED;
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public:
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void lock()
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{
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while (!Genode::cmpxchg((volatile int*)&_locked, UNLOCKED, LOCKED))
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;
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}
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void unlock()
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{
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Genode::memory_barrier();
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_locked = UNLOCKED;
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}
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using Guard = Genode::Lock_guard<Spin_lock>;
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};
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#endif /* _SRC__LIB__HW__SPIN_LOCK_H_ */
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