59 lines
1.0 KiB
C++
59 lines
1.0 KiB
C++
#include <luna/DebugLog.h>
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#include <luna/Spinlock.h>
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#ifdef ARCH_X86_64
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#define pause() asm volatile("pause")
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#else
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#error "Unsupported architecture"
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#endif
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void Spinlock::lock()
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{
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int expected = 0;
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while (!m_lock.compare_exchange_strong(expected, 1))
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{
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expected = 0;
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pause();
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}
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}
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bool Spinlock::try_lock()
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{
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int expected = 0;
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return m_lock.compare_exchange_strong(expected, 1);
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}
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void Spinlock::unlock()
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{
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int expected = 1;
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if (!m_lock.compare_exchange_strong(expected, 0))
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{
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dbgln("Spinlock::unlock() called on an unlocked lock with value %d", expected);
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}
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}
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ScopeLock::ScopeLock(Spinlock& lock) : m_lock(lock)
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{
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m_lock.lock();
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}
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ScopeLock::~ScopeLock()
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{
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if (!m_taken_over) m_lock.unlock();
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}
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const u32 RETRIES = 5000000;
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SafeScopeLock::SafeScopeLock(Spinlock& lock) : m_lock(lock)
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{
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u32 tries_left = RETRIES;
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while (!lock.try_lock() && --tries_left) { pause(); }
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if (tries_left) m_success = true;
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}
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SafeScopeLock::~SafeScopeLock()
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{
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if (m_success) m_lock.unlock();
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}
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