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#ifndef RECURSIVE_SPIN_LOCK_INL_H_
#error "Direct inclusion of this file is not allowed, include recursive_spinlock.h"
// For the sake of sane code completion.
#include "recursive_spin_lock.h"
#endif
#undef RECURSIVE_SPIN_LOCK_INL_H_
#include "spin_wait.h"
#include <library/cpp/yt/assert/assert.h>
namespace NYT::NThreading {
////////////////////////////////////////////////////////////////////////////////
inline void TRecursiveSpinLock::Acquire() noexcept
{
if (TryAcquire()) {
return;
}
AcquireSlow();
}
inline bool TRecursiveSpinLock::TryAcquire() noexcept
{
auto currentThreadId = GetSequentialThreadId();
auto oldValue = Value_.load();
auto oldRecursionDepth = oldValue & RecursionDepthMask;
if (oldRecursionDepth > 0 && (oldValue >> ThreadIdShift) != currentThreadId) {
return false;
}
auto newValue = (oldRecursionDepth + 1) | (static_cast<TValue>(currentThreadId) << ThreadIdShift);
return Value_.compare_exchange_weak(oldValue, newValue);
}
inline void TRecursiveSpinLock::Release() noexcept
{
#ifndef NDEBUG
auto value = Value_.load();
YT_ASSERT((value & RecursionDepthMask) > 0);
YT_ASSERT((value >> ThreadIdShift) == GetSequentialThreadId());
#endif
--Value_;
}
inline bool TRecursiveSpinLock::IsLocked() const noexcept
{
auto value = Value_.load();
return (value & RecursionDepthMask) > 0;
}
inline bool TRecursiveSpinLock::IsLockedByCurrentThread() const noexcept
{
auto value = Value_.load();
return (value & RecursionDepthMask) > 0 && (value >> ThreadIdShift) == GetSequentialThreadId();
}
inline bool TRecursiveSpinLock::TryAndTryAcquire() noexcept
{
auto value = Value_.load(std::memory_order_relaxed);
auto recursionDepth = value & RecursionDepthMask;
if (recursionDepth > 0 && (value >> ThreadIdShift) != GetSequentialThreadId()) {
return false;
}
return TryAcquire();
}
////////////////////////////////////////////////////////////////////////////////
} // namespace NYT::NThreading
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