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9abcb6700c
The code in Spinlock.h has no architectural specific logic, thus can be moved to the Arch directory. This contains no functional change. Also add the Spinlock.cpp file for aarch64 which contains stubs for the lock and unlock functions.
71 lines
1.6 KiB
C++
71 lines
1.6 KiB
C++
/*
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* Copyright (c) 2020-2022, Andreas Kling <kling@serenityos.org>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#include <Kernel/Arch/Spinlock.h>
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namespace Kernel {
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u32 Spinlock::lock()
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{
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u32 prev_flags = cpu_flags();
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Processor::enter_critical();
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cli();
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while (m_lock.exchange(1, AK::memory_order_acquire) != 0)
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Processor::wait_check();
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track_lock_acquire(m_rank);
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return prev_flags;
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}
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void Spinlock::unlock(u32 prev_flags)
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{
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VERIFY(is_locked());
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track_lock_release(m_rank);
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m_lock.store(0, AK::memory_order_release);
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if ((prev_flags & 0x200) != 0)
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sti();
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else
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cli();
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Processor::leave_critical();
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}
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u32 RecursiveSpinlock::lock()
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{
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u32 prev_flags = cpu_flags();
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cli();
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Processor::enter_critical();
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auto& proc = Processor::current();
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FlatPtr cpu = FlatPtr(&proc);
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FlatPtr expected = 0;
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while (!m_lock.compare_exchange_strong(expected, cpu, AK::memory_order_acq_rel)) {
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if (expected == cpu)
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break;
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Processor::wait_check();
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expected = 0;
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}
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if (m_recursions == 0)
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track_lock_acquire(m_rank);
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m_recursions++;
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return prev_flags;
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}
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void RecursiveSpinlock::unlock(u32 prev_flags)
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{
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VERIFY(m_recursions > 0);
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VERIFY(m_lock.load(AK::memory_order_relaxed) == FlatPtr(&Processor::current()));
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if (--m_recursions == 0) {
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track_lock_release(m_rank);
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m_lock.store(0, AK::memory_order_release);
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}
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if ((prev_flags & 0x200) != 0)
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sti();
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else
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cli();
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Processor::leave_critical();
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}
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}
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