1
1
Fork 0
forked from suyu/suyu

kernel: convert KAbstractSchedulerLock

This commit is contained in:
Liam 2023-03-06 22:31:50 -05:00
parent 467adc1acd
commit 7322c99e5f

View file

@ -14,74 +14,67 @@
namespace Kernel {
class KernelCore;
class GlobalSchedulerContext;
template <typename SchedulerType>
class KAbstractSchedulerLock {
public:
explicit KAbstractSchedulerLock(KernelCore& kernel_) : kernel{kernel_} {}
explicit KAbstractSchedulerLock(KernelCore& kernel) : m_kernel{kernel} {}
bool IsLockedByCurrentThread() const {
return owner_thread == GetCurrentThreadPointer(kernel);
return m_owner_thread == GetCurrentThreadPointer(m_kernel);
}
void Lock() {
// If we are shutting down the kernel, none of this is relevant anymore.
if (kernel.IsShuttingDown()) {
return;
}
if (IsLockedByCurrentThread()) {
if (this->IsLockedByCurrentThread()) {
// If we already own the lock, the lock count should be > 0.
// For debug, ensure this is true.
ASSERT(lock_count > 0);
ASSERT(m_lock_count > 0);
} else {
// Otherwise, we want to disable scheduling and acquire the spinlock.
SchedulerType::DisableScheduling(kernel);
spin_lock.Lock();
SchedulerType::DisableScheduling(m_kernel);
m_spin_lock.Lock();
ASSERT(lock_count == 0);
ASSERT(owner_thread == nullptr);
ASSERT(m_lock_count == 0);
ASSERT(m_owner_thread == nullptr);
// Take ownership of the lock.
owner_thread = GetCurrentThreadPointer(kernel);
m_owner_thread = GetCurrentThreadPointer(m_kernel);
}
// Increment the lock count.
lock_count++;
m_lock_count++;
}
void Unlock() {
// If we are shutting down the kernel, none of this is relevant anymore.
if (kernel.IsShuttingDown()) {
return;
}
ASSERT(IsLockedByCurrentThread());
ASSERT(lock_count > 0);
ASSERT(this->IsLockedByCurrentThread());
ASSERT(m_lock_count > 0);
// Release an instance of the lock.
if ((--lock_count) == 0) {
if ((--m_lock_count) == 0) {
// Perform a memory barrier here.
std::atomic_thread_fence(std::memory_order_seq_cst);
// We're no longer going to hold the lock. Take note of what cores need scheduling.
const u64 cores_needing_scheduling =
SchedulerType::UpdateHighestPriorityThreads(kernel);
SchedulerType::UpdateHighestPriorityThreads(m_kernel);
// Note that we no longer hold the lock, and unlock the spinlock.
owner_thread = nullptr;
spin_lock.Unlock();
m_owner_thread = nullptr;
m_spin_lock.Unlock();
// Enable scheduling, and perform a rescheduling operation.
SchedulerType::EnableScheduling(kernel, cores_needing_scheduling);
SchedulerType::EnableScheduling(m_kernel, cores_needing_scheduling);
}
}
private:
KernelCore& kernel;
KAlignedSpinLock spin_lock{};
s32 lock_count{};
std::atomic<KThread*> owner_thread{};
friend class GlobalSchedulerContext;
KernelCore& m_kernel;
KAlignedSpinLock m_spin_lock{};
s32 m_lock_count{};
std::atomic<KThread*> m_owner_thread{};
};
} // namespace Kernel