Kernel: Implement SpinLock without CriticalScope

This actually is not even spinlock since it yields the current
thread. It will become one when I get to SMP though...
This commit is contained in:
Bananymous 2024-01-30 01:07:06 +02:00
parent cc79f55817
commit ca8e7b40bc
2 changed files with 5 additions and 18 deletions

View File

@ -1,5 +1,6 @@
#pragma once #pragma once
#include <BAN/Atomic.h>
#include <BAN/NoCopyMove.h> #include <BAN/NoCopyMove.h>
#include <sys/types.h> #include <sys/types.h>
@ -19,7 +20,7 @@ namespace Kernel
bool is_locked() const; bool is_locked() const;
private: private:
volatile pid_t m_locker = -1; BAN::Atomic<pid_t> m_locker = -1;
}; };
class RecursiveSpinLock class RecursiveSpinLock
@ -34,8 +35,8 @@ namespace Kernel
bool is_locked() const; bool is_locked() const;
private: private:
pid_t m_locker = -1; BAN::Atomic<pid_t> m_locker = -1;
uint32_t m_lock_depth = 0; BAN::Atomic<uint32_t> m_lock_depth = 0;
SpinLock m_lock; SpinLock m_lock;
}; };

View File

@ -1,6 +1,5 @@
#include <kernel/Scheduler.h> #include <kernel/Scheduler.h>
#include <kernel/SpinLock.h> #include <kernel/SpinLock.h>
#include <kernel/CriticalScope.h>
namespace Kernel namespace Kernel
{ {
@ -8,31 +7,18 @@ namespace Kernel
void SpinLock::lock() void SpinLock::lock()
{ {
pid_t tid = Scheduler::current_tid(); pid_t tid = Scheduler::current_tid();
while (true) while (!m_locker.compare_exchange(-1, tid))
{
{
CriticalScope _;
ASSERT(m_locker != tid);
if (m_locker == -1)
{
m_locker = tid;
break;
}
}
Scheduler::get().reschedule(); Scheduler::get().reschedule();
} }
}
void SpinLock::unlock() void SpinLock::unlock()
{ {
CriticalScope _;
ASSERT(m_locker == Scheduler::current_tid()); ASSERT(m_locker == Scheduler::current_tid());
m_locker = -1; m_locker = -1;
} }
bool SpinLock::is_locked() const bool SpinLock::is_locked() const
{ {
CriticalScope _;
return m_locker != -1; return m_locker != -1;
} }