serenity/Kernel/TimerQueue.h
Andreas Kling 11eee67b85 Kernel: Make self-contained locking smart pointers their own classes
Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:

- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable

This patch renames the Kernel classes so that they can coexist with
the original AK classes:

- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable

The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.
2022-08-20 17:20:43 +02:00

126 lines
3.3 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/AtomicRefCounted.h>
#include <AK/Function.h>
#include <AK/IntrusiveList.h>
#include <AK/OwnPtr.h>
#include <AK/Time.h>
#include <Kernel/Library/NonnullLockRefPtr.h>
#include <Kernel/Time/TimeManagement.h>
namespace Kernel {
AK_TYPEDEF_DISTINCT_ORDERED_ID(u64, TimerId);
class Timer final : public AtomicRefCounted<Timer> {
friend class TimerQueue;
public:
void setup(clockid_t clock_id, Time expires, Function<void()>&& callback)
{
VERIFY(!is_queued());
m_clock_id = clock_id;
m_expires = expires;
m_callback = move(callback);
}
~Timer()
{
VERIFY(!is_queued());
}
Time remaining() const;
private:
TimerId m_id;
clockid_t m_clock_id;
Time m_expires;
Time m_remaining {};
Function<void()> m_callback;
Atomic<bool> m_cancelled { false };
Atomic<bool> m_callback_finished { false };
Atomic<bool> m_in_use { false };
bool operator<(Timer const& rhs) const
{
return m_expires < rhs.m_expires;
}
bool operator>(Timer const& rhs) const
{
return m_expires > rhs.m_expires;
}
bool operator==(Timer const& rhs) const
{
return m_id == rhs.m_id;
}
void clear_cancelled() { return m_cancelled.store(false, AK::memory_order_release); }
bool set_cancelled() { return m_cancelled.exchange(true, AK::memory_order_acq_rel); }
bool is_in_use() { return m_in_use.load(AK::memory_order_acquire); };
void set_in_use() { m_in_use.store(true, AK::memory_order_release); }
void clear_in_use() { return m_in_use.store(false, AK::memory_order_release); }
bool is_callback_finished() const { return m_callback_finished.load(AK::memory_order_acquire); }
void clear_callback_finished() { m_callback_finished.store(false, AK::memory_order_release); }
void set_callback_finished() { m_callback_finished.store(true, AK::memory_order_release); }
Time now(bool) const;
bool is_queued() const { return m_list_node.is_in_list(); }
public:
IntrusiveListNode<Timer> m_list_node;
using List = IntrusiveList<&Timer::m_list_node>;
};
class TimerQueue {
friend class Timer;
public:
TimerQueue();
static TimerQueue& the();
TimerId add_timer(NonnullLockRefPtr<Timer>&&);
bool add_timer_without_id(NonnullLockRefPtr<Timer>, clockid_t, Time const&, Function<void()>&&);
bool cancel_timer(Timer& timer, bool* was_in_use = nullptr);
void fire();
private:
struct Queue {
Timer::List list;
Time next_timer_due {};
};
void remove_timer_locked(Queue&, Timer&);
void update_next_timer_due(Queue&);
void add_timer_locked(NonnullLockRefPtr<Timer>);
Queue& queue_for_timer(Timer& timer)
{
switch (timer.m_clock_id) {
case CLOCK_MONOTONIC:
case CLOCK_MONOTONIC_COARSE:
case CLOCK_MONOTONIC_RAW:
return m_timer_queue_monotonic;
case CLOCK_REALTIME:
case CLOCK_REALTIME_COARSE:
return m_timer_queue_realtime;
default:
VERIFY_NOT_REACHED();
}
}
u64 m_timer_id_count { 0 };
u64 m_ticks_per_second { 0 };
Queue m_timer_queue_monotonic;
Queue m_timer_queue_realtime;
Timer::List m_timers_executing;
};
}