ladybird/Kernel/TimerQueue.cpp

124 lines
3.7 KiB
C++
Raw Normal View History

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Function.h>
#include <AK/NonnullOwnPtr.h>
#include <AK/OwnPtr.h>
#include <Kernel/Scheduler.h>
#include <Kernel/Time/TimeManagement.h>
#include <Kernel/TimerQueue.h>
namespace Kernel {
static TimerQueue* s_the;
TimerQueue& TimerQueue::the()
{
if (!s_the)
s_the = new TimerQueue;
return *s_the;
}
TimerQueue::TimerQueue()
{
m_ticks_per_second = TimeManagement::the().ticks_per_second();
}
TimerId TimerQueue::add_timer(NonnullOwnPtr<Timer>&& timer)
{
u64 timer_expiration = timer->expires;
ASSERT(timer_expiration >= g_uptime);
timer->id = ++m_timer_id_count;
if (m_timer_queue.is_empty()) {
m_timer_queue.append(move(timer));
m_next_timer_due = timer_expiration;
} else {
auto following_timer = m_timer_queue.find([&timer_expiration](auto& other) { return other->expires > timer_expiration; });
if (following_timer.is_end()) {
m_timer_queue.append(move(timer));
} else {
auto next_timer_needs_update = following_timer.is_begin();
m_timer_queue.insert_before(following_timer, move(timer));
if (next_timer_needs_update)
m_next_timer_due = timer_expiration;
}
}
return m_timer_id_count;
}
TimerId TimerQueue::add_timer(timeval& deadline, Function<void()>&& callback)
{
NonnullOwnPtr timer = make<Timer>();
timer->expires = g_uptime + seconds_to_ticks(deadline.tv_sec) + microseconds_to_ticks(deadline.tv_usec);
timer->callback = move(callback);
return add_timer(move(timer));
}
bool TimerQueue::cancel_timer(TimerId id)
{
auto it = m_timer_queue.find([id](auto& timer) { return timer->id == id; });
if (it.is_end())
return false;
auto was_next_timer = it.is_begin();
m_timer_queue.remove(it);
if (was_next_timer)
update_next_timer_due();
return true;
}
void TimerQueue::fire()
{
if (m_timer_queue.is_empty())
return;
ASSERT(m_next_timer_due == m_timer_queue.first()->expires);
while (!m_timer_queue.is_empty() && g_uptime > m_timer_queue.first()->expires) {
auto timer = m_timer_queue.take_first();
timer->callback();
}
update_next_timer_due();
}
void TimerQueue::update_next_timer_due()
{
if (m_timer_queue.is_empty())
m_next_timer_due = 0;
else
m_next_timer_due = m_timer_queue.first()->expires;
}
}