From 2b6546c40a7ea7738a3bda81f57e396ab3a305ea Mon Sep 17 00:00:00 2001
From: Ben Wiederhake <BenWiederhake.GitHub@gmx.de>
Date: Sat, 27 Feb 2021 23:56:16 +0100
Subject: [PATCH] Kernel: Make Thread use AK::Time internally

This commit is very invasive, because Thread likes to take a pointer and write
to it. This means that translating between timespec/timeval/Time would have been
more difficult than just changing everything that hands a raw pointer to Thread,
in bulk.
---
 Kernel/Devices/AsyncDeviceRequest.cpp |  2 +-
 Kernel/Devices/AsyncDeviceRequest.h   |  2 +-
 Kernel/Devices/USB/UHCIController.cpp |  6 ++--
 Kernel/Syscalls/alarm.cpp             | 10 +++---
 Kernel/Syscalls/beep.cpp              |  2 +-
 Kernel/Syscalls/clock.cpp             | 11 +++---
 Kernel/Syscalls/futex.cpp             |  4 +--
 Kernel/Syscalls/select.cpp            |  8 ++---
 Kernel/Tasks/SyncTask.cpp             |  2 +-
 Kernel/Thread.cpp                     |  4 +--
 Kernel/Thread.h                       | 49 ++++++---------------------
 Kernel/ThreadBlockers.cpp             | 31 ++++++++++++++---
 Kernel/TimerQueue.cpp                 | 12 +++----
 Kernel/TimerQueue.h                   |  5 ++-
 14 files changed, 66 insertions(+), 82 deletions(-)

diff --git a/Kernel/Devices/AsyncDeviceRequest.cpp b/Kernel/Devices/AsyncDeviceRequest.cpp
index 28e6bea121dcf0..1a4430de3e1a25 100644
--- a/Kernel/Devices/AsyncDeviceRequest.cpp
+++ b/Kernel/Devices/AsyncDeviceRequest.cpp
@@ -68,7 +68,7 @@ void AsyncDeviceRequest::request_finished()
     m_queue.wake_all();
 }
 
-auto AsyncDeviceRequest::wait(timeval* timeout) -> RequestWaitResult
+auto AsyncDeviceRequest::wait(Time* timeout) -> RequestWaitResult
 {
     VERIFY(!m_parent_request);
     auto request_result = get_request_result();
diff --git a/Kernel/Devices/AsyncDeviceRequest.h b/Kernel/Devices/AsyncDeviceRequest.h
index 0577a3aa17fe22..ec3d7c4e92bb9b 100644
--- a/Kernel/Devices/AsyncDeviceRequest.h
+++ b/Kernel/Devices/AsyncDeviceRequest.h
@@ -76,7 +76,7 @@ class AsyncDeviceRequest : public RefCounted<AsyncDeviceRequest> {
 
     void add_sub_request(NonnullRefPtr<AsyncDeviceRequest>);
 
-    [[nodiscard]] RequestWaitResult wait(timeval* = nullptr);
+    [[nodiscard]] RequestWaitResult wait(Time* = nullptr);
 
     void do_start(Badge<Device>)
     {
diff --git a/Kernel/Devices/USB/UHCIController.cpp b/Kernel/Devices/USB/UHCIController.cpp
index 51430d35b1458c..852f389aa96ab7 100644
--- a/Kernel/Devices/USB/UHCIController.cpp
+++ b/Kernel/Devices/USB/UHCIController.cpp
@@ -398,10 +398,8 @@ void UHCIController::do_debug_transfer()
 void UHCIController::spawn_port_proc()
 {
     RefPtr<Thread> usb_hotplug_thread;
-    timespec sleep_time {};
 
-    sleep_time.tv_sec = 1;
-    Process::create_kernel_process(usb_hotplug_thread, "UHCIHotplug", [&, sleep_time] {
+    Process::create_kernel_process(usb_hotplug_thread, "UHCIHotplug", [&] {
         for (;;) {
             for (int port = 0; port < UHCI_ROOT_PORT_COUNT; port++) {
                 u16 port_data = 0;
@@ -448,7 +446,7 @@ void UHCIController::spawn_port_proc()
                     }
                 }
             }
-            (void)Thread::current()->sleep(sleep_time);
+            (void)Thread::current()->sleep(Time::from_seconds(1));
         }
     });
 }
diff --git a/Kernel/Syscalls/alarm.cpp b/Kernel/Syscalls/alarm.cpp
index e195de65fdef23..ff3de1350c0a7e 100644
--- a/Kernel/Syscalls/alarm.cpp
+++ b/Kernel/Syscalls/alarm.cpp
@@ -36,9 +36,8 @@ KResultOr<unsigned> Process::sys$alarm(unsigned seconds)
     if (auto alarm_timer = move(m_alarm_timer)) {
         if (TimerQueue::the().cancel_timer(*alarm_timer)) {
             // The timer hasn't fired. Round up the remaining time (if any)
-            timespec remaining;
-            timespec_add(alarm_timer->remaining(), { 0, 1000000000 - 1 }, remaining);
-            previous_alarm_remaining = remaining.tv_sec;
+            Time remaining = alarm_timer->remaining() + Time::from_nanoseconds(999'999'999);
+            previous_alarm_remaining = remaining.to_truncated_seconds();
         }
         // We had an existing alarm, must return a non-zero value here!
         if (previous_alarm_remaining == 0)
@@ -46,8 +45,9 @@ KResultOr<unsigned> Process::sys$alarm(unsigned seconds)
     }
 
     if (seconds > 0) {
-        auto deadline = TimeManagement::the().current_time(CLOCK_REALTIME_COARSE).value();
-        timespec_add(deadline, { seconds, 0 }, deadline);
+        // FIXME: Should use AK::Time internally
+        auto deadline = Time::from_timespec(TimeManagement::the().current_time(CLOCK_REALTIME_COARSE).value());
+        deadline = deadline + Time::from_seconds(seconds);
         m_alarm_timer = TimerQueue::the().add_timer_without_id(CLOCK_REALTIME_COARSE, deadline, [this]() {
             [[maybe_unused]] auto rc = send_signal(SIGALRM, nullptr);
         });
diff --git a/Kernel/Syscalls/beep.cpp b/Kernel/Syscalls/beep.cpp
index a94df54079e07b..c614a0e47f1e9f 100644
--- a/Kernel/Syscalls/beep.cpp
+++ b/Kernel/Syscalls/beep.cpp
@@ -32,7 +32,7 @@ namespace Kernel {
 KResultOr<int> Process::sys$beep()
 {
     PCSpeaker::tone_on(440);
-    auto result = Thread::current()->sleep({ 0, 200 });
+    auto result = Thread::current()->sleep(Time::from_nanoseconds(200'000'000));
     PCSpeaker::tone_off();
     if (result.was_interrupted())
         return EINTR;
diff --git a/Kernel/Syscalls/clock.cpp b/Kernel/Syscalls/clock.cpp
index 4e780706c4c5b7..d883e6ac04c0bc 100644
--- a/Kernel/Syscalls/clock.cpp
+++ b/Kernel/Syscalls/clock.cpp
@@ -94,13 +94,12 @@ KResultOr<int> Process::sys$clock_nanosleep(Userspace<const Syscall::SC_clock_na
 
     bool was_interrupted;
     if (is_absolute) {
-        // FIXME: Should use AK::Time internally
-        was_interrupted = Thread::current()->sleep_until(params.clock_id, requested_sleep->to_timespec()).was_interrupted();
+        was_interrupted = Thread::current()->sleep_until(params.clock_id, requested_sleep.value()).was_interrupted();
     } else {
-        timespec remaining_sleep;
-        // FIXME: Should use AK::Time internally
-        was_interrupted = Thread::current()->sleep(params.clock_id, requested_sleep->to_timespec(), &remaining_sleep).was_interrupted();
-        if (was_interrupted && params.remaining_sleep && !copy_to_user(params.remaining_sleep, &remaining_sleep))
+        Time remaining_sleep;
+        was_interrupted = Thread::current()->sleep(params.clock_id, requested_sleep.value(), &remaining_sleep).was_interrupted();
+        timespec remaining_sleep_ts = remaining_sleep.to_timespec();
+        if (was_interrupted && params.remaining_sleep && !copy_to_user(params.remaining_sleep, &remaining_sleep_ts))
             return EFAULT;
     }
     if (was_interrupted)
diff --git a/Kernel/Syscalls/futex.cpp b/Kernel/Syscalls/futex.cpp
index 08ec27d49cdbb7..c030a2c59bb2c3 100644
--- a/Kernel/Syscalls/futex.cpp
+++ b/Kernel/Syscalls/futex.cpp
@@ -123,9 +123,7 @@ KResultOr<int> Process::sys$futex(Userspace<const Syscall::SC_futex_params*> use
                 return EFAULT;
             clockid_t clock_id = (params.futex_op & FUTEX_CLOCK_REALTIME) ? CLOCK_REALTIME_COARSE : CLOCK_MONOTONIC_COARSE;
             bool is_absolute = cmd != FUTEX_WAIT;
-            // FIXME: Should use AK::Time internally
-            timespec timeout_copy = timeout_time->to_timespec();
-            timeout = Thread::BlockTimeout(is_absolute, &timeout_copy, nullptr, clock_id);
+            timeout = Thread::BlockTimeout(is_absolute, &timeout_time.value(), nullptr, clock_id);
         }
         if (cmd == FUTEX_WAIT_BITSET && params.val3 == FUTEX_BITSET_MATCH_ANY)
             cmd = FUTEX_WAIT;
diff --git a/Kernel/Syscalls/select.cpp b/Kernel/Syscalls/select.cpp
index 3259e51f077394..0b7014eb8bebe6 100644
--- a/Kernel/Syscalls/select.cpp
+++ b/Kernel/Syscalls/select.cpp
@@ -48,9 +48,7 @@ KResultOr<int> Process::sys$select(Userspace<const Syscall::SC_select_params*> u
         Optional<Time> timeout_time = copy_time_from_user(params.timeout);
         if (!timeout_time.has_value())
             return EFAULT;
-        auto timeout_copy = timeout_time->to_timespec();
-        // FIXME: Should use AK::Time internally
-        timeout = Thread::BlockTimeout(false, &timeout_copy);
+        timeout = Thread::BlockTimeout(false, &timeout_time.value());
     }
 
     auto current_thread = Thread::current();
@@ -156,9 +154,7 @@ KResultOr<int> Process::sys$poll(Userspace<const Syscall::SC_poll_params*> user_
         auto timeout_time = copy_time_from_user(params.timeout);
         if (!timeout_time.has_value())
             return EFAULT;
-        timespec timeout_copy = timeout_time->to_timespec();
-        // FIXME: Should use AK::Time internally
-        timeout = Thread::BlockTimeout(false, &timeout_copy);
+        timeout = Thread::BlockTimeout(false, &timeout_time.value());
     }
 
     sigset_t sigmask = {};
diff --git a/Kernel/Tasks/SyncTask.cpp b/Kernel/Tasks/SyncTask.cpp
index 940790b103add1..78e0002aa4fdad 100644
--- a/Kernel/Tasks/SyncTask.cpp
+++ b/Kernel/Tasks/SyncTask.cpp
@@ -38,7 +38,7 @@ void SyncTask::spawn()
         dbgln("SyncTask is running");
         for (;;) {
             VFS::the().sync();
-            (void)Thread::current()->sleep({ 1, 0 });
+            (void)Thread::current()->sleep(Time::from_seconds(1));
         }
     });
 }
diff --git a/Kernel/Thread.cpp b/Kernel/Thread.cpp
index 70403158115cc2..bd50f16dc9e293 100644
--- a/Kernel/Thread.cpp
+++ b/Kernel/Thread.cpp
@@ -333,13 +333,13 @@ void Thread::relock_process(LockMode previous_locked, u32 lock_count_to_restore)
     }
 }
 
-auto Thread::sleep(clockid_t clock_id, const timespec& duration, timespec* remaining_time) -> BlockResult
+auto Thread::sleep(clockid_t clock_id, const Time& duration, Time* remaining_time) -> BlockResult
 {
     VERIFY(state() == Thread::Running);
     return Thread::current()->block<Thread::SleepBlocker>({}, Thread::BlockTimeout(false, &duration, nullptr, clock_id), remaining_time);
 }
 
-auto Thread::sleep_until(clockid_t clock_id, const timespec& deadline) -> BlockResult
+auto Thread::sleep_until(clockid_t clock_id, const Time& deadline) -> BlockResult
 {
     VERIFY(state() == Thread::Running);
     return Thread::current()->block<Thread::SleepBlocker>({}, Thread::BlockTimeout(true, &deadline, nullptr, clock_id));
diff --git a/Kernel/Thread.h b/Kernel/Thread.h
index 3f73e2591eb55a..a40ee397486667 100644
--- a/Kernel/Thread.h
+++ b/Kernel/Thread.h
@@ -208,44 +208,17 @@ class Thread
             : m_infinite(true)
         {
         }
-        explicit BlockTimeout(bool is_absolute, const timeval* time, const timespec* start_time = nullptr, clockid_t clock_id = CLOCK_MONOTONIC_COARSE)
-            : m_clock_id(clock_id)
-            , m_infinite(!time)
-        {
-            if (!m_infinite) {
-                if (time->tv_sec > 0 || time->tv_usec > 0) {
-                    timeval_to_timespec(*time, m_time);
-                    m_should_block = true;
-                }
-                m_start_time = start_time ? *start_time : TimeManagement::the().current_time(clock_id).value();
-                if (!is_absolute)
-                    timespec_add(m_time, m_start_time, m_time);
-            }
-        }
-        explicit BlockTimeout(bool is_absolute, const timespec* time, const timespec* start_time = nullptr, clockid_t clock_id = CLOCK_MONOTONIC_COARSE)
-            : m_clock_id(clock_id)
-            , m_infinite(!time)
-        {
-            if (!m_infinite) {
-                if (time->tv_sec > 0 || time->tv_nsec > 0) {
-                    m_time = *time;
-                    m_should_block = true;
-                }
-                m_start_time = start_time ? *start_time : TimeManagement::the().current_time(clock_id).value();
-                if (!is_absolute)
-                    timespec_add(m_time, m_start_time, m_time);
-            }
-        }
+        explicit BlockTimeout(bool is_absolute, const Time* time, const Time* start_time = nullptr, clockid_t clock_id = CLOCK_MONOTONIC_COARSE);
 
-        const timespec& absolute_time() const { return m_time; }
-        const timespec* start_time() const { return !m_infinite ? &m_start_time : nullptr; }
+        const Time& absolute_time() const { return m_time; }
+        const Time* start_time() const { return !m_infinite ? &m_start_time : nullptr; }
         clockid_t clock_id() const { return m_clock_id; }
         bool is_infinite() const { return m_infinite; }
         bool should_block() const { return m_infinite || m_should_block; };
 
     private:
-        timespec m_time { 0, 0 };
-        timespec m_start_time { 0, 0 };
+        Time m_time {};
+        Time m_start_time {};
         clockid_t m_clock_id { CLOCK_MONOTONIC_COARSE };
         bool m_infinite { false };
         bool m_should_block { false };
@@ -640,7 +613,7 @@ class Thread
 
     class SleepBlocker final : public Blocker {
     public:
-        explicit SleepBlocker(const BlockTimeout&, timespec* = nullptr);
+        explicit SleepBlocker(const BlockTimeout&, Time* = nullptr);
         virtual const char* state_string() const override { return "Sleeping"; }
         virtual Type blocker_type() const override { return Type::Sleep; }
         virtual const BlockTimeout& override_timeout(const BlockTimeout&) override;
@@ -652,7 +625,7 @@ class Thread
         void calculate_remaining();
 
         BlockTimeout m_deadline;
-        timespec* m_remaining;
+        Time* m_remaining;
     };
 
     class SelectBlocker final : public FileBlocker {
@@ -955,13 +928,13 @@ class Thread
         return block<Thread::QueueBlocker>(timeout, wait_queue, forward<Args>(args)...);
     }
 
-    BlockResult sleep(clockid_t, const timespec&, timespec* = nullptr);
-    BlockResult sleep(const timespec& duration, timespec* remaining_time = nullptr)
+    BlockResult sleep(clockid_t, const Time&, Time* = nullptr);
+    BlockResult sleep(const Time& duration, Time* remaining_time = nullptr)
     {
         return sleep(CLOCK_MONOTONIC_COARSE, duration, remaining_time);
     }
-    BlockResult sleep_until(clockid_t, const timespec&);
-    BlockResult sleep_until(const timespec& duration)
+    BlockResult sleep_until(clockid_t, const Time&);
+    BlockResult sleep_until(const Time& duration)
     {
         return sleep_until(CLOCK_MONOTONIC_COARSE, duration);
     }
diff --git a/Kernel/ThreadBlockers.cpp b/Kernel/ThreadBlockers.cpp
index 3d56052c499af4..158dee88628550 100644
--- a/Kernel/ThreadBlockers.cpp
+++ b/Kernel/ThreadBlockers.cpp
@@ -33,6 +33,22 @@
 
 namespace Kernel {
 
+Thread::BlockTimeout::BlockTimeout(bool is_absolute, const Time* time, const Time* start_time, clockid_t clock_id)
+    : m_clock_id(clock_id)
+    , m_infinite(!time)
+{
+    if (!m_infinite) {
+        if (*time > Time::zero()) {
+            m_time = *time;
+            m_should_block = true;
+        }
+        // FIXME: Should use AK::Time internally
+        m_start_time = start_time ? *start_time : Time::from_timespec(TimeManagement::the().current_time(clock_id).value());
+        if (!is_absolute)
+            m_time = m_time + m_start_time;
+    }
+}
+
 bool Thread::Blocker::set_block_condition(Thread::BlockCondition& block_condition, void* data)
 {
     VERIFY(!m_block_condition);
@@ -270,7 +286,9 @@ auto Thread::WriteBlocker::override_timeout(const BlockTimeout& timeout) -> cons
     if (description.is_socket()) {
         auto& socket = *description.socket();
         if (socket.has_send_timeout()) {
-            m_timeout = BlockTimeout(false, &socket.send_timeout(), timeout.start_time(), timeout.clock_id());
+            // FIXME: Should use AK::Time internally
+            Time send_timeout = Time::from_timeval(socket.send_timeout());
+            m_timeout = BlockTimeout(false, &send_timeout, timeout.start_time(), timeout.clock_id());
             if (timeout.is_infinite() || (!m_timeout.is_infinite() && m_timeout.absolute_time() < timeout.absolute_time()))
                 return m_timeout;
         }
@@ -289,7 +307,9 @@ auto Thread::ReadBlocker::override_timeout(const BlockTimeout& timeout) -> const
     if (description.is_socket()) {
         auto& socket = *description.socket();
         if (socket.has_receive_timeout()) {
-            m_timeout = BlockTimeout(false, &socket.receive_timeout(), timeout.start_time(), timeout.clock_id());
+            // FIXME: Should use AK::Time internally
+            Time receive_timeout = Time::from_timeval(socket.receive_timeout());
+            m_timeout = BlockTimeout(false, &receive_timeout, timeout.start_time(), timeout.clock_id());
             if (timeout.is_infinite() || (!m_timeout.is_infinite() && m_timeout.absolute_time() < timeout.absolute_time()))
                 return m_timeout;
         }
@@ -297,7 +317,7 @@ auto Thread::ReadBlocker::override_timeout(const BlockTimeout& timeout) -> const
     return timeout;
 }
 
-Thread::SleepBlocker::SleepBlocker(const BlockTimeout& deadline, timespec* remaining)
+Thread::SleepBlocker::SleepBlocker(const BlockTimeout& deadline, Time* remaining)
     : m_deadline(deadline)
     , m_remaining(remaining)
 {
@@ -329,9 +349,10 @@ void Thread::SleepBlocker::calculate_remaining()
 {
     if (!m_remaining)
         return;
-    auto time_now = TimeManagement::the().current_time(m_deadline.clock_id()).value();
+    // FIXME: Should use AK::Time internally
+    auto time_now = Time::from_timespec(TimeManagement::the().current_time(m_deadline.clock_id()).value());
     if (time_now < m_deadline.absolute_time())
-        timespec_sub(m_deadline.absolute_time(), time_now, *m_remaining);
+        *m_remaining = m_deadline.absolute_time() - time_now;
     else
         *m_remaining = {};
 }
diff --git a/Kernel/TimerQueue.cpp b/Kernel/TimerQueue.cpp
index 3edd86f46ba4a4..fedba303f8c6fd 100644
--- a/Kernel/TimerQueue.cpp
+++ b/Kernel/TimerQueue.cpp
@@ -38,10 +38,9 @@ namespace Kernel {
 static AK::Singleton<TimerQueue> s_the;
 static SpinLock<u8> g_timerqueue_lock;
 
-timespec Timer::remaining() const
+Time Timer::remaining() const
 {
-    // FIXME: Should use AK::Time internally
-    return m_remaining.to_timespec();
+    return m_remaining;
 }
 
 Time Timer::now(bool is_firing) const
@@ -79,9 +78,10 @@ UNMAP_AFTER_INIT TimerQueue::TimerQueue()
     m_ticks_per_second = TimeManagement::the().ticks_per_second();
 }
 
-RefPtr<Timer> TimerQueue::add_timer_without_id(clockid_t clock_id, const timespec& deadline, Function<void()>&& callback)
+RefPtr<Timer> TimerQueue::add_timer_without_id(clockid_t clock_id, const Time& deadline, Function<void()>&& callback)
 {
-    if (deadline <= TimeManagement::the().current_time(clock_id).value())
+    // FIXME: Should use AK::Time internally
+    if (deadline <= Time::from_timespec(TimeManagement::the().current_time(clock_id).value()))
         return {};
 
     // Because timer handlers can execute on any processor and there is
@@ -89,7 +89,7 @@ RefPtr<Timer> TimerQueue::add_timer_without_id(clockid_t clock_id, const timespe
     // *must* be a RefPtr<Timer>. Otherwise calling cancel_timer() could
     // inadvertently cancel another timer that has been created between
     // returning from the timer handler and a call to cancel_timer().
-    auto timer = adopt(*new Timer(clock_id, Time::from_timespec(deadline), move(callback)));
+    auto timer = adopt(*new Timer(clock_id, deadline, move(callback)));
 
     ScopedSpinLock lock(g_timerqueue_lock);
     timer->m_id = 0; // Don't generate a timer id
diff --git a/Kernel/TimerQueue.h b/Kernel/TimerQueue.h
index 9d8f87701d7e32..ea3b3bf88e5d0a 100644
--- a/Kernel/TimerQueue.h
+++ b/Kernel/TimerQueue.h
@@ -55,7 +55,7 @@ class Timer : public RefCounted<Timer>
         VERIFY(!is_queued());
     }
 
-    timespec remaining() const;
+    Time remaining() const;
 
 private:
     TimerId m_id;
@@ -92,8 +92,7 @@ class TimerQueue {
     static TimerQueue& the();
 
     TimerId add_timer(NonnullRefPtr<Timer>&&);
-    // FIXME: Should use AK::Time internally
-    RefPtr<Timer> add_timer_without_id(clockid_t, const timespec&, Function<void()>&&);
+    RefPtr<Timer> add_timer_without_id(clockid_t, const Time&, Function<void()>&&);
     TimerId add_timer(clockid_t, timeval& timeout, Function<void()>&& callback);
     bool cancel_timer(TimerId id);
     bool cancel_timer(Timer&);