ladybird/Kernel/Thread.h

514 lines
15 KiB
C
Raw Normal View History

#pragma once
#include <AK/Function.h>
#include <AK/IntrusiveList.h>
#include <AK/OwnPtr.h>
#include <AK/RefPtr.h>
#include <AK/String.h>
#include <AK/Vector.h>
#include <Kernel/Arch/i386/CPU.h>
#include <Kernel/KResult.h>
#include <Kernel/Scheduler.h>
#include <Kernel/UnixTypes.h>
#include <Kernel/VM/Region.h>
#include <Kernel/WaitQueue.h>
#include <LibC/fd_set.h>
class Alarm;
class FileDescription;
class Process;
class ProcessInspectionHandle;
class Region;
class WaitQueue;
enum class ShouldUnblockThread {
No = 0,
Yes
};
struct SignalActionData {
VirtualAddress handler_or_sigaction;
u32 mask { 0 };
int flags { 0 };
};
struct ThreadSpecificData {
ThreadSpecificData* self;
};
enum class ThreadPriority : u8 {
Idle,
Low,
Normal,
High,
First = Idle,
Last = High,
};
class Thread {
friend class Process;
friend class Scheduler;
public:
explicit Thread(Process&);
~Thread();
static void initialize();
static void finalize_dying_threads();
static Vector<Thread*> all_threads();
static bool is_thread(void*);
int tid() const { return m_tid; }
int pid() const;
void set_priority(ThreadPriority p) { m_priority = p; }
ThreadPriority priority() const { return m_priority; }
void set_joinable(bool j) { m_is_joinable = j; }
bool is_joinable() const { return m_is_joinable; }
Process& process() { return m_process; }
const Process& process() const { return m_process; }
String backtrace(ProcessInspectionHandle&) const;
void finalize();
enum State : u8 {
Invalid = 0,
Runnable,
Running,
Skip1SchedulerPass,
Skip0SchedulerPasses,
Dying,
Dead,
Stopped,
Blocked,
Queued,
};
class Blocker {
public:
virtual ~Blocker() {}
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t now_s, long us) = 0;
virtual const char* state_string() const = 0;
void set_interrupted_by_signal() { m_was_interrupted_while_blocked = true; }
bool was_interrupted_by_signal() const { return m_was_interrupted_while_blocked; }
private:
bool m_was_interrupted_while_blocked { false };
friend class Thread;
};
class JoinBlocker final : public Blocker {
public:
explicit JoinBlocker(Thread& joinee, void*& joinee_exit_value);
virtual bool should_unblock(Thread&, time_t now_s, long us) override;
virtual const char* state_string() const override { return "Joining"; }
void set_joinee_exit_value(void* value) { m_joinee_exit_value = value; }
private:
Thread& m_joinee;
void*& m_joinee_exit_value;
};
class FileDescriptionBlocker : public Blocker {
public:
const FileDescription& blocked_description() const;
protected:
explicit FileDescriptionBlocker(const FileDescription&);
private:
NonnullRefPtr<FileDescription> m_blocked_description;
};
class AcceptBlocker final : public FileDescriptionBlocker {
public:
explicit AcceptBlocker(const FileDescription&);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Accepting"; }
};
class ReceiveBlocker final : public FileDescriptionBlocker {
public:
explicit ReceiveBlocker(const FileDescription&);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Receiving"; }
};
class ConnectBlocker final : public FileDescriptionBlocker {
public:
explicit ConnectBlocker(const FileDescription&);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Connecting"; }
};
class WriteBlocker final : public FileDescriptionBlocker {
public:
explicit WriteBlocker(const FileDescription&);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Writing"; }
};
class ReadBlocker final : public FileDescriptionBlocker {
public:
explicit ReadBlocker(const FileDescription&);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Reading"; }
};
class ConditionBlocker final : public Blocker {
public:
ConditionBlocker(const char* state_string, Function<bool()>&& condition);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return m_state_string; }
private:
Function<bool()> m_block_until_condition;
const char* m_state_string { nullptr };
};
class SleepBlocker final : public Blocker {
2019-07-18 15:26:11 +00:00
public:
explicit SleepBlocker(u64 wakeup_time);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Sleeping"; }
2019-07-18 15:26:11 +00:00
private:
u64 m_wakeup_time { 0 };
};
class SelectBlocker final : public Blocker {
2019-07-18 15:39:49 +00:00
public:
typedef Vector<int, FD_SETSIZE> FDVector;
SelectBlocker(const timeval& tv, bool select_has_timeout, const FDVector& read_fds, const FDVector& write_fds, const FDVector& except_fds);
2019-07-18 15:39:49 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Selecting"; }
2019-07-18 15:39:49 +00:00
private:
timeval m_select_timeout;
bool m_select_has_timeout { false };
const FDVector& m_select_read_fds;
const FDVector& m_select_write_fds;
const FDVector& m_select_exceptional_fds;
2019-07-18 15:39:49 +00:00
};
class WaitBlocker final : public Blocker {
2019-07-18 16:05:19 +00:00
public:
WaitBlocker(int wait_options, pid_t& waitee_pid);
2019-07-18 16:05:19 +00:00
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override { return "Waiting"; }
2019-07-18 16:05:19 +00:00
private:
int m_wait_options { 0 };
pid_t& m_waitee_pid;
};
class SemiPermanentBlocker final : public Blocker {
public:
enum class Reason {
Lurking,
Signal,
};
SemiPermanentBlocker(Reason reason);
virtual bool should_unblock(Thread&, time_t, long) override;
virtual const char* state_string() const override
{
switch (m_reason) {
case Reason::Lurking:
return "Lurking";
case Reason::Signal:
return "Signal";
}
ASSERT_NOT_REACHED();
}
private:
Reason m_reason;
};
void did_schedule() { ++m_times_scheduled; }
u32 times_scheduled() const { return m_times_scheduled; }
bool is_stopped() const { return m_state == Stopped; }
bool is_blocked() const { return m_state == Blocked; }
bool in_kernel() const { return (m_tss.cs & 0x03) == 0; }
u32 frame_ptr() const { return m_tss.ebp; }
u32 stack_ptr() const { return m_tss.esp; }
RegisterDump& get_RegisterDump_from_stack();
u16 selector() const { return m_far_ptr.selector; }
TSS32& tss() { return m_tss; }
const TSS32& tss() const { return m_tss; }
State state() const { return m_state; }
const char* state_string() const;
u32 ticks() const { return m_ticks; }
VirtualAddress thread_specific_data() const { return m_thread_specific_data; }
2019-07-18 15:26:11 +00:00
u64 sleep(u32 ticks);
u64 sleep_until(u64 wakeup_time);
enum class BlockResult {
WokeNormally,
InterruptedBySignal,
};
template<typename T, class... Args>
[[nodiscard]] BlockResult block(Args&&... args)
{
// We should never be blocking a blocked (or otherwise non-active) thread.
ASSERT(state() == Thread::Running);
ASSERT(m_blocker == nullptr);
T t(forward<Args>(args)...);
m_blocker = &t;
set_state(Thread::Blocked);
// Yield to the scheduler, and wait for us to resume unblocked.
yield_without_holding_big_lock();
// We should no longer be blocked once we woke up
ASSERT(state() != Thread::Blocked);
// Remove ourselves...
m_blocker = nullptr;
if (t.was_interrupted_by_signal())
return BlockResult::InterruptedBySignal;
return BlockResult::WokeNormally;
}
[[nodiscard]] BlockResult block_until(const char* state_string, Function<bool()>&& condition)
{
return block<ConditionBlocker>(state_string, move(condition));
}
void wait_on(WaitQueue& queue, Thread* beneficiary = nullptr, const char* reason = nullptr)
{
bool did_unlock = unlock_process_if_locked();
cli();
set_state(State::Queued);
queue.enqueue(*current);
// Yield and wait for the queue to wake us up again.
if (beneficiary)
Scheduler::donate_to(beneficiary, reason);
else
Scheduler::yield();
// We've unblocked, relock the process if needed and carry on.
if (did_unlock)
relock_process();
}
void wake_from_queue()
{
ASSERT(state() == State::Queued);
set_state(State::Runnable);
}
void unblock();
// Tell this thread to unblock if needed,
// gracefully unwind the stack and die.
void set_should_die();
void die_if_needed();
const FarPtr& far_ptr() const { return m_far_ptr; }
bool tick();
void set_ticks_left(u32 t) { m_ticks_left = t; }
u32 ticks_left() const { return m_ticks_left; }
u32 kernel_stack_base() const { return m_kernel_stack_base; }
u32 kernel_stack_top() const { return m_kernel_stack_top; }
void set_selector(u16 s) { m_far_ptr.selector = s; }
void set_state(State);
void send_urgent_signal_to_self(u8 signal);
void send_signal(u8 signal, Process* sender);
void consider_unblock(time_t now_sec, long now_usec);
void set_dump_backtrace_on_finalization() { m_dump_backtrace_on_finalization = true; }
ShouldUnblockThread dispatch_one_pending_signal();
ShouldUnblockThread dispatch_signal(u8 signal);
bool has_unmasked_pending_signals() const;
void terminate_due_to_signal(u8 signal);
bool should_ignore_signal(u8 signal) const;
bool has_signal_handler(u8 signal) const;
FPUState& fpu_state() { return *m_fpu_state; }
bool has_used_fpu() const { return m_has_used_fpu; }
void set_has_used_fpu(bool b) { m_has_used_fpu = b; }
void set_default_signal_dispositions();
void push_value_on_stack(u32);
void make_userspace_stack_for_main_thread(Vector<String> arguments, Vector<String> environment);
void make_thread_specific_region(Badge<Process>);
unsigned syscall_count() const { return m_syscall_count; }
void did_syscall() { ++m_syscall_count; }
unsigned inode_faults() const { return m_inode_faults; }
void did_inode_fault() { ++m_inode_faults; }
unsigned zero_faults() const { return m_zero_faults; }
void did_zero_fault() { ++m_zero_faults; }
unsigned cow_faults() const { return m_cow_faults; }
void did_cow_fault() { ++m_cow_faults; }
Thread* clone(Process&);
template<typename Callback>
static IterationDecision for_each_in_state(State, Callback);
template<typename Callback>
static IterationDecision for_each_living(Callback);
template<typename Callback>
static IterationDecision for_each(Callback);
static bool is_runnable_state(Thread::State state)
{
return state == Thread::State::Running || state == Thread::State::Runnable;
}
static constexpr u32 default_kernel_stack_size = 65536;
static constexpr u32 default_userspace_stack_size = 4 * MB;
private:
IntrusiveListNode m_runnable_list_node;
private:
friend class SchedulerData;
bool unlock_process_if_locked();
void relock_process();
String backtrace_impl() const;
Process& m_process;
int m_tid { -1 };
TSS32 m_tss;
FarPtr m_far_ptr;
u32 m_ticks { 0 };
u32 m_ticks_left { 0 };
u32 m_times_scheduled { 0 };
u32 m_pending_signals { 0 };
u32 m_signal_mask { 0 };
u32 m_kernel_stack_base { 0 };
u32 m_kernel_stack_top { 0 };
Region* m_userspace_stack_region { nullptr };
OwnPtr<Region> m_kernel_stack_region;
VirtualAddress m_thread_specific_data;
SignalActionData m_signal_action_data[32];
Blocker* m_blocker { nullptr };
bool m_is_joinable { true };
Thread* m_joiner { nullptr };
Thread* m_joinee { nullptr };
void* m_exit_value { nullptr };
unsigned m_syscall_count { 0 };
unsigned m_inode_faults { 0 };
unsigned m_zero_faults { 0 };
unsigned m_cow_faults { 0 };
FPUState* m_fpu_state { nullptr };
State m_state { Invalid };
ThreadPriority m_priority { ThreadPriority::Normal };
bool m_has_used_fpu { false };
bool m_dump_backtrace_on_finalization { false };
bool m_should_die { false };
void yield_without_holding_big_lock();
};
HashTable<Thread*>& thread_table();
template<typename Callback>
inline IterationDecision Thread::for_each_living(Callback callback)
{
ASSERT_INTERRUPTS_DISABLED();
return Thread::for_each([callback](Thread& thread) -> IterationDecision {
if (thread.state() != Thread::State::Dead && thread.state() != Thread::State::Dying)
return callback(thread);
return IterationDecision::Continue;
});
}
template<typename Callback>
inline IterationDecision Thread::for_each(Callback callback)
{
ASSERT_INTERRUPTS_DISABLED();
auto ret = Scheduler::for_each_runnable(callback);
if (ret == IterationDecision::Break)
return ret;
return Scheduler::for_each_nonrunnable(callback);
}
template<typename Callback>
inline IterationDecision Thread::for_each_in_state(State state, Callback callback)
{
ASSERT_INTERRUPTS_DISABLED();
auto new_callback = [=](Thread& thread) -> IterationDecision {
if (thread.state() == state)
return callback(thread);
return IterationDecision::Continue;
};
if (is_runnable_state(state))
return Scheduler::for_each_runnable(new_callback);
return Scheduler::for_each_nonrunnable(new_callback);
}
const LogStream& operator<<(const LogStream&, const Thread&);
struct SchedulerData {
typedef IntrusiveList<Thread, &Thread::m_runnable_list_node> ThreadList;
ThreadList m_runnable_threads;
ThreadList m_nonrunnable_threads;
ThreadList& thread_list_for_state(Thread::State state)
{
if (Thread::is_runnable_state(state))
return m_runnable_threads;
return m_nonrunnable_threads;
}
};
template<typename Callback>
inline IterationDecision Scheduler::for_each_runnable(Callback callback)
{
ASSERT_INTERRUPTS_DISABLED();
auto& tl = g_scheduler_data->m_runnable_threads;
for (auto it = tl.begin(); it != tl.end();) {
auto& thread = *it;
it = ++it;
if (callback(thread) == IterationDecision::Break)
return IterationDecision::Break;
}
return IterationDecision::Continue;
}
template<typename Callback>
inline IterationDecision Scheduler::for_each_nonrunnable(Callback callback)
{
ASSERT_INTERRUPTS_DISABLED();
auto& tl = g_scheduler_data->m_nonrunnable_threads;
for (auto it = tl.begin(); it != tl.end();) {
auto& thread = *it;
it = ++it;
if (callback(thread) == IterationDecision::Break)
return IterationDecision::Break;
}
return IterationDecision::Continue;
}
u16 thread_specific_selector();
Descriptor& thread_specific_descriptor();