ladybird/Kernel/Scheduler.h
kleines Filmröllchen a6a439243f Kernel: Turn lock ranks into template parameters
This step would ideally not have been necessary (increases amount of
refactoring and templates necessary, which in turn increases build
times), but it gives us a couple of nice properties:
- SpinlockProtected inside Singleton (a very common combination) can now
  obtain any lock rank just via the template parameter. It was not
  previously possible to do this with SingletonInstanceCreator magic.
- SpinlockProtected's lock rank is now mandatory; this is the majority
  of cases and allows us to see where we're still missing proper ranks.
- The type already informs us what lock rank a lock has, which aids code
  readability and (possibly, if gdb cooperates) lock mismatch debugging.
- The rank of a lock can no longer be dynamic, which is not something we
  wanted in the first place (or made use of). Locks randomly changing
  their rank sounds like a disaster waiting to happen.
- In some places, we might be able to statically check that locks are
  taken in the right order (with the right lock rank checking
  implementation) as rank information is fully statically known.

This refactoring even more exposes the fact that Mutex has no lock rank
capabilites, which is not fixed here.
2023-01-02 18:15:27 -05:00

60 lines
1.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Assertions.h>
#include <AK/Function.h>
#include <AK/IntrusiveList.h>
#include <AK/Types.h>
#include <Kernel/Forward.h>
#include <Kernel/Locking/Spinlock.h>
#include <Kernel/Time/TimeManagement.h>
#include <Kernel/UnixTypes.h>
namespace Kernel {
struct RegisterState;
extern Thread* g_finalizer;
extern WaitQueue* g_finalizer_wait_queue;
extern Atomic<bool> g_finalizer_has_work;
extern RecursiveSpinlock<LockRank::None> g_scheduler_lock;
struct TotalTimeScheduled {
u64 total { 0 };
u64 total_kernel { 0 };
};
class Scheduler {
public:
static void initialize();
static Thread* create_ap_idle_thread(u32 cpu);
static void set_idle_thread(Thread* idle_thread);
static void timer_tick(RegisterState const&);
[[noreturn]] static void start();
static void pick_next();
static void yield();
static void context_switch(Thread*);
static void enter_current(Thread& prev_thread);
static void leave_on_first_switch(InterruptsState);
static void prepare_after_exec();
static void prepare_for_idle_loop();
static Process* colonel();
static void idle_loop(void*);
static void invoke_async();
static void notify_finalizer();
static Thread& pull_next_runnable_thread();
static Thread* peek_next_runnable_thread();
static bool dequeue_runnable_thread(Thread&, bool = false);
static void enqueue_runnable_thread(Thread&);
static void dump_scheduler_state(bool = false);
static bool is_initialized();
static TotalTimeScheduled get_total_time_scheduled();
static void add_time_scheduled(u64, bool);
};
}