2021-05-16 18:27:01 +08:00

153 lines
4.1 KiB
C

/*
* Copyright (c) 2020 Institute of Parallel And Distributed Systems (IPADS), Shanghai Jiao Tong University (SJTU)
* OS-Lab-2020 (i.e., ChCore) is licensed under the Mulan PSL v1.
* You can use this software according to the terms and conditions of the Mulan PSL v1.
* You may obtain a copy of Mulan PSL v1 at:
* http://license.coscl.org.cn/MulanPSL
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR
* PURPOSE.
* See the Mulan PSL v1 for more details.
*/
/* Scheduler related functions are implemented here */
#include <sched/sched.h>
#include <common/smp.h>
#include <common/kprint.h>
#include <common/machine.h>
#include <common/kmalloc.h>
#include <common/list.h>
#include <common/util.h>
#include <process/thread.h>
#include <common/macro.h>
#include <common/errno.h>
#include <process/thread.h>
#include <exception/irq.h>
#include <sched/context.h>
/* in arch/sched/idle.S */
void idle_thread_routine(void);
/*
* rr_ready_queue
* Per-CPU ready queue for ready tasks.
*/
struct list_head rr_ready_queue[PLAT_CPU_NUM];
/*
* RR policy also has idle threads.
* When no active user threads in ready queue,
* we will choose the idle thread to execute.
* Idle thread will **NOT** be in the RQ.
*/
struct thread idle_threads[PLAT_CPU_NUM];
/*
* Lab4
* Sched_enqueue
* Put `thread` at the end of ready queue of assigned `affinity`.
* If affinity = NO_AFF, assign the core to the current cpu.
* If the thread is IDEL thread, do nothing!
* Do not forget to check if the affinity is valid!
*/
int rr_sched_enqueue(struct thread *thread)
{
return -1;
}
/*
* Lab4
* Sched_dequeue
* remove `thread` from its current residual ready queue
* Do not forget to add some basic parameter checking
*/
int rr_sched_dequeue(struct thread *thread)
{
return -1;
}
/*
* Lab4
* The helper function
* Choose an appropriate thread and dequeue from ready queue
*
* If there is no ready thread in the current CPU's ready queue,
* choose the idle thread of the CPU.
*
* Do not forget to check the type and
* state of the chosen thread
*/
struct thread *rr_sched_choose_thread(void)
{
return NULL;
}
static inline void rr_sched_refill_budget(struct thread *target, u32 budget)
{
}
/*
* Lab4
* Schedule a thread to execute.
* This function will suspend current running thread, if any, and schedule
* another thread from `rr_ready_queue[cpu_id]`.
*
* Hints:
* Macro DEFAULT_BUDGET defines the value for resetting thread's budget.
* After you get one thread from rr_sched_choose_thread, pass it to
* switch_to_thread() to prepare for switch_context().
* Then ChCore can call eret_to_thread() to return to user mode.
*/
int rr_sched(void)
{
return -1;
}
/*
* Initialize the per thread queue and idle thread.
*/
int rr_sched_init(void)
{
int i = 0;
/* Initialize global variables */
for (i = 0; i < PLAT_CPU_NUM; i++) {
current_threads[i] = NULL;
init_list_head(&rr_ready_queue[i]);
}
/* Initialize one idle thread for each core and insert into the RQ */
for (i = 0; i < PLAT_CPU_NUM; i++) {
/* Set the thread context of the idle threads */
BUG_ON(!(idle_threads[i].thread_ctx = create_thread_ctx()));
/* We will set the stack and func ptr in arch_idle_ctx_init */
init_thread_ctx(&idle_threads[i], 0, 0, MIN_PRIO, TYPE_IDLE, i);
/* Call arch-dependent function to fill the context of the idle
* threads */
arch_idle_ctx_init(idle_threads[i].thread_ctx,
idle_thread_routine);
/* Idle thread is kernel thread which do not have vmspace */
idle_threads[i].vmspace = NULL;
}
kdebug("Scheduler initialized. Create %d idle threads.\n", i);
return 0;
}
/*
* Lab4
* Handler called each time a timer interrupt is handled
* Do not forget to call sched_handle_timer_irq() in proper code location.
*/
void rr_sched_handle_timer_irq(void)
{
}
struct sched_ops rr = {
.sched_init = rr_sched_init,
.sched = rr_sched,
.sched_enqueue = rr_sched_enqueue,
.sched_dequeue = rr_sched_dequeue,
.sched_choose_thread = rr_sched_choose_thread,
.sched_handle_timer_irq = rr_sched_handle_timer_irq,
};