Function rt_system_scheduler_start

src/scheduler_mp.c:494–536

* @brief Start the system scheduler and switch to the highest priority thread. * * @note This function will not return after successful execution. * It performs the initial thread switch during system startup. * The scheduler must be initialized before calling this function. * * @note This function has both MP version and UP version. */ * Don't include below in doxygen document

 *          - Performs context switch to the selected thread
 */
void rt_system_scheduler_start(void)
{
    struct rt_thread *to_thread;
    rt_ubase_t highest_ready_priority;

    /*
     * legacy rt_cpus_lock. some bsp codes still use it as for it's critical
     * region. Since scheduler is never touching this, here we just release it
     * on the entry.
     */
    rt_hw_spin_unlock(&_cpus_lock);

    /* ISR will corrupt the coherency of running frame */
    rt_hw_local_irq_disable();

    /*
     * for the accessing of the scheduler context. Noted that we don't have
     * current_thread at this point
     */
    _fast_spin_lock(&_mp_scheduler_lock);

    /* get the thread scheduling to */
    to_thread = _scheduler_get_highest_priority_thread(&highest_ready_priority);
    RT_ASSERT(to_thread);

    /* to_thread is picked to running on current core, so remove it from ready queue */
    _sched_remove_thread_locked(to_thread);

    /* dedigate current core to `to_thread` */
    RT_SCHED_CTX(to_thread).oncpu = rt_hw_cpu_id();
    RT_SCHED_CTX(to_thread).stat = RT_THREAD_RUNNING;

    LOG_D("[cpu#%d] switch to priority#%d thread:%.*s(sp:0x%08x)",
          rt_hw_cpu_id(), RT_SCHED_PRIV(to_thread).current_priority,
          RT_NAME_MAX, to_thread->parent.name, to_thread->sp);

    _fast_spin_unlock(&_mp_scheduler_lock);

    /* switch to new thread */
    rt_hw_context_switch_to((rt_ubase_t)&to_thread->sp, to_thread);

    /* never come back */
}

/**
 * @brief This function will handle IPI interrupt and do a scheduling in system.