/****************************************************************************** * Copyright (c) 2015-2024 jiangxiaogang * * This file is part of KLite distribution. * * KLite is free software, you can redistribute it and/or modify it under * the MIT Licence. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. ******************************************************************************/ #include "internal.h" #include "kernel.h" #include "list.h" struct tcb *sched_tcb_now; struct tcb *sched_tcb_next; static struct tcb_list m_list_ready[THREAD_PRIORITY_HIGHEST + 1]; static struct tcb_list m_list_sleep; static uint32_t m_idle_elapse; static uint32_t m_idle_timeout; static uint32_t m_prio_highest; static uint32_t m_prio_bitmap; static void list_insert_by_priority(struct tcb_list *list, struct tcb_node *node) { uint32_t prio; struct tcb_node *find; prio = node->tcb->prio; for(find = list->tail; find != NULL; find = find->prev) { if(find->tcb->prio >= prio) { break; } } list_insert_after(list, find, node); } static uint32_t find_highest_priority(uint32_t highest) { for(; highest > 0; highest--) { if(m_prio_bitmap & (1 << highest)) { break; } } return highest; } void sched_tcb_remove(struct tcb *tcb) { if(tcb->list_wait) { list_remove(tcb->list_wait, &tcb->node_wait); tcb->list_wait = NULL; } if(tcb->list_sched) { list_remove(tcb->list_sched, &tcb->node_sched); if(tcb->list_sched != &m_list_sleep) /* in ready list ? */ { if(tcb->list_sched->head == NULL) { m_prio_bitmap &= ~(1 << tcb->prio); m_prio_highest = find_highest_priority(m_prio_highest); } } tcb->list_sched = NULL; } } void sched_tcb_reset(struct tcb *tcb, uint32_t prio) { if(tcb->list_wait) { list_remove(tcb->list_wait, &tcb->node_wait); list_insert_by_priority(tcb->list_wait, &tcb->node_wait); } if(tcb->list_sched) { if(tcb->list_sched != &m_list_sleep) /* in ready list ? */ { /* remove from old list */ list_remove(tcb->list_sched, &tcb->node_sched); if(tcb->list_sched->head == NULL) { m_prio_bitmap &= ~(1 << tcb->prio); m_prio_highest = find_highest_priority(m_prio_highest); } /* append to new list */ tcb->list_sched = &m_list_ready[prio]; list_append(tcb->list_sched, &tcb->node_sched); m_prio_bitmap |= (1 << prio); if(m_prio_highest < prio) { m_prio_highest = prio; } } } } void sched_tcb_ready(struct tcb *tcb) { tcb->list_sched = &m_list_ready[tcb->prio]; list_append(tcb->list_sched, &tcb->node_sched); m_prio_bitmap |= (1 << tcb->prio); if(m_prio_highest < tcb->prio) { m_prio_highest = tcb->prio; } } void sched_tcb_sleep(struct tcb *tcb, uint32_t timeout) { tcb->timeout = timeout + m_idle_elapse; /* Be careful tcb->timeout overflow! */ tcb->list_sched = &m_list_sleep; list_append(tcb->list_sched, &tcb->node_sched); if(tcb->timeout < m_idle_timeout) { m_idle_timeout = tcb->timeout; } } void sched_tcb_wait(struct tcb *tcb, struct tcb_list *list) { tcb->list_wait = list; list_insert_by_priority(list, &tcb->node_wait); } void sched_tcb_timed_wait(struct tcb *tcb, struct tcb_list *list, uint32_t timeout) { sched_tcb_wait(tcb, list); sched_tcb_sleep(tcb, timeout); } static void sched_tcb_wake_up(struct tcb *tcb) { if(tcb->list_wait) { list_remove(tcb->list_wait, &tcb->node_wait); tcb->list_wait = NULL; } if(tcb->list_sched) { list_remove(tcb->list_sched, &tcb->node_sched); } sched_tcb_ready(tcb); } struct tcb *sched_tcb_wake_from(struct tcb_list *list) { struct tcb *tcb; if(list->head) { tcb = list->head->tcb; sched_tcb_wake_up(tcb); return tcb; } return NULL; } void sched_switch(void) { struct tcb *tcb; tcb = m_list_ready[m_prio_highest].head->tcb; list_remove(tcb->list_sched, &tcb->node_sched); if(tcb->list_sched->head == NULL) { m_prio_bitmap &= ~(1 << tcb->prio); m_prio_highest = find_highest_priority(m_prio_highest); } tcb->list_sched = NULL; sched_tcb_next = tcb; cpu_contex_switch(); } void sched_preempt(bool round_robin) { if(m_prio_bitmap == 0) /* ready list empty */ { return; } if(sched_tcb_now != sched_tcb_next) /* last switch was not completed */ { return; } if((m_prio_highest + round_robin) > sched_tcb_now->prio) { sched_tcb_ready(sched_tcb_now); sched_switch(); } } static void sched_timeout(void) { struct tcb *tcb; struct tcb_node *node; struct tcb_node *next; m_idle_timeout = UINT32_MAX; for(node = m_list_sleep.head; node != NULL; node = next) { next = node->next; tcb = node->tcb; if(tcb->timeout > m_idle_elapse) { tcb->timeout -= m_idle_elapse; if(tcb->timeout < m_idle_timeout) { m_idle_timeout = tcb->timeout; } } else { tcb->timeout = 0; sched_tcb_wake_up(tcb); } } } void sched_timing(uint32_t time) { m_idle_elapse += time; sched_tcb_now->time += time; if(m_idle_elapse >= m_idle_timeout) { sched_timeout(); m_idle_elapse = 0; } } void sched_idle(void) { if(m_prio_bitmap != 0) { sched_tcb_ready(sched_tcb_now); sched_switch(); } else { cpu_sys_sleep(m_idle_timeout); } } void sched_init(void) { m_idle_elapse = 0; m_idle_timeout = UINT32_MAX; m_prio_highest = 0; m_prio_bitmap = 0; sched_tcb_now = NULL; sched_tcb_next = sched_tcb_now - 1; /* mark the last switch was not completed */ memset(m_list_ready, 0, sizeof(m_list_ready)); memset(&m_list_sleep, 0, sizeof(m_list_sleep)); }