rt-thread-official/src/signal.c

652 lines
17 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2017/10/5 Bernard the first version
* 2018/09/17 Jesven fix: in _signal_deliver RT_THREAD_STAT_MASK to RT_THREAD_STAT_SIGNAL_MASK
* 2018/11/22 Jesven in smp version rt_hw_context_switch_to add a param
*/
#include <stdint.h>
#include <string.h>
#include <rthw.h>
#include <rtthread.h>
#ifdef RT_USING_SIGNALS
#ifndef RT_SIG_INFO_MAX
#define RT_SIG_INFO_MAX 32
#endif /* RT_SIG_INFO_MAX */
#define DBG_TAG "SIGN"
#define DBG_LVL DBG_WARNING
#include <rtdbg.h>
#define sig_mask(sig_no) (1u << sig_no)
#define sig_valid(sig_no) (sig_no >= 0 && sig_no < RT_SIG_MAX)
struct siginfo_node
{
siginfo_t si;
struct rt_slist_node list;
};
static struct rt_mempool *_siginfo_pool;
static void _signal_deliver(rt_thread_t tid);
void rt_thread_handle_sig(rt_bool_t clean_state);
static void _signal_default_handler(int signo)
{
LOG_I("handled signo[%d] with default action.", signo);
return ;
}
static void _signal_entry(void *parameter)
{
rt_thread_t tid = rt_thread_self();
/* handle signal */
rt_thread_handle_sig(RT_FALSE);
#ifdef RT_USING_SMP
{
struct rt_cpu* pcpu = rt_cpu_self();
pcpu->current_thread->cpus_lock_nest--;
if (pcpu->current_thread->cpus_lock_nest == 0)
{
pcpu->current_thread->scheduler_lock_nest--;
}
}
#else
/* return to thread */
tid->sp = tid->sig_ret;
tid->sig_ret = RT_NULL;
#endif /* RT_USING_SMP */
LOG_D("switch back to: 0x%08x\n", tid->sp);
tid->stat &= ~RT_THREAD_STAT_SIGNAL;
#ifdef RT_USING_SMP
rt_hw_context_switch_to((rt_base_t)&parameter, tid);
#else
rt_hw_context_switch_to((rt_ubase_t)&(tid->sp));
#endif /* RT_USING_SMP */
}
/*
* To deliver a signal to thread, there are cases:
* 1. When thread is suspended, function resumes thread and
* set signal stat;
* 2. When thread is ready:
* - If function delivers a signal to self thread, just handle
* it.
* - If function delivers a signal to another ready thread, OS
* should build a slice context to handle it.
*/
static void _signal_deliver(rt_thread_t tid)
{
rt_ubase_t level;
level = rt_hw_interrupt_disable();
/* thread is not interested in pended signals */
if (!(tid->sig_pending & tid->sig_mask))
{
rt_hw_interrupt_enable(level);
return;
}
if ((tid->stat & RT_THREAD_STAT_MASK) == RT_THREAD_SUSPEND)
{
/* resume thread to handle signal */
rt_thread_resume(tid);
/* add signal state */
tid->stat |= (RT_THREAD_STAT_SIGNAL | RT_THREAD_STAT_SIGNAL_PENDING);
rt_hw_interrupt_enable(level);
/* re-schedule */
rt_schedule();
}
else
{
if (tid == rt_thread_self())
{
/* add signal state */
tid->stat |= RT_THREAD_STAT_SIGNAL;
rt_hw_interrupt_enable(level);
/* do signal action in self thread context */
if (rt_interrupt_get_nest() == 0)
{
rt_thread_handle_sig(RT_TRUE);
}
}
else if (!((tid->stat & RT_THREAD_STAT_SIGNAL_MASK) & RT_THREAD_STAT_SIGNAL))
{
/* add signal state */
tid->stat |= (RT_THREAD_STAT_SIGNAL | RT_THREAD_STAT_SIGNAL_PENDING);
#ifdef RT_USING_SMP
{
int cpu_id;
cpu_id = tid->oncpu;
if ((cpu_id != RT_CPU_DETACHED) && (cpu_id != rt_hw_cpu_id()))
{
rt_uint32_t cpu_mask;
cpu_mask = RT_CPU_MASK ^ (1 << cpu_id);
rt_hw_ipi_send(RT_SCHEDULE_IPI, cpu_mask);
}
}
#else
/* point to the signal handle entry */
tid->stat &= ~RT_THREAD_STAT_SIGNAL_PENDING;
tid->sig_ret = tid->sp;
tid->sp = rt_hw_stack_init((void *)_signal_entry, RT_NULL,
(void *)((char *)tid->sig_ret - 32), RT_NULL);
#endif /* RT_USING_SMP */
rt_hw_interrupt_enable(level);
LOG_D("signal stack pointer @ 0x%08x", tid->sp);
/* re-schedule */
rt_schedule();
}
else
{
rt_hw_interrupt_enable(level);
}
}
}
#ifdef RT_USING_SMP
void *rt_signal_check(void* context)
{
rt_base_t level;
int cpu_id;
struct rt_cpu* pcpu;
struct rt_thread *current_thread;
level = rt_hw_interrupt_disable();
cpu_id = rt_hw_cpu_id();
pcpu = rt_cpu_index(cpu_id);
current_thread = pcpu->current_thread;
if (pcpu->irq_nest)
{
rt_hw_interrupt_enable(level);
return context;
}
if (current_thread->cpus_lock_nest == 1)
{
if (current_thread->stat & RT_THREAD_STAT_SIGNAL_PENDING)
{
void *sig_context;
current_thread->stat &= ~RT_THREAD_STAT_SIGNAL_PENDING;
rt_hw_interrupt_enable(level);
sig_context = rt_hw_stack_init((void *)_signal_entry, context,
(void *)(context - 32), RT_NULL);
return sig_context;
}
}
rt_hw_interrupt_enable(level);
return context;
}
#endif /* RT_USING_SMP */
/**
* @brief This function will install a processing function to a specific
* signal and return the old processing function of this signal.
*
* @note This function needs to be used in conjunction with the
* rt_signal_unmask() function to make the signal effective.
*
* @see rt_signal_unmask()
*
* @param signo is a specific signal value (range: 0 ~ RT_SIG_MAX).
*
* @param handler is sets the processing of signal value.
*
* @return Return the old processing function of this signal. ONLY When the
* return value is SIG_ERR, the operation is failed.
*/
rt_sighandler_t rt_signal_install(int signo, rt_sighandler_t handler)
{
rt_base_t level;
rt_sighandler_t old = RT_NULL;
rt_thread_t tid = rt_thread_self();
if (!sig_valid(signo)) return SIG_ERR;
level = rt_hw_interrupt_disable();
if (tid->sig_vectors == RT_NULL)
{
rt_thread_alloc_sig(tid);
}
if (tid->sig_vectors)
{
old = tid->sig_vectors[signo];
if (handler == SIG_IGN) tid->sig_vectors[signo] = RT_NULL;
else if (handler == SIG_DFL) tid->sig_vectors[signo] = _signal_default_handler;
else tid->sig_vectors[signo] = handler;
}
rt_hw_interrupt_enable(level);
return old;
}
/**
* @brief This function will block the specified signal.
*
* @note This function will block the specified signal, even if the
* rt_thread_kill() function is called to send this signal to
* the current thread, it will no longer take effect.
*
* @see rt_thread_kill()
*
* @param signo is a specific signal value (range: 0 ~ RT_SIG_MAX).
*/
void rt_signal_mask(int signo)
{
rt_base_t level;
rt_thread_t tid = rt_thread_self();
level = rt_hw_interrupt_disable();
tid->sig_mask &= ~sig_mask(signo);
rt_hw_interrupt_enable(level);
}
/**
* @brief This function will unblock the specified signal.
*
* @note This function will unblock the specified signal. After calling
* the rt_thread_kill() function to send this signal to the current
* thread, it will take effect.
*
* @see rt_thread_kill()
*
* @param signo is a specific signal value (range: 0 ~ RT_SIG_MAX).
*/
void rt_signal_unmask(int signo)
{
rt_base_t level;
rt_thread_t tid = rt_thread_self();
level = rt_hw_interrupt_disable();
tid->sig_mask |= sig_mask(signo);
/* let thread handle pended signals */
if (tid->sig_mask & tid->sig_pending)
{
rt_hw_interrupt_enable(level);
_signal_deliver(tid);
}
else
{
rt_hw_interrupt_enable(level);
}
}
/**
* @brief This function will wait for the arrival of the set signal. If it does not wait for this signal, the thread will be
* suspended until it waits for this signal or the waiting time exceeds the specified timeout: timeout.
*
* @param set is the set of signal values to be waited for. Use the function
* sigaddset() to add the signal.
*
* @param si is a pointer to the received signal info. If you don't care about this value, you can use RT_NULL to set.
*
* @param timeout is a timeout period (unit: an OS tick).
*
* @return Return the operation status. When the return value is RT_EOK, the operation is successful.
* If the return value is any other values, it means that the signal wait failed.
*/
int rt_signal_wait(const rt_sigset_t *set, rt_siginfo_t *si, rt_int32_t timeout)
{
int ret = RT_EOK;
rt_base_t level;
rt_thread_t tid = rt_thread_self();
struct siginfo_node *si_node = RT_NULL, *si_prev = RT_NULL;
/* current context checking */
RT_DEBUG_IN_THREAD_CONTEXT;
/* parameters check */
if (set == NULL || *set == 0 || si == NULL )
{
ret = -RT_EINVAL;
goto __done_return;
}
/* clear siginfo to avoid unknown value */
memset(si, 0x0, sizeof(rt_siginfo_t));
level = rt_hw_interrupt_disable();
/* already pending */
if (tid->sig_pending & *set) goto __done;
if (timeout == 0)
{
ret = -RT_ETIMEOUT;
goto __done_int;
}
/* suspend self thread */
rt_thread_suspend(tid);
/* set thread stat as waiting for signal */
tid->stat |= RT_THREAD_STAT_SIGNAL_WAIT;
/* start timeout timer */
if (timeout != RT_WAITING_FOREVER)
{
/* reset the timeout of thread timer and start it */
rt_timer_control(&(tid->thread_timer),
RT_TIMER_CTRL_SET_TIME,
&timeout);
rt_timer_start(&(tid->thread_timer));
}
rt_hw_interrupt_enable(level);
/* do thread scheduling */
rt_schedule();
level = rt_hw_interrupt_disable();
/* remove signal waiting flag */
tid->stat &= ~RT_THREAD_STAT_SIGNAL_WAIT;
/* check errno of thread */
if (tid->error == -RT_ETIMEOUT)
{
tid->error = RT_EOK;
rt_hw_interrupt_enable(level);
/* timer timeout */
ret = -RT_ETIMEOUT;
goto __done_return;
}
__done:
/* to get the first matched pending signals */
si_node = (struct siginfo_node *)tid->si_list;
while (si_node)
{
int signo;
signo = si_node->si.si_signo;
if (sig_mask(signo) & *set)
{
*si = si_node->si;
LOG_D("sigwait: %d sig raised!", signo);
if (si_prev) si_prev->list.next = si_node->list.next;
else
{
struct siginfo_node *node_next;
if (si_node->list.next)
{
node_next = (void *)rt_slist_entry(si_node->list.next, struct siginfo_node, list);
tid->si_list = node_next;
}
else
{
tid->si_list = RT_NULL;
}
}
/* clear pending */
tid->sig_pending &= ~sig_mask(signo);
rt_mp_free(si_node);
break;
}
si_prev = si_node;
if (si_node->list.next)
{
si_node = (void *)rt_slist_entry(si_node->list.next, struct siginfo_node, list);
}
else
{
si_node = RT_NULL;
}
}
__done_int:
rt_hw_interrupt_enable(level);
__done_return:
return ret;
}
void rt_thread_handle_sig(rt_bool_t clean_state)
{
rt_base_t level;
rt_thread_t tid = rt_thread_self();
struct siginfo_node *si_node;
level = rt_hw_interrupt_disable();
if (tid->sig_pending & tid->sig_mask)
{
/* if thread is not waiting for signal */
if (!(tid->stat & RT_THREAD_STAT_SIGNAL_WAIT))
{
while (tid->sig_pending & tid->sig_mask)
{
int signo, error;
rt_sighandler_t handler;
si_node = (struct siginfo_node *)tid->si_list;
if (!si_node) break;
/* remove this sig info node from list */
if (si_node->list.next == RT_NULL)
tid->si_list = RT_NULL;
else
tid->si_list = (void *)rt_slist_entry(si_node->list.next, struct siginfo_node, list);
signo = si_node->si.si_signo;
handler = tid->sig_vectors[signo];
tid->sig_pending &= ~sig_mask(signo);
rt_hw_interrupt_enable(level);
LOG_D("handle signal: %d, handler 0x%08x", signo, handler);
if (handler) handler(signo);
level = rt_hw_interrupt_disable();
error = -RT_EINTR;
rt_mp_free(si_node); /* release this siginfo node */
/* set errno in thread tcb */
tid->error = error;
}
/* whether clean signal status */
if (clean_state == RT_TRUE)
{
tid->stat &= ~RT_THREAD_STAT_SIGNAL;
}
else
{
return;
}
}
}
rt_hw_interrupt_enable(level);
}
void rt_thread_alloc_sig(rt_thread_t tid)
{
int index;
rt_base_t level;
rt_sighandler_t *vectors;
vectors = (rt_sighandler_t *)RT_KERNEL_MALLOC(sizeof(rt_sighandler_t) * RT_SIG_MAX);
RT_ASSERT(vectors != RT_NULL);
for (index = 0; index < RT_SIG_MAX; index ++)
{
vectors[index] = _signal_default_handler;
}
level = rt_hw_interrupt_disable();
tid->sig_vectors = vectors;
rt_hw_interrupt_enable(level);
}
void rt_thread_free_sig(rt_thread_t tid)
{
rt_base_t level;
struct siginfo_node *si_node;
rt_sighandler_t *sig_vectors;
level = rt_hw_interrupt_disable();
si_node = (struct siginfo_node *)tid->si_list;
tid->si_list = RT_NULL;
sig_vectors = tid->sig_vectors;
tid->sig_vectors = RT_NULL;
rt_hw_interrupt_enable(level);
if (si_node)
{
struct rt_slist_node *node;
struct rt_slist_node *node_to_free;
LOG_D("free signal info list");
node = &(si_node->list);
do
{
node_to_free = node;
node = node->next;
si_node = rt_slist_entry(node_to_free, struct siginfo_node, list);
rt_mp_free(si_node);
} while (node);
}
if (sig_vectors)
{
RT_KERNEL_FREE(sig_vectors);
}
}
/**
* @brief This function can be used to send any signal to any thread.
*
* @param tid is a pointer to the thread that receives the signal.
*
* @param sig is a specific signal value (range: 0 ~ RT_SIG_MAX).
*
* @return Return the operation status. When the return value is RT_EOK, the operation is successful.
* If the return value is any other values, it means that the signal send failed.
*/
int rt_thread_kill(rt_thread_t tid, int sig)
{
siginfo_t si;
rt_base_t level;
struct siginfo_node *si_node;
RT_ASSERT(tid != RT_NULL);
if (!sig_valid(sig)) return -RT_EINVAL;
LOG_I("send signal: %d", sig);
si.si_signo = sig;
si.si_code = SI_USER;
si.si_value.sival_ptr = RT_NULL;
level = rt_hw_interrupt_disable();
if (tid->sig_pending & sig_mask(sig))
{
/* whether already emits this signal? */
struct rt_slist_node *node;
struct siginfo_node *entry;
si_node = (struct siginfo_node *)tid->si_list;
if (si_node)
node = (struct rt_slist_node *)&si_node->list;
else
node = RT_NULL;
/* update sig info */
for (; (node) != RT_NULL; node = node->next)
{
entry = rt_slist_entry(node, struct siginfo_node, list);
if (entry->si.si_signo == sig)
{
memcpy(&(entry->si), &si, sizeof(siginfo_t));
rt_hw_interrupt_enable(level);
return 0;
}
}
}
rt_hw_interrupt_enable(level);
si_node = (struct siginfo_node *) rt_mp_alloc(_siginfo_pool, 0);
if (si_node)
{
rt_slist_init(&(si_node->list));
memcpy(&(si_node->si), &si, sizeof(siginfo_t));
level = rt_hw_interrupt_disable();
if (tid->si_list)
{
struct siginfo_node *si_list;
si_list = (struct siginfo_node *)tid->si_list;
rt_slist_append(&(si_list->list), &(si_node->list));
}
else
{
tid->si_list = si_node;
}
/* a new signal */
tid->sig_pending |= sig_mask(sig);
rt_hw_interrupt_enable(level);
}
else
{
LOG_E("The allocation of signal info node failed.");
}
/* deliver signal to this thread */
_signal_deliver(tid);
return RT_EOK;
}
int rt_system_signal_init(void)
{
_siginfo_pool = rt_mp_create("signal", RT_SIG_INFO_MAX, sizeof(struct siginfo_node));
if (_siginfo_pool == RT_NULL)
{
LOG_E("create memory pool for signal info failed.");
RT_ASSERT(0);
}
return 0;
}
#endif /* RT_USING_SIGNALS */