/******************************************************************************** * sched/timer_settime.c * * Copyright (C) 2007-2010, 2013-2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ********************************************************************************/ /******************************************************************************** * Included Files ********************************************************************************/ #include #include #include #include #include #include "os_internal.h" #include "clock_internal.h" #include "sig_internal.h" #include "timer_internal.h" #ifndef CONFIG_DISABLE_POSIX_TIMERS /******************************************************************************** * Definitions ********************************************************************************/ /******************************************************************************** * Private Data ********************************************************************************/ /******************************************************************************** * Public Data ********************************************************************************/ /******************************************************************************** * Private Function Prototypes ********************************************************************************/ static inline void timer_sigqueue(FAR struct posix_timer_s *timer); static inline void timer_restart(FAR struct posix_timer_s *timer, uint32_t itimer); static void timer_timeout(int argc, uint32_t itimer); /******************************************************************************** * Private Functions ********************************************************************************/ /******************************************************************************** * Name: timer_sigqueue * * Description: * This function basically reimplements sigqueue() so that the si_code can * be correctly set to SI_TIMER * * Parameters: * timer - A reference to the POSIX timer that just timed out * * Return Value: * None * * Assumptions: * This function executes in the context of the watchod timer interrupt. * ********************************************************************************/ static inline void timer_sigqueue(FAR struct posix_timer_s *timer) { siginfo_t info; /* Create the siginfo structure */ info.si_signo = timer->pt_signo; info.si_code = SI_TIMER; #ifdef CONFIG_CAN_PASS_STRUCTS info.si_value = timer->pt_value; #else info.si_value.sival_ptr = timer->pt_value.sival_ptr; #endif #ifdef CONFIG_SCHED_HAVE_PARENT info.si_pid = 0; /* Not applicable */ info.si_status = OK; #endif /* Send the signal */ (void)sig_dispatch(timer->pt_owner, &info); } /******************************************************************************** * Name: timer_restart * * Description: * If a periodic timer has been selected, then restart the watchdog. * * Parameters: * timer - A reference to the POSIX timer that just timed out * * Return Value: * None * * Assumptions: * This function executes in the context of the watchod timer interrupt. * ********************************************************************************/ static inline void timer_restart(FAR struct posix_timer_s *timer, uint32_t itimer) { /* If this is a repetitive timer, then restart the watchdog */ if (timer->pt_delay) { timer->pt_last = timer->pt_delay; (void)wd_start(timer->pt_wdog, timer->pt_delay, (wdentry_t)timer_timeout, 1, itimer); } } /******************************************************************************** * Name: timer_timeout * * Description: * This function is called if the timeout elapses before the condition is * signaled. * * Parameters: * argc - the number of arguments (should be 1) * itimer - A reference to the POSIX timer that just timed out * signo - The signal to use to wake up the task * * Return Value: * None * * Assumptions: * This function executes in the context of the watchod timer interrupt. * ********************************************************************************/ static void timer_timeout(int argc, uint32_t itimer) { #ifndef CONFIG_CAN_PASS_STRUCTS /* On many small machines, pointers are encoded and cannot be simply cast from * uint32_t to struct tcb_s*. The following union works around this (see wdogparm_t). */ union { FAR struct posix_timer_s *timer; uint32_t itimer; } u; u.itimer = itimer; /* Send the specified signal to the specified task. Increment the reference * count on the timer first so that will not be deleted until after the * signal handler returns. */ u.timer->pt_crefs++; timer_sigqueue(u.timer); /* Release the reference. timer_release will return nonzero if the timer * was not deleted. */ if (timer_release(u.timer)) { /* If this is a repetitive timer, the restart the watchdog */ timer_restart(u.timer, itimer); } #else /* (casting to uintptr_t first eliminates complaints on some architectures * where the sizeof uint32_t is different from the size of a pointer). */ FAR struct posix_timer_s *timer = (FAR struct posix_timer_s *)((uintptr_t)itimer); /* Send the specified signal to the specified task. Increment the reference * count on the timer first so that will not be deleted until after the * signal handler returns. */ timer->pt_crefs++; timer_sigqueue(timer); /* Release the reference. timer_release will return nonzero if the timer * was not deleted. */ if (timer_release(timer)) { /* If this is a repetitive timer, the restart the watchdog */ timer_restart(timer, itimer); } #endif } /******************************************************************************** * Public Functions ********************************************************************************/ /******************************************************************************** * Name: timer_settime * * Description: * The timer_settime() function sets the time until the next expiration of the * timer specified by timerid from the it_value member of the value argument * and arm the timer if the it_value member of value is non-zero. If the * specified timer was already armed when timer_settime() is called, this call * will reset the time until next expiration to the value specified. If the * it_value member of value is zero, the timer will be disarmed. The effect * of disarming or resetting a timer with pending expiration notifications is * unspecified. * * If the flag TIMER_ABSTIME is not set in the argument flags, timer_settime() * will behave as if the time until next expiration is set to be equal to the * interval specified by the it_value member of value. That is, the timer will * expire in it_value nanoseconds from when the call is made. If the flag * TIMER_ABSTIME is set in the argument flags, timer_settime() will behave as * if the time until next expiration is set to be equal to the difference between * the absolute time specified by the it_value member of value and the current * value of the clock associated with timerid. That is, the timer will expire * when the clock reaches the value specified by the it_value member of value. * If the specified time has already passed, the function will succeed and the * expiration notification will be made. * * The reload value of the timer will be set to the value specified by the * it_interval member of value. When a timer is armed with a non-zero * it_interval, a periodic (or repetitive) timer is specified. * * Time values that are between two consecutive non-negative integer multiples * of the resolution of the specified timer will be rounded up to the larger * multiple of the resolution. Quantization error will not cause the timer to * expire earlier than the rounded time value. * * If the argument ovalue is not NULL, the timer_settime() function will store, * in the location referenced by ovalue, a value representing the previous * amount of time before the timer would have expired, or zero if the timer was * disarmed, together with the previous timer reload value. Timers will not * expire before their scheduled time. * * Parameters: * timerid - The pre-thread timer, previously created by the call to * timer_create(), to be be set. * flags - Specifie characteristics of the timer (see above) * value - Specifies the timer value to set * ovalue - A location in which to return the time remaining from the previous * timer setting. (ignored) * * Return Value: * If the timer_settime() succeeds, a value of 0 (OK) will be returned. * If an error occurs, the value -1 (ERROR) will be returned, and errno set to * indicate the error. * * EINVAL - The timerid argument does not correspond to an ID returned by * timer_create() but not yet deleted by timer_delete(). * EINVAL - A value structure specified a nanosecond value less than zero or * greater than or equal to 1000 million, and the it_value member of that * structure did not specify zero seconds and nanoseconds. * * Assumptions: * ********************************************************************************/ int timer_settime(timer_t timerid, int flags, FAR const struct itimerspec *value, FAR struct itimerspec *ovalue) { FAR struct posix_timer_s *timer = (FAR struct posix_timer_s *)timerid; irqstate_t state; int delay; int ret = OK; /* Some sanity checks */ if (!timer || !value) { errno = EINVAL; return ERROR; } /* Disarm the timer (in case the timer was already armed when timer_settime() * is called). */ (void)wd_cancel(timer->pt_wdog); /* If the it_value member of value is zero, the timer will not be re-armed */ if (value->it_value.tv_sec <= 0 && value->it_value.tv_nsec <= 0) { return OK; } /* Setup up any repititive timer */ if (value->it_interval.tv_sec > 0 || value->it_interval.tv_nsec > 0) { (void)clock_time2ticks(&value->it_interval, &timer->pt_delay); } else { timer->pt_delay = 0; } /* We need to disable timer interrupts through the following section so * that the system timer is stable. */ state = irqsave(); /* Check if abstime is selected */ if ((flags & TIMER_ABSTIME) != 0) { /* Calculate a delay corresponding to the absolute time in 'value'. * NOTE: We have internal knowledge the clock_abstime2ticks only * returns an error if clockid != CLOCK_REALTIME. */ (void)clock_abstime2ticks(CLOCK_REALTIME, &value->it_value, &delay); } else { /* Calculate a delay assuming that 'value' holds the relative time * to wait. We have internal knowledge that clock_time2ticks always * returns success. */ (void)clock_time2ticks(&value->it_value, &delay); } /* If the time is in the past or now, then set up the next interval * instead (assuming a repititive timer). */ if (delay <= 0) { delay = timer->pt_delay; } /* Then start the watchdog */ if (delay > 0) { timer->pt_last = delay; ret = wd_start(timer->pt_wdog, delay, (wdentry_t)timer_timeout, 1, (uint32_t)((uintptr_t)timer)); } irqrestore(state); return ret; } #endif /* CONFIG_DISABLE_POSIX_TIMERS */