OrgApache/incubator-nuttx
OrgApache
/
incubator-nuttx
mirror of https://github.com/apache/incubator-nuttx.git
1
0
Fork 0
Code Issues Releases Wiki Activity
incubator-nuttx/include/nuttx/clock.h

835 lines
27 KiB
C
Raw Blame History

/****************************************************************************
* include/nuttx/clock.h
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_CLOCK_H
#define __INCLUDE_NUTTX_CLOCK_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdbool.h>
#include <stdint.h>
#include <time.h>
#include <nuttx/compiler.h>
#include <nuttx/lib/math32.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Efficient, direct access to OS global timer variables will be supported
* if the execution environment has direct access to kernel global data.
* The code in this execution context can access the kernel global data
* directly if:
*
* 1. We are not running tick-less (in which case there is no global timer
* data),
* 2. This is an un-protected, non-kernel build,
* 3. This is a protected build, but this code is being built for execution
* within the kernel space.
* 4. It we are building with SYSCALLs enabled, but not in a kernel build,
* then we can't know a priori whether the code has access to the
* global variables or not. In that case we have to assume not.
*/
#undef __HAVE_KERNEL_GLOBALS
#if defined(CONFIG_SCHED_TICKLESS)
/* Case 1: There is no global timer data */
#elif defined(__KERNEL__)
/* Case 3: Kernel mode of protected/kernel build */
# define __HAVE_KERNEL_GLOBALS 1
#elif defined(CONFIG_LIB_SYSCALL)
/* Case 4: Building with SYSCALLs enabled, but not part of a kernel build */
#else
/* Case 2: Un-protected, non-kernel build */
# define __HAVE_KERNEL_GLOBALS 1
#endif
/* If CONFIG_SYSTEM_TIME64 is selected and the CPU supports long long types,
* then a 64-bit system time will be used.
*/
#ifndef CONFIG_HAVE_LONG_LONG
# undef CONFIG_SYSTEM_TIME64
#endif
/* The following are the bit fields of the clockid_t
* bit 0~2: the clock type
* CLOCK_REALTIME - 0
* CLOCK_MONOTONIC - 1
* CLOCK_PROCESS_CPUTIME_ID - 2
* CLOCK_THREAD_CPUTIME_ID - 3
* CLOCK_BOOTTIME - 4
* bit 3~32: the pid or tid value
*
* The CLOCK_MASK are using to extract the clock_type from the clockid_t
*/
#define CLOCK_MASK 7
#define CLOCK_SHIFT 3
/* Timing constants *********************************************************/
#define NSEC_PER_SEC 1000000000L /* Seconds */
#define USEC_PER_SEC 1000000L
#define MSEC_PER_SEC 1000
#define DSEC_PER_SEC 10
#define HSEC_PER_SEC 2
#define NSEC_PER_HSEC 500000000L /* Half seconds */
#define USEC_PER_HSEC 500000L
#define MSEC_PER_HSEC 500
#define DSEC_PER_HSEC 5
#define NSEC_PER_DSEC 100000000L /* Deciseconds */
#define USEC_PER_DSEC 100000L
#define MSEC_PER_DSEC 100
#define NSEC_PER_MSEC 1000000L /* Milliseconds */
#define USEC_PER_MSEC 1000
#define NSEC_PER_USEC 1000 /* Microseconds */
#define SEC_PER_MIN 60
#define NSEC_PER_MIN (NSEC_PER_SEC * SEC_PER_MIN)
#define USEC_PER_MIN (USEC_PER_SEC * SEC_PER_MIN)
#define MSEC_PER_MIN (MSEC_PER_SEC * SEC_PER_MIN)
#define DSEC_PER_MIN (DSEC_PER_SEC * SEC_PER_MIN)
#define HSEC_PER_MIN (HSEC_PER_SEC * SEC_PER_MIN)
#define MIN_PER_HOUR 60
#define NSEC_PER_HOUR (NSEC_PER_MIN * MIN_PER_HOUR)
#define USEC_PER_HOUR (USEC_PER_MIN * MIN_PER_HOUR)
#define MSEC_PER_HOUR (MSEC_PER_MIN * MIN_PER_HOUR)
#define DSEC_PER_HOUR (DSEC_PER_MIN * MIN_PER_HOUR)
#define HSEC_PER_HOUR (HSEC_PER_MIN * MIN_PER_HOUR)
#define SEC_PER_HOUR (SEC_PER_MIN * MIN_PER_HOUR)
#define HOURS_PER_DAY 24
#define SEC_PER_DAY (HOURS_PER_DAY * SEC_PER_HOUR)
/* If CONFIG_SCHED_TICKLESS is not defined, then the interrupt interval of
* the system timer is given by USEC_PER_TICK. This is the expected number
* of microseconds between calls from the processor-specific logic to
* nxsched_process_timer(). The default value of USEC_PER_TICK is 10000
* microseconds (100 Hz). However, this default setting can be overridden
* by defining the interval in microseconds as CONFIG_USEC_PER_TICK in the
* NuttX configuration file.
*
* The following calculations are only accurate when (1) there is no
* truncation involved and (2) the underlying system timer is an even
* multiple of microseconds. If (2) is not true, you will probably want
* to redefine all of the following.
*/
#ifdef CONFIG_USEC_PER_TICK
# define USEC_PER_TICK (CONFIG_USEC_PER_TICK)
#else
# define USEC_PER_TICK (10000)
#endif
/* MSEC_PER_TICK can be very inaccurate if CONFIG_USEC_PER_TICK is not an
* even multiple of milliseconds. Calculations using USEC_PER_TICK are
* preferred for that reason (at the risk of overflow)
*/
/* TICK_PER_* truncates! */
#define TICK_PER_HOUR (USEC_PER_HOUR / USEC_PER_TICK)
#define TICK_PER_MIN (USEC_PER_MIN / USEC_PER_TICK)
#define TICK_PER_SEC (USEC_PER_SEC / USEC_PER_TICK)
#define TICK_PER_MSEC (USEC_PER_MSEC / USEC_PER_TICK)
#define TICK_PER_DSEC (USEC_PER_DSEC / USEC_PER_TICK)
#define TICK_PER_HSEC (USEC_PER_HSEC / USEC_PER_TICK)
/* MSEC_PER_TICK truncates! */
#define MSEC_PER_TICK (USEC_PER_TICK / USEC_PER_MSEC)
#define NSEC_PER_TICK (USEC_PER_TICK * NSEC_PER_USEC)
/* ?SEC2TIC rounds up */
#define NSEC2TICK(nsec) div_const_roundup(nsec, NSEC_PER_TICK)
#define USEC2TICK(usec) div_const_roundup(usec, USEC_PER_TICK)
#if (MSEC_PER_TICK * USEC_PER_MSEC) == USEC_PER_TICK
# define MSEC2TICK(msec) div_const_roundup(msec, MSEC_PER_TICK)
#else
# define MSEC2TICK(msec) USEC2TICK((msec) * USEC_PER_MSEC)
#endif
#define DSEC2TICK(dsec) MSEC2TICK((dsec) * MSEC_PER_DSEC)
#define HSEC2TICK(dsec) MSEC2TICK((dsec) * MSEC_PER_HSEC)
#define SEC2TICK(sec) MSEC2TICK((sec) * MSEC_PER_SEC)
#define TICK2NSEC(tick) ((tick) * NSEC_PER_TICK)
#define TICK2USEC(tick) ((tick) * USEC_PER_TICK)
#if (MSEC_PER_TICK * USEC_PER_MSEC) == USEC_PER_TICK
# define TICK2MSEC(tick) ((tick) * MSEC_PER_TICK)
#else
# define TICK2MSEC(tick) div_const(((tick) * USEC_PER_TICK), USEC_PER_MSEC)
#endif
/* TIC2?SEC rounds to nearest */
#define TICK2DSEC(tick) div_const_roundnearest(tick, TICK_PER_DSEC)
#define TICK2HSEC(tick) div_const_roundnearest(tick, TICK_PER_HSEC)
#define TICK2SEC(tick) div_const_roundnearest(tick, TICK_PER_SEC)
/* MSEC2SEC */
#define MSEC2SEC(usec) div_const(msec, MSEC_PER_SEC)
/* USEC2SEC */
#define USEC2SEC(usec) div_const(usec, USEC_PER_SEC)
/* NSEC2USEC */
#define NSEC2USEC(nsec) div_const(nsec, NSEC_PER_USEC)
/* NSEC2MSEC */
#define NSEC2MSEC(nsec) div_const(nsec, NSEC_PER_MSEC)
#if defined(CONFIG_DEBUG_SCHED) && defined(CONFIG_SYSTEM_TIME64) && \
!defined(CONFIG_SCHED_TICKLESS)
/* Initial system timer ticks value close to maximum 32-bit value, to test
* 64-bit system-timer after going over 32-bit value. This is to make errors
* of casting 64-bit system-timer to 32-bit variables more visible.
*/
# define INITIAL_SYSTEM_TIMER_TICKS \
((uint64_t)(UINT32_MAX - (TICK_PER_SEC * 5)))
#else
# define INITIAL_SYSTEM_TIMER_TICKS 0
#endif
/* If Gregorian time is not supported, then neither is Julian */
#ifndef CONFIG_GREGORIAN_TIME
# undef CONFIG_JULIAN_TIME
#else
# define JD_OF_EPOCH 2440588 /* Julian Date of noon, J1970 */
# ifdef CONFIG_JULIAN_TIME
# define GREG_DUTC -141427 /* Default is October 15, 1582 */
# define GREG_YEAR 1582
# define GREG_MONTH 10
# define GREG_DAY 15
# endif /* CONFIG_JULIAN_TIME */
#endif /* !CONFIG_GREGORIAN_TIME */
#define SECSPERMIN 60
#define MINSPERHOUR 60
#define HOURSPERDAY 24
#define DAYSPERWEEK 7
#define DAYSPERNYEAR 365
#define DAYSPERLYEAR 366
#define MONSPERYEAR 12
#define TM_SUNDAY 0
#define TM_MONDAY 1
#define TM_TUESDAY 2
#define TM_WEDNESDAY 3
#define TM_THURSDAY 4
#define TM_FRIDAY 5
#define TM_SATURDAY 6
#define TM_JANUARY 0
#define TM_FEBRUARY 1
#define TM_MARCH 2
#define TM_APRIL 3
#define TM_MAY 4
#define TM_JUNE 5
#define TM_JULY 6
#define TM_AUGUST 7
#define TM_SEPTEMBER 8
#define TM_OCTOBER 9
#define TM_NOVEMBER 10
#define TM_DECEMBER 11
#define TM_YEAR_BASE (1900)
#define TM_WDAY_BASE TM_MONDAY
#define EPOCH_YEAR 1970
#define EPOCH_WDAY TM_THURSDAY
/****************************************************************************
* Public Types
****************************************************************************/
/* This structure is used to report CPU usage for a particular thread */
#ifndef CONFIG_SCHED_CPULOAD_NONE
struct cpuload_s
{
volatile clock_t total; /* Total number of clock ticks */
volatile clock_t active; /* Number of ticks while this thread was active */
};
#endif
/* This non-standard type used to hold relative clock ticks that may take
* negative values. Because of its non-portable nature the type sclock_t
* should be used only within the OS proper and not by portable applications.
*/
#ifdef CONFIG_SYSTEM_TIME64
typedef int64_t sclock_t;
#else
typedef int32_t sclock_t;
#endif
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/* Access to raw system clock ***********************************************/
/* Direct access to the system timer/counter is supported only if (1) the
* system timer counter is available (i.e., we are not configured to use
* a hardware periodic timer), and (2) the execution environment has direct
* access to kernel global data
*/
#ifdef __HAVE_KERNEL_GLOBALS
EXTERN volatile clock_t g_system_ticks;
# ifndef CONFIG_SYSTEM_TIME64
# define clock_systime_ticks() g_system_ticks
# endif
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#define clock_ticks2time(ts, tick) \
do \
{ \
clock_t _tick = (clock_t)(tick); \
(ts)->tv_sec = (time_t)div_const(_tick, TICK_PER_SEC); \
_tick -= (clock_t)(ts)->tv_sec * TICK_PER_SEC; \
(ts)->tv_nsec = (long)_tick * NSEC_PER_TICK; \
} \
while (0)
#define clock_time2ticks(ts) \
((clock_t)(ts)->tv_sec * TICK_PER_SEC + NSEC2TICK((ts)->tv_nsec))
#define clock_usec2time(ts, usec) \
do \
{ \
uint64_t _usec = (usec); \
(ts)->tv_sec = (time_t)div_const(_usec, USEC_PER_SEC); \
_usec -= (uint64_t)(ts)->tv_sec * USEC_PER_SEC; \
(ts)->tv_nsec = (long)_usec * NSEC_PER_USEC; \
} \
while (0)
#define clock_time2usec(ts) \
((uint64_t)(ts)->tv_sec * USEC_PER_SEC + div_const((ts)->tv_nsec, NSEC_PER_USEC))
#define clock_nsec2time(ts, nsec) \
do \
{ \
uint64_t _nsec = (nsec); \
(ts)->tv_sec = (time_t)div_const(_nsec, NSEC_PER_SEC); \
_nsec -= (uint64_t)(ts)->tv_sec * NSEC_PER_SEC; \
(ts)->tv_nsec = (long)_nsec; \
} \
while (0)
#define clock_time2nsec(ts) \
((uint64_t)(ts)->tv_sec * NSEC_PER_SEC + (ts)->tv_nsec)
/****************************************************************************
* Name: clock_timespec_add
*
* Description:
* Add timespec ts1 to to2 and return the result in ts3
*
* Input Parameters:
* ts1 and ts2: The two timespecs to be added
* t23: The location to return the result (may be ts1 or ts2)
*
* Returned Value:
* None
*
****************************************************************************/
#define clock_timespec_add(ts1, ts2, ts3) \
do \
{ \
time_t _sec = (ts1)->tv_sec + (ts2)->tv_sec; \
long _nsec = (ts1)->tv_nsec + (ts2)->tv_nsec; \
if (_nsec >= NSEC_PER_SEC) \
{ \
_nsec -= NSEC_PER_SEC; \
_sec++; \
} \
(ts3)->tv_sec = _sec; \
(ts3)->tv_nsec = _nsec; \
}\
while (0)
/****************************************************************************
* Name: clock_timespec_subtract
*
* Description:
* Subtract timespec ts2 from to1 and return the result in ts3.
* Zero is returned if the time difference is negative.
*
* Input Parameters:
* ts1 and ts2: The two timespecs to be subtracted (ts1 - ts2)
* t23: The location to return the result (may be ts1 or ts2)
*
* Returned Value:
* None
*
****************************************************************************/
#define clock_timespec_subtract(ts1, ts2, ts3) \
do \
{ \
time_t _sec = (ts1)->tv_sec - (ts2)->tv_sec; \
long _nsec = (ts1)->tv_nsec - (ts2)->tv_nsec; \
if (_nsec < 0) \
{ \
_nsec += NSEC_PER_SEC; \
_sec--; \
} \
if ((sclock_t)_sec < 0) \
{ \
_sec = 0; \
_nsec = 0; \
} \
(ts3)->tv_sec = _sec; \
(ts3)->tv_nsec = _nsec; \
}\
while (0)
/****************************************************************************
* Name: clock_timespec_compare
*
* Description:
* Return < 0 if time ts1 is before time ts2
* Return > 0 if time ts2 is before time ts1
* Return 0 if time ts1 is the same as time ts2
*
****************************************************************************/
#define clock_timespec_compare(ts1, ts2) \
(((ts1)->tv_sec < (ts2)->tv_sec) ? -1 : \
((ts1)->tv_sec > (ts2)->tv_sec) ? 1 : \
(ts1)->tv_nsec - (ts2)->tv_nsec)
/****************************************************************************
* Name: clock_abstime2ticks
*
* Description:
* Convert an absolute timespec delay to system timer ticks.
*
* Input Parameters:
* clockid - The timing source to use in the conversion
* abstime - Convert this absolute time to ticks
* ticks - Return the converted number of ticks here.
*
* Returned Value:
* None
*
* Assumptions:
* Interrupts should be disabled so that the time is not changing during
* the calculation
*
****************************************************************************/
#define clock_abstime2ticks(clockid, abstime, ticks) \
do \
{ \
struct timespec _reltime; \
nxclock_gettime(clockid, &_reltime); \
clock_timespec_subtract(abstime, &_reltime, &_reltime); \
*(ticks) = clock_time2ticks(&_reltime); \
} \
while (0)
/****************************************************************************
* Name: clock_realtime2absticks
*
* Description:
* Convert real time to monotonic ticks.
*
* Input Parameters:
* mono - Return the converted time here.
* abstime - Convert this absolute time to ticks
*
* Returned Value:
* OK (0) on success; a negated errno value on failure.
*
* Assumptions:
* Interrupts should be disabled so that the time is not changing during
* the calculation
*
****************************************************************************/
int clock_realtime2absticks(FAR const struct timespec *reltime,
FAR clock_t *absticks);
/****************************************************************************
* Name: clock_compare
*
* Description:
* This function is used for check whether the expired time is reached.
* It take the ticks wrap-around into consideration.
*
* Input Parameters:
* tick1 - Expected time in clock ticks
* tick2 - Current time in clock ticks
*
* Returned Value:
* true - Expected ticks is timeout.
* false - Otherwise.
*
* Assumptions:
* The type of delay value should be sclock_t.
*
****************************************************************************/
/* clock_compare considers tick wraparound, discussed as follows:
* Assuming clock_t is a 64-bit data type.
*
* Case 1: If tick2 - tick1 > 2^63, it is considered expired
* or expired after tick2 wraparound.
*
* Case 2: If tick2 - tick1 <= 2^63,
* it is considered not expired.
*
* For bit-63 as the sign bit, we can simplify this to:
* (sclock_t)(tick2 - tick1) >= 0.
*
* However, this function requires an assumption to work correctly:
* Assumes the timer delay time does not exceed SCLOCK_MAX (2^63 - 1).
*
* The range of the delay data type sclock_t being
* [- (SCLOCK_MAX + 1), SCLOCK_MAX] ensures this assumption holds.
*/
#define clock_compare(tick1, tick2) ((sclock_t)((tick2) - (tick1)) >= 0)
/****************************************************************************
* Name: clock_isleapyear
*
* Description:
* Return true if the specified year is a leap year
*
****************************************************************************/
int clock_isleapyear(int year);
/****************************************************************************
* Name: clock_daysbeforemonth
*
* Description:
* Get the number of days that occurred before the beginning of the month.
*
****************************************************************************/
int clock_daysbeforemonth(int month, bool leapyear);
/****************************************************************************
* Name: clock_dayoftheweek
*
* Description:
* Get the day of the week
*
* Input Parameters:
* mday - The day of the month 1 - 31
* month - The month of the year 1 - 12
* year - the year including the 1900
*
* Returned Value:
* Zero based day of the week 0-6, 0 = Sunday, 1 = Monday... 6 = Saturday
*
****************************************************************************/
int clock_dayoftheweek(int mday, int month, int year);
/****************************************************************************
* Name: clock_calendar2utc
*
* Description:
* Calendar/UTC conversion based on algorithms from p. 604
* of Seidelman, P. K. 1992. Explanatory Supplement to
* the Astronomical Almanac. University Science Books,
* Mill Valley.
*
****************************************************************************/
time_t clock_calendar2utc(int year, int month, int day);
/****************************************************************************
* Name: clock_synchronize
*
* Description:
* Synchronize the system timer to a hardware RTC. This operation is
* normally performed automatically by the system during clock
* initialization. However, the user may also need to explicitly re-
* synchronize the system timer to the RTC under certain conditions where
* the system timer is known to be in error. For example, in certain low-
* power states, the system timer may be stopped but the RTC will continue
* keep correct time. After recovering from such low-power state, this
* function should be called to restore the correct system time.
*
* Calling this function could result in system time going "backward" in
* time, especially with certain lower resolution RTC implementations.
* Time going backward could have bad consequences if there are ongoing
* timers and delays. So use this interface with care.
*
* Input Parameters:
* tp: rtc time should be synced, set NULL to re-get time
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
#ifdef CONFIG_RTC
void clock_synchronize(FAR const struct timespec *tp);
#endif
/****************************************************************************
* Name: clock_resynchronize
*
* Description:
* Resynchronize the system timer to a hardware RTC. The user can
* explicitly re-synchronize the system timer to the RTC under certain
* conditions where the system timer is known to be in error. For example,
* in certain low-power states, the system timer may be stopped but the
* RTC will continue keep correct time. After recovering from such
* low-power state, this function should be called to restore the correct
* system time. Function also keeps monotonic clock at rate of RTC.
*
* Calling this function will not result in system time going "backward" in
* time. If setting system time with RTC would result time going "backward"
* then resynchronization is not performed.
*
* Input Parameters:
* diff: amount of time system-time is adjusted forward with RTC
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
#if defined(CONFIG_RTC) && !defined(CONFIG_SCHED_TICKLESS)
void clock_resynchronize(FAR struct timespec *rtc_diff);
#endif
/****************************************************************************
* Name: clock_systime_ticks
*
* Description:
* Return the current value of the 32/64-bit system timer counter.
*
* Indirect access to the system timer counter is required through this
* function if the execution environment does not have direct access to
* kernel global data.
*
* Use of this function is also required to assure atomic access to the
* 64-bit system timer.
*
* NOTE: This is an internal OS interface and should not be called from
* application code. Rather, the functionally equivalent, standard
* interface clock() should be used.
*
* Input Parameters:
* None
*
* Returned Value:
* The current value of the system timer counter
*
****************************************************************************/
#if !defined(__HAVE_KERNEL_GLOBALS) || defined(CONFIG_SYSTEM_TIME64)
clock_t clock_systime_ticks(void);
#endif
/****************************************************************************
* Name: clock_systime_timespec
*
* Description:
* Return the current value of the system timer counter as a struct
* timespec.
*
* Input Parameters:
* ts - Location to return the time
*
* Returned Value:
* OK (0) on success; a negated errno value on failure.
*
* Assumptions:
*
****************************************************************************/
int clock_systime_timespec(FAR struct timespec *ts);
/****************************************************************************
* Name: clock_cpuload
*
* Description:
* Return load measurement data for the select PID.
*
* Input Parameters:
* pid - The task ID of the thread of interest. pid == 0 is IDLE thread.
* cpuload - The location to return the CPU load
*
* Returned Value:
* OK (0) on success; a negated errno value on failure. The only reason
* that this function can fail is if 'pid' no longer refers to a valid
* thread.
*
* Assumptions:
*
****************************************************************************/
#ifndef CONFIG_SCHED_CPULOAD_NONE
int clock_cpuload(int pid, FAR struct cpuload_s *cpuload);
#endif
/****************************************************************************
* Name: nxsched_oneshot_extclk
*
* Description:
* Configure to use a oneshot timer as described in
* include/nuttx/timers/oneshot.h to provide external clocking to assess
* the CPU load.
*
* Input Parameters:
* lower - An instance of the oneshot timer interface as defined in
* include/nuttx/timers/oneshot.h
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_CPULOAD_ONESHOT
struct oneshot_lowerhalf_s;
void nxsched_oneshot_extclk(FAR struct oneshot_lowerhalf_s *lower);
#endif
/****************************************************************************
* Name: nxsched_period_extclk
*
* Description:
* Configure to use a period timer as described in
* include/nuttx/timers/timer.h to provide external clocking to assess
* the CPU load.
*
* Input Parameters:
* lower - An instance of the period timer interface as defined in
* include/nuttx/timers/timer.h
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_CPULOAD_PERIOD
struct timer_lowerhalf_s;
void nxsched_period_extclk(FAR struct timer_lowerhalf_s *lower);
#endif
/****************************************************************************
* perf_gettime
****************************************************************************/
clock_t perf_gettime(void);
/****************************************************************************
* perf_convert
****************************************************************************/
void perf_convert(clock_t elapsed, FAR struct timespec *ts);
/****************************************************************************
* perf_gettfreq
****************************************************************************/
unsigned long perf_getfreq(void);
/****************************************************************************
* Name: nxclock_settime
*
* Description:
* Clock Functions based on POSIX APIs
*
* CLOCK_REALTIME - POSIX demands this to be present. This is the wall
* time clock.
*
****************************************************************************/
void nxclock_settime(clockid_t clock_id, FAR const struct timespec *tp);
/****************************************************************************
* Name: nxclock_gettime
*
* Description:
* Get the current value of the specified time clock.
*
****************************************************************************/
void nxclock_gettime(clockid_t clock_id, FAR struct timespec *tp);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_CLOCK_H */
Reference in New Issue View Git Blame Copy Permalink