You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

169 lines
5.2 KiB
C

/*
ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file rt/src/chtm.c
* @brief Time Measurement module code.
*
* @addtogroup time_measurement
* @details Time Measurement APIs and services.
* @{
*/
#include "ch.h"
#if (CH_CFG_USE_TM == TRUE) || defined(__DOXYGEN__)
/*===========================================================================*/
/* Module local definitions. */
/*===========================================================================*/
/**
* @brief Number of iterations in the calibration loop.
* @note This is required in order to assess the best result in
* architectures with instruction cache.
*/
#define TM_CALIBRATION_LOOP 4U
/*===========================================================================*/
/* Module exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local functions. */
/*===========================================================================*/
static inline void tm_stop(time_measurement_t *tmp,
rtcnt_t now,
rtcnt_t offset) {
tmp->n++;
tmp->last = (now - tmp->last) - offset;
tmp->cumulative += (rttime_t)tmp->last;
if (tmp->last > tmp->worst) {
tmp->worst = tmp->last;
}
if (tmp->last < tmp->best) {
tmp->best = tmp->last;
}
}
/*===========================================================================*/
/* Module exported functions. */
/*===========================================================================*/
/**
* @brief Initializes the time measurement unit.
*
* @init
*/
void _tm_init(void) {
time_measurement_t tm;
unsigned i;
/* Time Measurement subsystem calibration, it does a null measurement
and calculates the call overhead which is subtracted to real
measurements.*/
ch.tm.offset = (rtcnt_t)0;
chTMObjectInit(&tm);
i = TM_CALIBRATION_LOOP;
do {
chTMStartMeasurementX(&tm);
chTMStopMeasurementX(&tm);
i--;
} while (i > 0U);
ch.tm.offset = tm.best;
}
/**
* @brief Initializes a @p TimeMeasurement object.
*
* @param[out] tmp pointer to a @p TimeMeasurement structure
*
* @init
*/
void chTMObjectInit(time_measurement_t *tmp) {
tmp->best = (rtcnt_t)-1;
tmp->worst = (rtcnt_t)0;
tmp->last = (rtcnt_t)0;
tmp->n = (ucnt_t)0;
tmp->cumulative = (rttime_t)0;
}
/**
* @brief Starts a measurement.
* @pre The @p time_measurement_t structure must be initialized.
*
* @param[in,out] tmp pointer to a @p TimeMeasurement structure
*
* @xclass
*/
NOINLINE void chTMStartMeasurementX(time_measurement_t *tmp) {
tmp->last = chSysGetRealtimeCounterX();
}
/**
* @brief Stops a measurement.
* @pre The @p time_measurement_t structure must be initialized.
*
* @param[in,out] tmp pointer to a @p time_measurement_t structure
*
* @xclass
*/
NOINLINE void chTMStopMeasurementX(time_measurement_t *tmp) {
tm_stop(tmp, chSysGetRealtimeCounterX(), ch.tm.offset);
}
/**
* @brief Stops a measurement and chains to the next one using the same time
* stamp.
*
* @param[in,out] tmp1 pointer to the @p time_measurement_t structure to be
* stopped
* @param[in,out] tmp2 pointer to the @p time_measurement_t structure to be
* started
*
*
* @xclass
*/
NOINLINE void chTMChainMeasurementToX(time_measurement_t *tmp1,
time_measurement_t *tmp2) {
/* Starts new measurement.*/
tmp2->last = chSysGetRealtimeCounterX();
/* Stops previous measurement using the same time stamp.*/
tm_stop(tmp1, tmp2->last, (rtcnt_t)0);
}
#endif /* CH_CFG_USE_TM == TRUE */
/** @} */