zephyr/kernel/nanokernel/profiler.c

148 lines
4.1 KiB
C

/*
* Copyright (c) 2015 Intel Corporation
*
* Licensed 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.
*/
/*
* @file
* @brief Profiler support.
*/
#include <misc/profiler.h>
#include <misc/util.h>
#include <init.h>
#include <nano_private.h>
#include <profiler_arch.h>
uint32_t _sys_profiler_buffer[CONFIG_PROFILER_BUFFER_SIZE];
#ifdef CONFIG_PROFILER_CONTEXT_SWITCH
void *_collector_fiber = NULL;
#endif
#ifdef CONFIG_PROFILER_SLEEP
uint32_t _sys_profiler_sleep_start_time;
#endif
/**
* @brief Initialize the profiler system.
*
* @details Initialize the ring buffer and the sync semaphore.
*
* @return No return value.
*/
static int _sys_profiler_init(struct device *arg)
{
ARG_UNUSED(arg);
sys_event_logger_init(&sys_profiler_logger, _sys_profiler_buffer,
CONFIG_PROFILER_BUFFER_SIZE);
return 0;
}
DECLARE_DEVICE_INIT_CONFIG(profiler_0, "", _sys_profiler_init, NULL);
nano_early_init(profiler_0, NULL);
void sys_profiler_put_timed(uint16_t event_id)
{
uint32_t data[1];
data[0] = nano_tick_get_32();
sys_event_logger_put(&sys_profiler_logger, event_id, data,
ARRAY_SIZE(data));
}
#ifdef CONFIG_PROFILER_CONTEXT_SWITCH
void _sys_profiler_context_switch(void)
{
extern tNANO _nanokernel;
uint32_t data[2];
extern void _sys_event_logger_put_non_preemptible(
struct event_logger *logger, uint16_t event_id, uint32_t *event_data,
uint8_t data_size);
/* if the profiler has not been initialized, we do nothing */
if (sys_profiler_logger.ring_buf.buf == NULL) {
return;
}
if (_collector_fiber != _nanokernel.current) {
data[0] = nano_tick_get_32();
data[1] = (uint32_t)_nanokernel.current;
/*
* The mechanism we use to log the profile events uses a sync semaphore
* to inform that there are available events to be collected. The
* context switch event can be triggered from a task. When we
* signal a semaphore from a task and a fiber is waiting for
* that semaphore, a context switch is generated immediately. Due to
* the fact that we register the context switch event while the context
* switch is being processed, a new context switch can be generated
* before the kernel finishes processing the current context switch. We
* need to prevent this because the kernel is not able to handle it.
* The _sem_give_non_preemptible function does not trigger a context
* switch when we signal the semaphore from any type of thread. Using
* _sys_event_logger_put_non_preemptible function, that internally uses
* _sem_give_non_preemptible function for signaling the sync semaphore,
* allow us registering the context switch event without triggering any
* new context switch during the process.
*/
_sys_event_logger_put_non_preemptible(&sys_profiler_logger,
PROFILER_CONTEXT_SWITCH_EVENT_ID, data, ARRAY_SIZE(data));
}
}
void sys_profiler_register_as_collector(void)
{
_collector_fiber = _nanokernel.current;
}
#endif /* CONFIG_PROFILER_CONTEXT_SWITCH */
#ifdef CONFIG_PROFILER_INTERRUPT
void _sys_profiler_interrupt(void)
{
uint32_t data[2];
data[0] = nano_tick_get_32();
data[1] = _sys_current_irq_key_get();
sys_profiler_put(PROFILER_INTERRUPT_EVENT_ID, data, ARRAY_SIZE(data));
}
#endif /* CONFIG_PROFILER_INTERRUPT */
#ifdef CONFIG_PROFILER_SLEEP
void _sys_profiler_enter_sleep(void)
{
_sys_profiler_sleep_start_time = nano_cycle_get_32();
}
void _sys_profiler_exit_sleep(void)
{
uint32_t data[3];
data[0] = nano_tick_get_32();
data[1] = (nano_cycle_get_32() - _sys_profiler_sleep_start_time) / sys_clock_hw_cycles_per_tick;
/* register the cause of exiting sleep mode */
data[2] = _sys_current_irq_key_get();
sys_profiler_put(PROFILER_SLEEP_EVENT_ID, data, ARRAY_SIZE(data));
}
#endif /* CONFIG_PROFILER_SLEEP */