| /* micro_int_to_task_evt.c - measure time from ISR to a rescheduled task */ |
| |
| /* |
| * Copyright (c) 2012-2014 Wind River Systems, Inc. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| /* |
| * DESCRIPTION |
| * This file contains test that measures time to switch from an interrupt |
| * handler to executing a task after rescheduling. In other words, execution |
| * after interrupt handler resume in a different task than the one which got |
| * interrupted. |
| */ |
| |
| #include <zephyr.h> |
| #include <irq_offload.h> |
| |
| #include "timestamp.h" |
| #include "utils.h" |
| |
| #include <arch/cpu.h> |
| |
| static uint32_t timestamp; |
| |
| /** |
| * |
| * @brief Test ISR used to measure best case interrupt latency |
| * |
| * The interrupt handler gets the second timestamp. |
| * |
| * @return N/A |
| */ |
| static void latencyTestIsr(void *unused) |
| { |
| ARG_UNUSED(unused); |
| |
| isr_event_send(EVENT0); |
| timestamp = TIME_STAMP_DELTA_GET(0); |
| } |
| |
| /** |
| * |
| * @brief Software interrupt generating task |
| * |
| * Lower priority task that, when starts, waits for a semaphore. When gets |
| * it, released by the main task, sets up the interrupt handler and generates |
| * the software interrupt |
| * |
| * @return 0 on success |
| */ |
| void microInt(void) |
| { |
| task_sem_take(INTSEMA, TICKS_UNLIMITED); |
| irq_offload(latencyTestIsr, NULL); |
| task_suspend(task_id_get()); |
| } |
| |
| /** |
| * |
| * @brief The test main function |
| * |
| * @return 0 on success |
| */ |
| int microIntToTaskEvt(void) |
| { |
| PRINT_FORMAT(" 2 - Measure time from ISR to executing a different task" |
| " (rescheduled)"); |
| TICK_SYNCH(); |
| task_sem_give(INTSEMA); |
| task_event_recv(EVENT0, TICKS_UNLIMITED); |
| timestamp = TIME_STAMP_DELTA_GET(timestamp); |
| PRINT_FORMAT(" switch time is %lu tcs = %lu nsec", |
| timestamp, SYS_CLOCK_HW_CYCLES_TO_NS(timestamp)); |
| return 0; |
| } |