72 lines
2.4 KiB
C++
72 lines
2.4 KiB
C++
/*
|
|
CoreMutex for the Raspberry Pi Pico RP2040
|
|
|
|
Implements a deadlock-safe multicore mutex for sharing things like the
|
|
USB or UARTs.
|
|
|
|
Copyright (c) 2021 Earle F. Philhower, III <earlephilhower@yahoo.com>
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
This library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include "Arduino.h"
|
|
#include "CoreMutex.h"
|
|
|
|
CoreMutex::CoreMutex(mutex_t *mutex, uint8_t option) {
|
|
_mutex = mutex;
|
|
_acquired = false;
|
|
_option = option;
|
|
_pxHigherPriorityTaskWoken = 0; // pdFALSE
|
|
if (__isFreeRTOS) {
|
|
auto m = __get_freertos_mutex_for_ptr(mutex);
|
|
|
|
if (__freertos_check_if_in_isr()) {
|
|
if (!__freertos_mutex_take_from_isr(m, &_pxHigherPriorityTaskWoken)) {
|
|
return;
|
|
}
|
|
// At this point we have the mutex in ISR
|
|
} else {
|
|
// Grab the mutex normally, possibly waking other tasks to get it
|
|
__freertos_mutex_take(m);
|
|
}
|
|
} else {
|
|
uint32_t owner;
|
|
if (!mutex_try_enter(_mutex, &owner)) {
|
|
if (owner == get_core_num()) { // Deadlock!
|
|
if (_option & DebugEnable) {
|
|
DEBUGCORE("CoreMutex - Deadlock detected!\n");
|
|
}
|
|
return;
|
|
}
|
|
mutex_enter_blocking(_mutex);
|
|
}
|
|
}
|
|
_acquired = true;
|
|
}
|
|
|
|
CoreMutex::~CoreMutex() {
|
|
if (_acquired) {
|
|
if (__isFreeRTOS) {
|
|
auto m = __get_freertos_mutex_for_ptr(_mutex);
|
|
if (__freertos_check_if_in_isr()) {
|
|
__freertos_mutex_give_from_isr(m, &_pxHigherPriorityTaskWoken);
|
|
} else {
|
|
__freertos_mutex_give(m);
|
|
}
|
|
} else {
|
|
mutex_exit(_mutex);
|
|
}
|
|
}
|
|
}
|