circuitpython/supervisor/shared/background_callback.c
Jeff Epler 36b4646516 background_callback: Avoid CALLBACK_CRITICAL_BEGIN with nothing to do
CALLBACK_CRITICAL_BEGIN is heavyweight, but we can be confident we do
not have work to do as long as callback_head is NULL.

This gives back performance on nRF.
2020-07-15 09:26:47 -05:00

108 lines
3.4 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2020 Jeff Epler for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "py/mpconfig.h"
#include "supervisor/background_callback.h"
#include "supervisor/shared/tick.h"
#include "shared-bindings/microcontroller/__init__.h"
STATIC volatile background_callback_t *callback_head, *callback_tail;
#define CALLBACK_CRITICAL_BEGIN (common_hal_mcu_disable_interrupts())
#define CALLBACK_CRITICAL_END (common_hal_mcu_enable_interrupts())
void background_callback_add_core(background_callback_t *cb) {
CALLBACK_CRITICAL_BEGIN;
if (cb->prev || callback_head == cb) {
CALLBACK_CRITICAL_END;
return;
}
cb->next = 0;
cb->prev = (background_callback_t*)callback_tail;
if (callback_tail) {
callback_tail->next = cb;
cb->prev = (background_callback_t*)callback_tail;
}
if (!callback_head) {
callback_head = cb;
}
callback_tail = cb;
CALLBACK_CRITICAL_END;
}
void background_callback_add(background_callback_t *cb, background_callback_fun fun, void *data) {
cb->fun = fun;
cb->data = data;
background_callback_add_core(cb);
}
static bool in_background_callback;
void background_callback_run_all() {
if (!callback_head) {
return;
}
CALLBACK_CRITICAL_BEGIN;
if (in_background_callback) {
CALLBACK_CRITICAL_END;
return;
}
in_background_callback = true;
background_callback_t *cb = (background_callback_t*)callback_head;
callback_head = NULL;
callback_tail = NULL;
while (cb) {
background_callback_t *next = cb->next;
cb->next = cb->prev = NULL;
background_callback_fun fun = cb->fun;
void *data = cb->data;
CALLBACK_CRITICAL_END;
// Leave the critical section in order to run the callback function
if (fun) {
fun(data);
}
CALLBACK_CRITICAL_BEGIN;
cb = next;
}
in_background_callback = false;
CALLBACK_CRITICAL_END;
}
void background_callback_begin_critical_section() {
CALLBACK_CRITICAL_BEGIN;
}
void background_callback_end_critical_section() {
CALLBACK_CRITICAL_END;
}
void background_callback_reset() {
CALLBACK_CRITICAL_BEGIN;
callback_head = NULL;
callback_tail = NULL;
in_background_callback = false;
CALLBACK_CRITICAL_END;
}