esp-idf/components/esp_system/esp_ipc.c
tgotic 23a290f29f esp_ipc: Use task notifications instead of semaphores
Closes https://github.com/espressif/esp-idf/pull/10226

- Drop the atomic usage
- Return the xSemaphoreTake for ask back
- Refactoring
2023-01-10 05:11:31 +08:00

202 lines
7.2 KiB
C

/*
* SPDX-FileCopyrightText: 2015-2022 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "esp_err.h"
#include "esp_ipc.h"
#include "esp_private/esp_ipc_isr.h"
#include "esp_attr.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/semphr.h"
#if !defined(CONFIG_FREERTOS_UNICORE) || defined(CONFIG_APPTRACE_GCOV_ENABLE)
#if CONFIG_COMPILER_OPTIMIZATION_NONE
#define IPC_STACK_SIZE (CONFIG_ESP_IPC_TASK_STACK_SIZE + 0x100)
#else
#define IPC_STACK_SIZE (CONFIG_ESP_IPC_TASK_STACK_SIZE)
#endif //CONFIG_COMPILER_OPTIMIZATION_NONE
static DRAM_ATTR StaticSemaphore_t s_ipc_mutex_buffer[portNUM_PROCESSORS];
static DRAM_ATTR StaticSemaphore_t s_ipc_ack_buffer[portNUM_PROCESSORS];
static TaskHandle_t s_ipc_task_handle[portNUM_PROCESSORS];
static SemaphoreHandle_t s_ipc_mutex[portNUM_PROCESSORS]; // This mutex is used as a global lock for esp_ipc_* APIs
static SemaphoreHandle_t s_ipc_ack[portNUM_PROCESSORS]; // Semaphore used to acknowledge that task was woken up,
static volatile esp_ipc_func_t s_func[portNUM_PROCESSORS] = { 0 }; // Function which should be called by high priority task
static void * volatile s_func_arg[portNUM_PROCESSORS]; // Argument to pass into s_func
typedef enum {
IPC_WAIT_NO = 0,
IPC_WAIT_FOR_START,
IPC_WAIT_FOR_END,
} esp_ipc_wait_t;
#if CONFIG_APPTRACE_GCOV_ENABLE
static volatile esp_ipc_func_t s_gcov_func = NULL; // Gcov dump starter function which should be called by high priority task
static void * volatile s_gcov_func_arg; // Argument to pass into s_gcov_func
#endif
static void IRAM_ATTR ipc_task(void* arg)
{
const int cpuid = (int) arg;
assert(cpuid == xPortGetCoreID());
#ifdef CONFIG_ESP_IPC_ISR_ENABLE
esp_ipc_isr_init();
#endif
while (true) {
uint32_t ipc_wait;
xTaskNotifyWait(0, ULONG_MAX, &ipc_wait, portMAX_DELAY);
#if CONFIG_APPTRACE_GCOV_ENABLE
if (s_gcov_func) {
(*s_gcov_func)(s_gcov_func_arg);
s_gcov_func = NULL;
/* we can not interfer with IPC calls so no need for further processing */
// esp_ipc API and gcov_from_isr APIs can be processed together if they came at the same time
if (ipc_wait == IPC_WAIT_NO) {
continue;
}
}
#endif // CONFIG_APPTRACE_GCOV_ENABLE
#ifndef CONFIG_FREERTOS_UNICORE
if (s_func[cpuid]) {
// we need to cache s_func, s_func_arg and ipc_ack variables locally
// because they can be changed by a subsequent IPC call (after xTaskNotify(caller_task_handle)).
esp_ipc_func_t func = s_func[cpuid];
s_func[cpuid] = NULL;
void* func_arg = s_func_arg[cpuid];
SemaphoreHandle_t ipc_ack = s_ipc_ack[cpuid];
if (ipc_wait == IPC_WAIT_FOR_START) {
xSemaphoreGive(ipc_ack);
(*func)(func_arg);
} else if (ipc_wait == IPC_WAIT_FOR_END) {
(*func)(func_arg);
xSemaphoreGive(ipc_ack);
} else {
abort();
}
}
#endif // !CONFIG_FREERTOS_UNICORE
}
// TODO: currently this is unreachable code. Introduce esp_ipc_uninit
// function which will signal to both tasks that they can shut down.
// Not critical at this point, we don't have a use case for stopping
// IPC yet.
// Also need to delete the semaphore here.
vTaskDelete(NULL);
}
/*
* Initialize inter-processor call module. This function is called automatically
* on CPU start and should not be called from the application.
*
* This function start two tasks, one on each CPU. These tasks are started
* with high priority. These tasks are normally inactive, waiting until one of
* the esp_ipc_call_* functions to be used. One of these tasks will be
* woken up to execute the callback provided to esp_ipc_call_nonblocking or
* esp_ipc_call_blocking.
*/
static void esp_ipc_init(void) __attribute__((constructor));
static void esp_ipc_init(void)
{
char task_name[] = "ipcX"; // up to 10 ipc tasks/cores (0-9)
for (int i = 0; i < portNUM_PROCESSORS; ++i) {
task_name[3] = i + (char)'0';
s_ipc_mutex[i] = xSemaphoreCreateMutexStatic(&s_ipc_mutex_buffer[i]);
s_ipc_ack[i] = xSemaphoreCreateBinaryStatic(&s_ipc_ack_buffer[i]);
portBASE_TYPE res = xTaskCreatePinnedToCore(ipc_task, task_name, IPC_STACK_SIZE, (void*) i,
configMAX_PRIORITIES - 1, &s_ipc_task_handle[i], i);
assert(res == pdTRUE);
(void)res;
}
}
static esp_err_t esp_ipc_call_and_wait(uint32_t cpu_id, esp_ipc_func_t func, void* arg, esp_ipc_wait_t wait_for)
{
if (cpu_id >= portNUM_PROCESSORS) {
return ESP_ERR_INVALID_ARG;
}
if (s_ipc_task_handle[cpu_id] == NULL) {
return ESP_ERR_INVALID_STATE;
}
if (xTaskGetSchedulerState() != taskSCHEDULER_RUNNING) {
return ESP_ERR_INVALID_STATE;
}
#ifdef CONFIG_ESP_IPC_USES_CALLERS_PRIORITY
TaskHandle_t task_handler = xTaskGetCurrentTaskHandle();
UBaseType_t priority_of_current_task = uxTaskPriorityGet(task_handler);
UBaseType_t priority_of_running_ipc_task = uxTaskPriorityGet(s_ipc_task_handle[cpu_id]);
if (priority_of_running_ipc_task < priority_of_current_task) {
vTaskPrioritySet(s_ipc_task_handle[cpu_id], priority_of_current_task);
}
xSemaphoreTake(s_ipc_mutex[cpu_id], portMAX_DELAY);
vTaskPrioritySet(s_ipc_task_handle[cpu_id], priority_of_current_task);
#else
xSemaphoreTake(s_ipc_mutex[0], portMAX_DELAY);
#endif
s_func[cpu_id] = func;
s_func_arg[cpu_id] = arg;
xTaskNotify(s_ipc_task_handle[cpu_id], wait_for, eSetValueWithOverwrite);
xSemaphoreTake(s_ipc_ack[cpu_id], portMAX_DELAY);
#ifdef CONFIG_ESP_IPC_USES_CALLERS_PRIORITY
xSemaphoreGive(s_ipc_mutex[cpu_id]);
#else
xSemaphoreGive(s_ipc_mutex[0]);
#endif
return ESP_OK;
}
esp_err_t esp_ipc_call(uint32_t cpu_id, esp_ipc_func_t func, void* arg)
{
return esp_ipc_call_and_wait(cpu_id, func, arg, IPC_WAIT_FOR_START);
}
esp_err_t esp_ipc_call_blocking(uint32_t cpu_id, esp_ipc_func_t func, void* arg)
{
return esp_ipc_call_and_wait(cpu_id, func, arg, IPC_WAIT_FOR_END);
}
// currently this is only called from gcov component
// the top level guarantees that the next call will be only after the previous one has completed
#if CONFIG_APPTRACE_GCOV_ENABLE
esp_err_t esp_ipc_start_gcov_from_isr(uint32_t cpu_id, esp_ipc_func_t func, void* arg)
{
if (xTaskGetSchedulerState() != taskSCHEDULER_RUNNING) {
return ESP_ERR_INVALID_STATE;
}
// Since it is called from an interrupt, it can not wait for a mutex to be released.
if (s_gcov_func == NULL) {
s_gcov_func_arg = arg;
s_gcov_func = func;
// If the target task already has a notification pending then its notification value is not updated (WithoutOverwrite).
xTaskNotifyFromISR(s_ipc_task_handle[cpu_id], IPC_WAIT_NO, eSetValueWithoutOverwrite, NULL);
return ESP_OK;
}
// the previous call was not completed
return ESP_FAIL;
}
#endif // CONFIG_APPTRACE_GCOV_ENABLE
#endif // !defined(CONFIG_FREERTOS_UNICORE) || defined(CONFIG_APPTRACE_GCOV_ENABLE)