Quality RTOS & Embedded Software

 Real time embedded FreeRTOS RSS feed 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem


uxTaskGetStackHighWaterMark
[Task Control]

task. h
UBaseType_t uxTaskGetStackHighWaterMark ( TaskHandle_t xTask );

INCLUDE_uxTaskGetStackHighWaterMark must be defined as 1 for this function to be available. See the RTOS Configuration documentation for more information.

The stack used by a task will grow and shrink as the task executes and interrupts are processed. uxTaskGetStackHighWaterMark() returns the minimum amount of remaining stack space that was available to the task since the task started executing - that is the amount of stack that remained unused when the task stack was at its greatest (deepest) value. This is what is referred to as the stack 'high water mark'.

Parameters:
xTask The handle of the task being queried. A task may query its own high water mark by passing NULL as the xTask parameter.

Returns:
The value returned is the high water mark in words (for example, on a 32 bit machine a return value of 1 would indicate that 4 bytes of stack were unused). If the return value is zero then the task has likely overflowed its stack. If the return value is close to zero then the task has come close to overflowing its stack.
Example usage:

    void vTask1( void * pvParameters )
    {
    UBaseType_t uxHighWaterMark;

        /* Inspect our own high water mark on entering the task. */
        uxHighWaterMark = uxTaskGetStackHighWaterMark( NULL );

        for( ;; )
        {
            /* Call any function. */
            vTaskDelay( 1000 );

            /* Calling the function will have used some stack space, we would 
            therefore now expect uxTaskGetStackHighWaterMark() to return a 
            value lower than when it was called on entering the task. */
            uxHighWaterMark = uxTaskGetStackHighWaterMark( NULL );
        }
    }







[ Back to the top ]    [ About FreeRTOS ]    [ Privacy ]    [ Sitemap ]    [ ]


Copyright (C) Amazon Web Services, Inc. or its affiliates. All rights reserved.

Latest News

NXP tweet showing LPC5500 (ARMv8-M Cortex-M33) running FreeRTOS.

Version 10.1.1 of the FreeRTOS kernel is available for immediate download. MIT licensed.

View a recording of the "OTA Update Security and Reliability" webinar, presented by TI and AWS.


Careers

FreeRTOS and other embedded software careers at AWS.



FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Espressif ESP32

IAR Partner

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Renesas

STMicro RTOS partner supporting ARM7, ARM Cortex-M3, ARM Cortex-M4 and ARM Cortex-M0

Texas Instruments MCU Developer Network RTOS partner for ARM and MSP430 microcontrollers

OpenRTOS and SafeRTOS

Xilinx Microblaze and Zynq partner