Quality RTOS & Embedded Software

 Real time embedded FreeRTOS RSS feed 
Real time embedded FreeRTOS mailing list 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem TCP & FAT Training


Help with configASSERT in vPortExitCritical

Posted by booherbg on April 13, 2017

Hi all. I have an intermittant bug that I'm trying to track down. Essentially an assertion failure in line 413 of port.c -- basically the first line of vPortExitCritical():

~~~ void vPortExitCritical( void ) { configASSERT( uxCriticalNesting ); uxCriticalNesting--; if( uxCriticalNesting == 0 ) { portENABLE_INTERRUPTS(); } } ~~~

I am trying to get my debugger to get trapped here so I can see a call trace. Even with a trace I fear that the actual reason for the error would be a previous call to vPortExitCritical(), as the assertion is simply that uxCriticalNesting is actually 0.

I would love any tips on where to look for how to track this down. I suspect there may be an issue with priorities, or some rogue conditional branch that may be causing this. It feels like someone is calling vPortExitCritical() from outside a critical region (thus reducing uxCriticalNesting to 0 prematurely). Does that sound like a correct guess?

I'm running FreeRTOS 8.2.3 on an Arm Cortex M7, and a Segger J-LINK debugger.


Help with configASSERT in vPortExitCritical

Posted by rtel on April 13, 2017

You can add some code to give yourself a place to place a break point, as follows:

void vPortExitCritical( void )
     if( uxCriticalNesting == 0 )
         __asm volatile ( "NOP" );

     // Rest of vPortExitCritical() code goes here.

This uses GCC syntax. You can then place your breakpoint on the NOP instruction.

Help with configASSERT in vPortExitCritical

Posted by booherbg on April 13, 2017

Thank you. I'm giving this a try to see what my call trace looks like.

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

Copyright (C) 2004-2010 Richard Barry. Copyright (C) 2010-2016 Real Time Engineers Ltd.
Any and all data, files, source code, html content and documentation included in the FreeRTOSTM distribution or available on this site are the exclusive property of Real Time Engineers Ltd.. See the files license.txt (included in the distribution) and this copyright notice for more information. FreeRTOSTM and FreeRTOS.orgTM are trade marks of Real Time Engineers Ltd.

Latest News:

FreeRTOS V9.0.0 is now available for download.

Free TCP/IP and file system demos for the RTOS

Sponsored Links

⇓ Now With No Code Size Limit! ⇓
⇑ Free Download Without Registering ⇑

FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Renesas Electronics Gold Alliance RTOS Partner.jpg

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Atmel RTOS partner supporting ARM Cortex-M3 and AVR32 microcontrollers

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

Xilinx Microblaze and Zynq partner

Silicon Labs low power RTOS partner

Altera RTOS partner for Nios II and Cortex-A9 SoC

Freescale Alliance RTOS Member supporting ARM and ColdFire microcontrollers

Infineon ARM Cortex-M microcontrollers

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

Cypress RTOS partner supporting ARM Cortex-M3

Fujitsu RTOS partner supporting ARM Cortex-M3 and FM3

Microsemi (previously Actel) RTOS partner supporting ARM Cortex-M3

Atollic Partner

IAR Partner

Keil ARM Partner

Embedded Artists