NRF_LOG is not thread safe

[Dave_couling]

I'm developing in a freeRTOS environment. One thread is sampling the ADC using PPI at 200Hz, which various other threads sample Sensors via SPI and finally I'm using the NRF_LOG thread example from the freertos example.  I've noticed however when I enable logging (either RTT or UART),  the debugger crashes and it seems the FW restarts.  If I disable Logging I don't see any issues.  These leads me to believe that NRF_LOG is in fact not thread safe, even when deferred logs are enabled.  This is especially noticeable when I run the BLE thread.  

[Dave_couling]

I can trigger this faster if I try a stress test by running the through-put test.  Basically what happens is the System Resets (even though debug flags are enabled).  The Debugger goes crazy and spits out the following

[Edvin]

Have you checked whether you are receiving an app_error?

How do you use the log module? I assume you log from multiple threads in FreeRTOS? Do you call NRF_LOG_PROCESS() from different instances as well? Does the issue happen if you only do logging from one thread?

BR,

Edvin

[Dave_couling]

This ended up being a hardware issue.  My nRF52832 was corrupted somehow.  When enabling ADC, SPI and UART, the chip drew 87mA on the PCA10040 board.  Even if I had nothing connected on those data ports I still saw 85mA draw.  When I started streaming data over BLE as well, the increase in current pulled down the voltage rail causing the debugger to lose connection to the target.  I soldered on a new IC and it works perfectly.