Interrupt priority issues with fstorage and FreeRTOS

[TS Gowtham]

Hi,

I'm using an nRF52832 with SDK 14.2 and FreeRTOS. I'm hitting a configASSERT when I call nrf_fstorage_erase. I called the function after calling ble_stack_init but before calling nrf_sdh_freertos_init. 

I hit the asssert at SWI2_EGU2_IRQHandler (SD_EVT_IRQHandler, nrf_sdh_freertos.c, line 65) which called vTaskNotifyGiveFromISR (tasks.c, line 4309). From what I understood in the comment block in this function, the assert seems to be due to an issue with the interrupt priority. But I couldn't find an configs for the interrupt priority of fstorage.

Next, I tried calling the fstorage function from another task. This time, I didn't hit the assert, but there didn't seem to be any changes in the flash registers when I did a memory dump.

Can someone please help me get the root cause for this issue?

Also, I had read a post mentioning that FDS is not thread safe and this link also says that the backends are not thread safe. Is fstorage also not thread safe? 

Thanks,

Gowtham

[Susheel Nuguru]

Did you get the event complete event for fds after you do a page erase?

If not there might be some priority issues with your task. 

[TS Gowtham]

I just tried suspending two tasks which were of high priority and were taking up a majority percentage of processing time. This time the flash R/W operations were successful. But this still from a task and not from the main function.

[Susheel Nuguru]

For me it seems the issue is with architecting the priorities and yielding of the tasks in your app