Forum Discussion
yepp
New Contributor
New ContributorLinux UIO IRQ related periodic CPU usage
Hi, I have an Intel Arria 10 SoC FPGA system with 5.4.104-lts Linux built with Yocto 3.3.1 and Poky. The installed FPGA image is doing nothing more than making interrupts to an UIO device, ...
TiensungA_Altera
Occasional Contributor
Occasional ContributorWe have tried several experiments, and it seems it is unrelated to the interrupt storm.
If you have ran out of ideas, my only last resort is not use UIO and write a simple Kernel driver that maps to the IRQ. Just creates a simple handler ISR to dump out the number of interrupts per minute in printf. Every time, you receive an interrupt, you increase a counter. You poll this counter and you do a printf every 1-2minutes so, you don't clutter your log terminal.
By bypassing UIO, we can definitely check isolate where the problem is?
If there are no CPU spikes by doing so, then, the UIO is a suspect.
To me, this would be the simplest way to find out which component causes the problem.
