Re: [PATCH v4 13/17] watchdog/hardlockup: detect hard lockups using secondary (buddy) CPUs

On Fri May 5, 2023 at 8:13 AM AEST, Douglas Anderson wrote:

From: Colin Cross <redacted>

Implement a hardlockup detector that doesn't doesn't need any extra
arch-specific support code to detect lockups. Instead of using
something arch-specific we will use the buddy system, where each CPU
watches out for another one. Specifically, each CPU will use its
softlockup hrtimer to check that the next CPU is processing hrtimer
interrupts by verifying that a counter is increasing.

Powerpc's watchdog has an SMP checker, did you see it? It's all to
all rather than buddy which makes it more complicated but arguably
bit better functionality.

Thanks,
Nick