Re: [PATCH kvm-unit-tests v1 1/6] lib: s390x: smp: Retry SIGP SENSE on CC2

Nico Boehr
2022-03-07T11:50:19Z

On Thu, 2022-03-03 at 22:04 +0100, Eric Farman wrote:
> The routine smp_cpu_stopped() issues a SIGP SENSE, and returns true
> if it received a CC1 (STATUS STORED) with the STOPPED or CHECK STOP
> bits enabled. Otherwise, it returns false.
>
> This is misleading, because a CC2 (BUSY) merely indicates that the
> order code could not be processed, not that the CPU is operating.
> It could be operating but in the process of being stopped.
>
> Convert the invocation of the SIGP SENSE to retry when a CC2 is
> received, so we get a more definitive answer.
>
> Signed-off-by: Eric Farman <farman@linux.ibm.com>

Reviewed-by: Nico Boehr <nrb@linux.ibm.com>