Re: [kvm-unit-tests PATCH v3 5/9] s390x: smp: Wait for cpu setup to finish

David Hildenbrand
2020-01-20T12:07:16Z

On 17.01.20 11:46, Janosch Frank wrote:
> We store the user provided psw address into restart new, so a psw
> restart does not lead us through setup again.
>
> Also we wait on smp_cpu_setup() until the cpu has finished setup
> before returning. This is necessary for z/VM and LPAR where sigp is
> asynchronous.
>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Reviewed-by: David Hildenbrand <david@redhat.com>
> ---
> lib/s390x/smp.c | 2 ++
> s390x/cstart64.S | 2 ++
> 2 files changed, 4 insertions(+)
>
> diff --git a/lib/s390x/smp.c b/lib/s390x/smp.c
> index 84e681d..9dad146 100644
> --- a/lib/s390x/smp.c
> +++ b/lib/s390x/smp.c
> @@ -204,6 +204,8 @@ int smp_cpu_setup(uint16_t addr, struct psw psw)
>
> /* Start processing */
> smp_cpu_restart_nolock(addr, NULL);
> + /* Wait until the cpu has finished setup and started the provided psw */
> + while (lc->restart_new_psw.addr != psw.addr) { mb(); }

while (lc->restart_new_psw.addr != psw.addr)
mb();

--
Thanks,

David / dhildenb