Re: [PATCH v2 1/1] s390/spinlock: Provide vcpu_is_preempted

On Wed, Oct 19, 2016 at 08:56:36AM +0200, Christian Borntraeger wrote:

On 09/29/2016 05:51 PM, Christian Borntraeger wrote:

quoted

this implements the s390 backend for commit
"kernel/sched: introduce vcpu preempted check interface"
by reworking the existing smp_vcpu_scheduled into
arch_vcpu_is_preempted. We can then also get rid of the
local cpu_is_preempted function by moving the
CIF_ENABLED_WAIT test into arch_vcpu_is_preempted.

Signed-off-by: Christian Borntraeger <redacted>

Martin, Peter,

I think we could go with the patch as is. In other words not providing
arch_vcpu_is_preempted for !CONFIG_SMP.

This will result in compile errors if code does spinning or yielding for
non-SMP kernels - which does not make sense to me, so this might actually
be a nice indicator.
If you prefer the !CONFIG_SMP implementation let me know and I will respin.

...but I do prefer an implementation for !CONFIG_SMP. I'm tired of fixing
silly compile errors that only happen on s390.