Subject: Re: [PATCH 1/3] kernel/sched: introduce vcpu preempted check interface

From: xinhui <[email-masked]>
Date: Tue, 28 Jun 2016 11:14:56 +0800

On 2016年06月27日 22:02, Peter Zijlstra wrote:
> On Mon, Jun 27, 2016 at 04:00:43PM +0200, Peter Zijlstra wrote:
>> On Mon, Jun 27, 2016 at 01:41:28PM -0400, Pan Xinhui wrote:
>>> +++ b/include/linux/sched.h
>>> @@ -3293,6 +3293,15 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
>>>
>>>   #endif /* CONFIG_SMP */
>>>
>>> +#ifdef arch_vcpu_is_preempted
>>> +static inline bool vcpu_is_preempted(int cpu)
>>> +{
>>> +	return arch_vcpu_is_preempted(cpu);
>>> +}
>>> +#else
>>> +#define vcpu_is_preempted(cpu)	false
>>> +#endif
>>
>> #ifndef vcpu_is_preempted
>> #define vcpu_is_preempted(cpu)		(false)
>> #endif
>>
>> Is so much simpler...
>>
fair enough.

>> Also, please Cc the virt list so that other interested parties can
>> comment, and maybe also the s390 folks.
>
oh. I forgot that. maybe we need cc more.

root@ltcalpine2-lp13:~/linux# find ./arch -name kvm
./arch/arm/kvm
./arch/arm64/kvm
./arch/mips/kvm
./arch/powerpc/kvm
./arch/s390/kvm
./arch/tile/kvm
./arch/x86/kvm

> And before you hurry off to post again, add a patch doing
> mutex_spin_on_owner() and rwsem_spin_in_owner().
>
will do that.

thanks for your suggestion. :)