Re: [PATCH][RFC] kvm-scheduler integration

[Avi Kivity <avi@qumranet.com>]

Ingo Molnar wrote:
> * Avi Kivity <avi@qumranet.com> wrote:
>
>   
>> +#ifdef CONFIG_SCHED_KVM
>> +static __read_mostly struct sched_kvm_hooks kvm_hooks;
>> +#endif
>>     
>
> please just add a current->put_vcpu() function pointer instead of this 
> hooks thing.
>
>   

Won't that increase task_struct (16 bytes on 64-bit) unnecessarily?  The 
function pointers are common to all virtual machines.

>>  static inline void prepare_task_switch(struct rq *rq, struct task_struct *next)
>>  {
>> +	unload_kvm_vcpu(current);
>>  	prepare_lock_switch(rq, next);
>>  	prepare_arch_switch(next);
>>  }
>> @@ -1860,6 +1912,7 @@ static inline void finish_task_switch(struct rq *rq, struct task_struct *prev)
>>  	prev_state = prev->state;
>>  	finish_arch_switch(prev);
>>  	finish_lock_switch(rq, prev);
>> +	reload_kvm_vcpu(current);
>>     
>
> ok, this looks certainly cheap enough from a scheduler POV, and it 
> cleans up the whole KVM/scheduling interaction quite nicely. (I'd not 
> bother with tweaking the migration logic, there's enough incentive for 
> the scheduler to keep tasks from migrating unnecessarily.)
>   

Okay.

-- 
error compiling committee.c: too many arguments to function