Re: [PATCH 2/5] stop_machine: yield CPU during stop machine

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 21/10/16 14:05, Peter Zijlstra wrote:
> On Fri, Oct 21, 2016 at 01:58:55PM +0200, Christian Borntraeger wrote:
>> stop_machine can take a very long time if the hypervisor does
>> overcommitment for guest CPUs. When waiting for "the one", lets
>> give up our CPU by using the new cpu_relax_yield.
> 
> This seems something that would apply to most other virt stuff. Lets Cc
> a few more lists for that.

Corrected xen-devel mail address.


Juergen

> 
>> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
>> ---
>>  kernel/stop_machine.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
>> index ec9ab2f..1eb8266 100644
>> --- a/kernel/stop_machine.c
>> +++ b/kernel/stop_machine.c
>> @@ -194,7 +194,7 @@ static int multi_cpu_stop(void *data)
>>  	/* Simple state machine */
>>  	do {
>>  		/* Chill out and ensure we re-read multi_stop_state. */
>> -		cpu_relax();
>> +		cpu_relax_yield();
>>  		if (msdata->state != curstate) {
>>  			curstate = msdata->state;
>>  			switch (curstate) {
>> -- 
>> 2.5.5
>>
> _______________________________________________
> Virtualization mailing list
> Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
> https://lists.linuxfoundation.org/mailman/listinfo/virtualization
> 

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux