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* Updating dirty bitmap by non-atomic set bit is safe?
@ 2010-03-23  6:12 Takuya Yoshikawa
  2010-03-23  9:18 ` Avi Kivity
  0 siblings, 1 reply; 3+ messages in thread
From: Takuya Yoshikawa @ 2010-03-23  6:12 UTC (permalink / raw)
  To: KVM list

Hi, does anybody knows about this?


Currently, dirty bitmap is updated by generic___set_le_bit().
I checked the git log and mail archives but could not find any
explanation why replacing set_bit() by generic___set_le_bit() is
safe.


Thanks,
  Takuya

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Updating dirty bitmap by non-atomic set bit is safe?
  2010-03-23  6:12 Updating dirty bitmap by non-atomic set bit is safe? Takuya Yoshikawa
@ 2010-03-23  9:18 ` Avi Kivity
  2010-03-23 10:17   ` Takuya Yoshikawa
  0 siblings, 1 reply; 3+ messages in thread
From: Avi Kivity @ 2010-03-23  9:18 UTC (permalink / raw)
  To: Takuya Yoshikawa; +Cc: KVM list

On 03/23/2010 08:12 AM, Takuya Yoshikawa wrote:
> Hi, does anybody knows about this?
>
>
> Currently, dirty bitmap is updated by generic___set_le_bit().
> I checked the git log and mail archives but could not find any
> explanation why replacing set_bit() by generic___set_le_bit() is
> safe.
>   

IIRC it's protected by the mmu spinlock.

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


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Updating dirty bitmap by non-atomic set bit is safe?
  2010-03-23  9:18 ` Avi Kivity
@ 2010-03-23 10:17   ` Takuya Yoshikawa
  0 siblings, 0 replies; 3+ messages in thread
From: Takuya Yoshikawa @ 2010-03-23 10:17 UTC (permalink / raw)
  To: Avi Kivity; +Cc: KVM list

Avi Kivity wrote:
> On 03/23/2010 08:12 AM, Takuya Yoshikawa wrote:
>> Hi, does anybody knows about this?
>>
>>
>> Currently, dirty bitmap is updated by generic___set_le_bit().
>> I checked the git log and mail archives but could not find any
>> explanation why replacing set_bit() by generic___set_le_bit() is
>> safe.
>>   
> 
> IIRC it's protected by the mmu spinlock.
> 

So the fact is the old version did extra protection, thank you.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2010-03-23 10:14 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2010-03-23  6:12 Updating dirty bitmap by non-atomic set bit is safe? Takuya Yoshikawa
2010-03-23  9:18 ` Avi Kivity
2010-03-23 10:17   ` Takuya Yoshikawa

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