Re: madvise() not triggering page discard with MMU-notifiers

[Anthony Liguori <aliguori@us.ibm.com>]

Andrea Arcangeli wrote:
> On Mon, Aug 18, 2008 at 05:04:25PM -0500, Anthony Liguori wrote:
>   
>> +    if (!kvm_enabled() || !qemu_kvm_has_mmu_notifiers())
>> +        madvise(addr, TARGET_PAGE_SIZE,
>> +                deflate ? MADV_WILLNEED : MADV_DONTNEED);
>>     
>
> The check was reversed so madvise wasn't invoked in the first place if
> mmu notifier was enabled in the host kernel. This should fix it
> (untested):
>
>        if (!kvm_enabled() || kvm_has_sync_mmu())
>   

Ugh, sorry about that Andrea.

I've sent out an updated patch set.  With MMU notifiers, ballooning is 
working exactly as expected.

Regards,

Anthony Liguori