Re: [Xen-devel] [PATCH] svm: Do not intercept RDTCS(P) when TSC scaling is supported by hardware

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 25.04.12 at 17:01, Dan Magenheimer <dan.magenheimer@xxxxxxxxxx> wrote:
>>  From: Jan Beulich [mailto:JBeulich@xxxxxxxx]
>> Sent: Wednesday, April 25, 2012 3:27 AM
>> To: Boris Ostrovsky; Dan Magenheimer
>> Cc: wei.huang2@xxxxxxx; xen-devel; keir@xxxxxxx 
>> Subject: Re: [PATCH] svm: Do not intercept RDTCS(P) when TSC scaling is 
> supported by hardware
>> 
>> >>> On 20.04.12 at 04:21, Boris Ostrovsky <boris.ostrovsky@xxxxxxx> wrote:
>> > # HG changeset patch
>> > # User Boris Ostrovsky <boris.ostrovsky@xxxxxxx>
>> > # Date 1334875170 14400
>> > # Node ID 55bf11ebce87ceb73fb2c372dcef170ec0bb4a18
>> > # Parent  7c777cb8f705411b77c551f34ba88bdc09e38ab8
>> > svm: Do not intercept RDTCS(P) when TSC scaling is supported by hardware
>> >
>> > When running in TSC_MODE_ALWAYS_EMULATE mode on processors that support
>> > TSC scaling we don't need to intercept RDTSC/RDTSCP instructions.
>> >
>> > Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxx>
>> > Acked-by: Wei Huang <wei.huang2@xxxxxxx>
>> > Tested-by: Wei Huang <wei.huang2@xxxxxxx>
>> 
>> So what's the status of the discussion around this patch? Were
>> your concerns all addressed, Dan? Is there any re-submisson
>> necessary/planned?
> 
> My concerns will be addressed when there is a fully-functional
> adequately-tested full-stack implementation, rather than "we
> have a new instruction that should solve (part of) this problem,
> let's turn it on by default."
> 
> While I wish I could invest the time required to do (or
> participate in) the testing, sadly I can't, so I understand
> if my opinion is discarded.

As Keir had asked to get an ACK/NAK from you - is this then a NAK
or a "don't care" or yet something else (it doesn't read anywhere
close to an ACK in any case).

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel