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* [PATCH] emulator: inc/dec can have lock prefix
@ 2010-07-13 13:40 Gleb Natapov
  2010-07-13 13:54 ` Avi Kivity
  2010-07-14  0:09 ` Marcelo Tosatti
  0 siblings, 2 replies; 5+ messages in thread
From: Gleb Natapov @ 2010-07-13 13:40 UTC (permalink / raw)
  To: mtosatti, avi; +Cc: kvm

Mark inc (0xfe/0 0xff/0) and dec (0xfe/1 0xff/1) as lock prefix capable.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 255473f..b38bd8b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -345,10 +345,10 @@ static u32 group_table[] = {
 	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
 	0, 0, 0, 0,
 	[Group4*8] =
-	ByteOp | DstMem | SrcNone | ModRM, ByteOp | DstMem | SrcNone | ModRM,
+	ByteOp | DstMem | SrcNone | ModRM | Lock, ByteOp | DstMem | SrcNone | ModRM | Lock,
 	0, 0, 0, 0, 0, 0,
 	[Group5*8] =
-	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
+	DstMem | SrcNone | ModRM | Lock, DstMem | SrcNone | ModRM | Lock,
 	SrcMem | ModRM | Stack, 0,
 	SrcMem | ModRM | Stack, SrcMemFAddr | ModRM | ImplicitOps,
 	SrcMem | ModRM | Stack, 0,
--
			Gleb.

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH] emulator: inc/dec can have lock prefix
  2010-07-13 13:40 [PATCH] emulator: inc/dec can have lock prefix Gleb Natapov
@ 2010-07-13 13:54 ` Avi Kivity
  2010-07-13 13:58   ` Gleb Natapov
  2010-07-14  0:09 ` Marcelo Tosatti
  1 sibling, 1 reply; 5+ messages in thread
From: Avi Kivity @ 2010-07-13 13:54 UTC (permalink / raw)
  To: Gleb Natapov; +Cc: mtosatti, kvm

On 07/13/2010 04:40 PM, Gleb Natapov wrote:
> Mark inc (0xfe/0 0xff/0) and dec (0xfe/1 0xff/1) as lock prefix capable.
>
> Signed-off-by: Gleb Natapov<gleb@redhat.com>
> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> index 255473f..b38bd8b 100644
> --- a/arch/x86/kvm/emulate.c
> +++ b/arch/x86/kvm/emulate.c
> @@ -345,10 +345,10 @@ static u32 group_table[] = {
>   	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
>   	0, 0, 0, 0,
>   	[Group4*8] =
> -	ByteOp | DstMem | SrcNone | ModRM, ByteOp | DstMem | SrcNone | ModRM,
> +	ByteOp | DstMem | SrcNone | ModRM | Lock, ByteOp | DstMem | SrcNone | ModRM | Lock,
>   	0, 0, 0, 0, 0, 0,
>   	[Group5*8] =
> -	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
> +	DstMem | SrcNone | ModRM | Lock, DstMem | SrcNone | ModRM | Lock,
>   	SrcMem | ModRM | Stack, 0,
>   	SrcMem | ModRM | Stack, SrcMemFAddr | ModRM | ImplicitOps,
>   	SrcMem | ModRM | Stack, 0,
>    

Right.  Please post a regression test as well (kvm/test/x86/emulator.c).

Did this occur on a real workload?

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


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] emulator: inc/dec can have lock prefix
  2010-07-13 13:54 ` Avi Kivity
@ 2010-07-13 13:58   ` Gleb Natapov
  2010-07-13 16:52     ` Avi Kivity
  0 siblings, 1 reply; 5+ messages in thread
From: Gleb Natapov @ 2010-07-13 13:58 UTC (permalink / raw)
  To: Avi Kivity; +Cc: mtosatti, kvm

On Tue, Jul 13, 2010 at 04:54:01PM +0300, Avi Kivity wrote:
> On 07/13/2010 04:40 PM, Gleb Natapov wrote:
> >Mark inc (0xfe/0 0xff/0) and dec (0xfe/1 0xff/1) as lock prefix capable.
> >
> >Signed-off-by: Gleb Natapov<gleb@redhat.com>
> >diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> >index 255473f..b38bd8b 100644
> >--- a/arch/x86/kvm/emulate.c
> >+++ b/arch/x86/kvm/emulate.c
> >@@ -345,10 +345,10 @@ static u32 group_table[] = {
> >  	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
> >  	0, 0, 0, 0,
> >  	[Group4*8] =
> >-	ByteOp | DstMem | SrcNone | ModRM, ByteOp | DstMem | SrcNone | ModRM,
> >+	ByteOp | DstMem | SrcNone | ModRM | Lock, ByteOp | DstMem | SrcNone | ModRM | Lock,
> >  	0, 0, 0, 0, 0, 0,
> >  	[Group5*8] =
> >-	DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
> >+	DstMem | SrcNone | ModRM | Lock, DstMem | SrcNone | ModRM | Lock,
> >  	SrcMem | ModRM | Stack, 0,
> >  	SrcMem | ModRM | Stack, SrcMemFAddr | ModRM | ImplicitOps,
> >  	SrcMem | ModRM | Stack, 0,
> 
> Right.  Please post a regression test as well (kvm/test/x86/emulator.c).
> 
OK.

> Did this occur on a real workload?
> 
Yes, RHEL6 guest on RHEL6 host without ept.

--
			Gleb.

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] emulator: inc/dec can have lock prefix
  2010-07-13 13:58   ` Gleb Natapov
@ 2010-07-13 16:52     ` Avi Kivity
  0 siblings, 0 replies; 5+ messages in thread
From: Avi Kivity @ 2010-07-13 16:52 UTC (permalink / raw)
  To: Gleb Natapov; +Cc: mtosatti, kvm

On 07/13/2010 04:58 PM, Gleb Natapov wrote:
>
>> Did this occur on a real workload?
>>
>>      
> Yes, RHEL6 guest on RHEL6 host without ept.
>
>    

Ah, I wondered what load would use lock inc/dec on a pagetable or mmio, 
but that doesn't need to happen, all it takes is 'inc lock' on a 
recycled pagetable.

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


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] emulator: inc/dec can have lock prefix
  2010-07-13 13:40 [PATCH] emulator: inc/dec can have lock prefix Gleb Natapov
  2010-07-13 13:54 ` Avi Kivity
@ 2010-07-14  0:09 ` Marcelo Tosatti
  1 sibling, 0 replies; 5+ messages in thread
From: Marcelo Tosatti @ 2010-07-14  0:09 UTC (permalink / raw)
  To: Gleb Natapov; +Cc: avi, kvm

On Tue, Jul 13, 2010 at 04:40:23PM +0300, Gleb Natapov wrote:
> Mark inc (0xfe/0 0xff/0) and dec (0xfe/1 0xff/1) as lock prefix capable.
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>

Applied, thanks.


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2010-07-14  0:14 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-07-13 13:40 [PATCH] emulator: inc/dec can have lock prefix Gleb Natapov
2010-07-13 13:54 ` Avi Kivity
2010-07-13 13:58   ` Gleb Natapov
2010-07-13 16:52     ` Avi Kivity
2010-07-14  0:09 ` Marcelo Tosatti

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