Xen devel - May 2013 - [PATCH 0/2] runstate_memory_area on ARM

Hi all,
this patch series introduces support for runstate_memory_area on ARM.
The first patch moves VCPUOP_register_runstate_memory_area to common
code, while the second one add VCPUOP_register_runstate_memory_area to
the whilelist of vcpu_op hypercalls supported on ARM and properly
updates the runstate_memory_area during vcpu context switch.


Stefano Stabellini (2):
      xen: move VCPUOP_register_runstate_memory_area to common code
      xen/arm: handle the runstate_memory_area

 xen/arch/arm/domain.c |   22 ++++++++++++++++------
 xen/arch/x86/domain.c |   28 ----------------------------
 xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 34 deletions(-)


Cheers,

Stefano

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/x86/domain.c |   28 ----------------------------
 xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index d1b6c64..87dcb73 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -960,34 +960,6 @@ arch_do_vcpu_op(
 
     switch ( cmd )
     {
-    case VCPUOP_register_runstate_memory_area:
-    {
-        struct vcpu_register_runstate_memory_area area;
-        struct vcpu_runstate_info runstate;
-
-        rc = -EFAULT;
-        if ( copy_from_guest(&area, arg, 1) )
-            break;
-
-        if ( !guest_handle_okay(area.addr.h, 1) )
-            break;
-
-        rc = 0;
-        runstate_guest(v) = area.addr.h;
-
-        if ( v == current )
-        {
-            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
-        }
-        else
-        {
-            vcpu_runstate_get(v, &runstate);
-            __copy_to_guest(runstate_guest(v), &runstate, 1);
-        }
-
-        break;
-    }
-
     /*
      * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to the given
      * virtual address even when running in another domain''s address
space.
diff --git a/xen/common/domain.c b/xen/common/domain.c
index d21909f..0752dd2 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -1126,6 +1126,34 @@ long do_vcpu_op(int cmd, int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
         break;
     }
 
+    case VCPUOP_register_runstate_memory_area:
+    {
+        struct vcpu_register_runstate_memory_area area;
+        struct vcpu_runstate_info runstate;
+
+        rc = -EFAULT;
+        if ( copy_from_guest(&area, arg, 1) )
+            break;
+
+        if ( !guest_handle_okay(area.addr.h, 1) )
+            break;
+
+        rc = 0;
+        runstate_guest(v) = area.addr.h;
+
+        if ( v == current )
+        {
+            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
+        }
+        else
+        {
+            vcpu_runstate_get(v, &runstate);
+            __copy_to_guest(runstate_guest(v), &runstate, 1);
+        }
+
+        break;
+    }
+
 #ifdef VCPU_TRAP_NMI
     case VCPUOP_send_nmi:
         if ( !guest_handle_is_null(arg) )
-- 
1.7.2.5

Support VCPUOP_register_runstate_memory_area on ARM.
Update_runstate_area on context switch.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/domain.c |   22 ++++++++++++++++------
 1 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 2d018cf..40bf963 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -22,6 +22,7 @@
 
 #include <asm/current.h>
 #include <asm/event.h>
+#include <asm/guest_access.h>
 #include <asm/regs.h>
 #include <asm/p2m.h>
 #include <asm/irq.h>
@@ -212,16 +213,25 @@ static void ctxt_switch_to(struct vcpu *n)
     virt_timer_restore(n);
 }
 
+/* Update per-VCPU guest runstate shared memory area (if registered). */
+static void update_runstate_area(struct vcpu *v)
+{
+    if ( guest_handle_is_null(runstate_guest(v)) )
+        return;
+
+    __copy_to_guest(runstate_guest(v), &v->runstate, 1);
+}
+
 static void schedule_tail(struct vcpu *prev)
 {
     ctxt_switch_from(prev);
 
     local_irq_enable();
 
-    /* TODO
-       update_runstate_area(current);
-    */
     ctxt_switch_to(current);
+
+    if ( prev != current )
+        update_runstate_area(current);
 }
 
 static void continue_new_vcpu(struct vcpu *prev)
@@ -241,9 +251,8 @@ void context_switch(struct vcpu *prev, struct vcpu *next)
     ASSERT(prev != next);
     ASSERT(cpumask_empty(next->vcpu_dirty_cpumask));
 
-    /* TODO
-       update_runstate_area(prev);
-    */
+    if ( prev != next )
+        update_runstate_area(prev);
 
     local_irq_disable();
 
@@ -636,6 +645,7 @@ long do_arm_vcpu_op(int cmd, int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
     switch ( cmd )
     {
         case VCPUOP_register_vcpu_info:
+        case VCPUOP_register_runstate_memory_area:
             return do_vcpu_op(cmd, vcpuid, arg);
         default:
             return -EINVAL;
-- 
1.7.2.5

On Wed, 2013-05-01 at 20:32 +0100, Stefano Stabellini
wrote:
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Needs x86 and/or core acks, but lacks suitable CCs. Added.
> ---
>  xen/arch/x86/domain.c |   28 ----------------------------
>  xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
>  2 files changed, 28 insertions(+), 28 deletions(-)
> 
> diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
> index d1b6c64..87dcb73 100644
> --- a/xen/arch/x86/domain.c
> +++ b/xen/arch/x86/domain.c
> @@ -960,34 +960,6 @@ arch_do_vcpu_op(
>  
>      switch ( cmd )
>      {
> -    case VCPUOP_register_runstate_memory_area:
> -    {
> -        struct vcpu_register_runstate_memory_area area;
> -        struct vcpu_runstate_info runstate;
> -
> -        rc = -EFAULT;
> -        if ( copy_from_guest(&area, arg, 1) )
> -            break;
> -
> -        if ( !guest_handle_okay(area.addr.h, 1) )
> -            break;
> -
> -        rc = 0;
> -        runstate_guest(v) = area.addr.h;
> -
> -        if ( v == current )
> -        {
> -            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
> -        }
> -        else
> -        {
> -            vcpu_runstate_get(v, &runstate);
> -            __copy_to_guest(runstate_guest(v), &runstate, 1);
> -        }
> -
> -        break;
> -    }
> -
>      /*
>       * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to the
given
>       * virtual address even when running in another domain''s
address space.
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index d21909f..0752dd2 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -1126,6 +1126,34 @@ long do_vcpu_op(int cmd, int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
>          break;
>      }
>  
> +    case VCPUOP_register_runstate_memory_area:
> +    {
> +        struct vcpu_register_runstate_memory_area area;
> +        struct vcpu_runstate_info runstate;
> +
> +        rc = -EFAULT;
> +        if ( copy_from_guest(&area, arg, 1) )
> +            break;
> +
> +        if ( !guest_handle_okay(area.addr.h, 1) )
> +            break;
> +
> +        rc = 0;
> +        runstate_guest(v) = area.addr.h;
> +
> +        if ( v == current )
> +        {
> +            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
> +        }
> +        else
> +        {
> +            vcpu_runstate_get(v, &runstate);
> +            __copy_to_guest(runstate_guest(v), &runstate, 1);
> +        }
> +
> +        break;
> +    }
> +
>  #ifdef VCPU_TRAP_NMI
>      case VCPUOP_send_nmi:
>          if ( !guest_handle_is_null(arg) )

On Wed, 2013-05-01 at 20:32 +0100, Stefano Stabellini
wrote:
> Support VCPUOP_register_runstate_memory_area on ARM.
> Update_runstate_area on context switch.
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

On 02/05/2013 09:05, "Ian Campbell" <Ian.Campbell@citrix.com>
wrote:
> On Wed, 2013-05-01 at 20:32 +0100, Stefano Stabellini wrote:
>> Signed-off-by: Stefano Stabellini
<stefano.stabellini@eu.citrix.com>
> 
> Needs x86 and/or core acks, but lacks suitable CCs. Added.
Acked-by: Keir Fraser <keir@xen.org>
>> ---
>>  xen/arch/x86/domain.c |   28 ----------------------------
>>  xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
>>  2 files changed, 28 insertions(+), 28 deletions(-)
>> 
>> diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
>> index d1b6c64..87dcb73 100644
>> --- a/xen/arch/x86/domain.c
>> +++ b/xen/arch/x86/domain.c
>> @@ -960,34 +960,6 @@ arch_do_vcpu_op(
>>  
>>      switch ( cmd )
>>      {
>> -    case VCPUOP_register_runstate_memory_area:
>> -    {
>> -        struct vcpu_register_runstate_memory_area area;
>> -        struct vcpu_runstate_info runstate;
>> -
>> -        rc = -EFAULT;
>> -        if ( copy_from_guest(&area, arg, 1) )
>> -            break;
>> -
>> -        if ( !guest_handle_okay(area.addr.h, 1) )
>> -            break;
>> -
>> -        rc = 0;
>> -        runstate_guest(v) = area.addr.h;
>> -
>> -        if ( v == current )
>> -        {
>> -            __copy_to_guest(runstate_guest(v), &v->runstate,
1);
>> -        }
>> -        else
>> -        {
>> -            vcpu_runstate_get(v, &runstate);
>> -            __copy_to_guest(runstate_guest(v), &runstate, 1);
>> -        }
>> -
>> -        break;
>> -    }
>> -
>>      /*
>>       * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to
the
>> given
>>       * virtual address even when running in another domain''s
address space.
>> diff --git a/xen/common/domain.c b/xen/common/domain.c
>> index d21909f..0752dd2 100644
>> --- a/xen/common/domain.c
>> +++ b/xen/common/domain.c
>> @@ -1126,6 +1126,34 @@ long do_vcpu_op(int cmd, int vcpuid,
>> XEN_GUEST_HANDLE_PARAM(void) arg)
>>          break;
>>      }
>>  
>> +    case VCPUOP_register_runstate_memory_area:
>> +    {
>> +        struct vcpu_register_runstate_memory_area area;
>> +        struct vcpu_runstate_info runstate;
>> +
>> +        rc = -EFAULT;
>> +        if ( copy_from_guest(&area, arg, 1) )
>> +            break;
>> +
>> +        if ( !guest_handle_okay(area.addr.h, 1) )
>> +            break;
>> +
>> +        rc = 0;
>> +        runstate_guest(v) = area.addr.h;
>> +
>> +        if ( v == current )
>> +        {
>> +            __copy_to_guest(runstate_guest(v), &v->runstate,
1);
>> +        }
>> +        else
>> +        {
>> +            vcpu_runstate_get(v, &runstate);
>> +            __copy_to_guest(runstate_guest(v), &runstate, 1);
>> +        }
>> +
>> +        break;
>> +    }
>> +
>>  #ifdef VCPU_TRAP_NMI
>>      case VCPUOP_send_nmi:
>>          if ( !guest_handle_is_null(arg) )
> 
>

On Wed, 2013-05-01 at 20:32 +0100, Stefano Stabellini wrote:

I got conflicts apply this. I didn''t look to see if they related to the
problems applying the ARM guest SMP series or if it was some other
change to the underlying tree.
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> ---
>  xen/arch/x86/domain.c |   28 ----------------------------
>  xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
>  2 files changed, 28 insertions(+), 28 deletions(-)
> 
> diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
> index d1b6c64..87dcb73 100644
> --- a/xen/arch/x86/domain.c
> +++ b/xen/arch/x86/domain.c
> @@ -960,34 +960,6 @@ arch_do_vcpu_op(
>  
>      switch ( cmd )
>      {
> -    case VCPUOP_register_runstate_memory_area:
> -    {
> -        struct vcpu_register_runstate_memory_area area;
> -        struct vcpu_runstate_info runstate;
> -
> -        rc = -EFAULT;
> -        if ( copy_from_guest(&area, arg, 1) )
> -            break;
> -
> -        if ( !guest_handle_okay(area.addr.h, 1) )
> -            break;
> -
> -        rc = 0;
> -        runstate_guest(v) = area.addr.h;
> -
> -        if ( v == current )
> -        {
> -            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
> -        }
> -        else
> -        {
> -            vcpu_runstate_get(v, &runstate);
> -            __copy_to_guest(runstate_guest(v), &runstate, 1);
> -        }
> -
> -        break;
> -    }
> -
>      /*
>       * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to the
given
>       * virtual address even when running in another domain''s
address space.
> diff --git a/xen/common/domain.c b/xen/common/domain.c
> index d21909f..0752dd2 100644
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -1126,6 +1126,34 @@ long do_vcpu_op(int cmd, int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
>          break;
>      }
>  
> +    case VCPUOP_register_runstate_memory_area:
> +    {
> +        struct vcpu_register_runstate_memory_area area;
> +        struct vcpu_runstate_info runstate;
> +
> +        rc = -EFAULT;
> +        if ( copy_from_guest(&area, arg, 1) )
> +            break;
> +
> +        if ( !guest_handle_okay(area.addr.h, 1) )
> +            break;
> +
> +        rc = 0;
> +        runstate_guest(v) = area.addr.h;
> +
> +        if ( v == current )
> +        {
> +            __copy_to_guest(runstate_guest(v), &v->runstate, 1);
> +        }
> +        else
> +        {
> +            vcpu_runstate_get(v, &runstate);
> +            __copy_to_guest(runstate_guest(v), &runstate, 1);
> +        }
> +
> +        break;
> +    }
> +
>  #ifdef VCPU_TRAP_NMI
>      case VCPUOP_send_nmi:
>          if ( !guest_handle_is_null(arg) )

I guess it needs to be applied on top of the guest SMP patch series
because I don''t get any conflicts.
Let me know if you are still having issues.


On Wed, 8 May 2013, Ian Campbell wrote:
> On Wed, 2013-05-01 at 20:32 +0100, Stefano Stabellini wrote:
> 
> I got conflicts apply this. I didn''t look to see if they related
to the
> problems applying the ARM guest SMP series or if it was some other
> change to the underlying tree.
> 
> > Signed-off-by: Stefano Stabellini
<stefano.stabellini@eu.citrix.com>
> > ---
> >  xen/arch/x86/domain.c |   28 ----------------------------
> >  xen/common/domain.c   |   28 ++++++++++++++++++++++++++++
> >  2 files changed, 28 insertions(+), 28 deletions(-)
> > 
> > diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
> > index d1b6c64..87dcb73 100644
> > --- a/xen/arch/x86/domain.c
> > +++ b/xen/arch/x86/domain.c
> > @@ -960,34 +960,6 @@ arch_do_vcpu_op(
> >  
> >      switch ( cmd )
> >      {
> > -    case VCPUOP_register_runstate_memory_area:
> > -    {
> > -        struct vcpu_register_runstate_memory_area area;
> > -        struct vcpu_runstate_info runstate;
> > -
> > -        rc = -EFAULT;
> > -        if ( copy_from_guest(&area, arg, 1) )
> > -            break;
> > -
> > -        if ( !guest_handle_okay(area.addr.h, 1) )
> > -            break;
> > -
> > -        rc = 0;
> > -        runstate_guest(v) = area.addr.h;
> > -
> > -        if ( v == current )
> > -        {
> > -            __copy_to_guest(runstate_guest(v), &v->runstate,
1);
> > -        }
> > -        else
> > -        {
> > -            vcpu_runstate_get(v, &runstate);
> > -            __copy_to_guest(runstate_guest(v), &runstate, 1);
> > -        }
> > -
> > -        break;
> > -    }
> > -
> >      /*
> >       * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to
the given
> >       * virtual address even when running in another domain''s
address space.
> > diff --git a/xen/common/domain.c b/xen/common/domain.c
> > index d21909f..0752dd2 100644
> > --- a/xen/common/domain.c
> > +++ b/xen/common/domain.c
> > @@ -1126,6 +1126,34 @@ long do_vcpu_op(int cmd, int vcpuid,
XEN_GUEST_HANDLE_PARAM(void) arg)
> >          break;
> >      }
> >  
> > +    case VCPUOP_register_runstate_memory_area:
> > +    {
> > +        struct vcpu_register_runstate_memory_area area;
> > +        struct vcpu_runstate_info runstate;
> > +
> > +        rc = -EFAULT;
> > +        if ( copy_from_guest(&area, arg, 1) )
> > +            break;
> > +
> > +        if ( !guest_handle_okay(area.addr.h, 1) )
> > +            break;
> > +
> > +        rc = 0;
> > +        runstate_guest(v) = area.addr.h;
> > +
> > +        if ( v == current )
> > +        {
> > +            __copy_to_guest(runstate_guest(v), &v->runstate,
1);
> > +        }
> > +        else
> > +        {
> > +            vcpu_runstate_get(v, &runstate);
> > +            __copy_to_guest(runstate_guest(v), &runstate, 1);
> > +        }
> > +
> > +        break;
> > +    }
> > +
> >  #ifdef VCPU_TRAP_NMI
> >      case VCPUOP_send_nmi:
> >          if ( !guest_handle_is_null(arg) )
> 
> 
>

On Wed, 2013-05-08 at 12:43 +0100, Stefano Stabellini
wrote:
> I guess it needs to be applied on top of the guest SMP patch series
> because I don''t get any conflicts.
> Let me know if you are still having issues.
It applied fine now that the SMP stuff is in. thanks.

Ian.