Displaying 7 results from an estimated 7 matches for "some_cold_label".
2017 Sep 06
2
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
..., Waiman Long wrote:
> For clarification, I was actually asking if you consider just adding one
> more jump label to skip it for Xen/KVM instead of making
> virt_spin_lock() a pv-op.
I don't understand. What performance are you worried about. Native will
now do: "xor rax,rax; jnz some_cold_label" that's fairly trival code.
2017 Sep 06
2
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
..., Waiman Long wrote:
> For clarification, I was actually asking if you consider just adding one
> more jump label to skip it for Xen/KVM instead of making
> virt_spin_lock() a pv-op.
I don't understand. What performance are you worried about. Native will
now do: "xor rax,rax; jnz some_cold_label" that's fairly trival code.
2017 Sep 06
1
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
...cation, I was actually asking if you consider just adding one
> >> more jump label to skip it for Xen/KVM instead of making
> >> virt_spin_lock() a pv-op.
> > I don't understand. What performance are you worried about. Native will
> > now do: "xor rax,rax; jnz some_cold_label" that's fairly trival code.
>
> It is not native that I am talking about. I am worry about VM with
> non-Xen/KVM hypervisor where virt_spin_lock() will actually be called.
> Now that function will become a callee-saved function call instead of
> being inlined into the nativ...
2017 Sep 06
1
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
...cation, I was actually asking if you consider just adding one
> >> more jump label to skip it for Xen/KVM instead of making
> >> virt_spin_lock() a pv-op.
> > I don't understand. What performance are you worried about. Native will
> > now do: "xor rax,rax; jnz some_cold_label" that's fairly trival code.
>
> It is not native that I am talking about. I am worry about VM with
> non-Xen/KVM hypervisor where virt_spin_lock() will actually be called.
> Now that function will become a callee-saved function call instead of
> being inlined into the nativ...
2017 Sep 06
0
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
...>> For clarification, I was actually asking if you consider just adding one
>> more jump label to skip it for Xen/KVM instead of making
>> virt_spin_lock() a pv-op.
> I don't understand. What performance are you worried about. Native will
> now do: "xor rax,rax; jnz some_cold_label" that's fairly trival code.
It is not native that I am talking about. I am worry about VM with
non-Xen/KVM hypervisor where virt_spin_lock() will actually be called.
Now that function will become a callee-saved function call instead of
being inlined into the native slowpath function.
Che...
2017 Sep 05
3
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
On 09/05/2017 10:18 AM, Juergen Gross wrote:
> On 05/09/17 16:10, Waiman Long wrote:
>> On 09/05/2017 09:24 AM, Juergen Gross wrote:
>>> There are cases where a guest tries to switch spinlocks to bare metal
>>> behavior (e.g. by setting "xen_nopvspin" boot parameter). Today this
>>> has the downside of falling back to unfair test and set scheme for
2017 Sep 05
3
[PATCH 3/4] paravirt: add virt_spin_lock pvops function
On 09/05/2017 10:18 AM, Juergen Gross wrote:
> On 05/09/17 16:10, Waiman Long wrote:
>> On 09/05/2017 09:24 AM, Juergen Gross wrote:
>>> There are cases where a guest tries to switch spinlocks to bare metal
>>> behavior (e.g. by setting "xen_nopvspin" boot parameter). Today this
>>> has the downside of falling back to unfair test and set scheme for