[ovs-dev,1/2] dpdk docs: Drop qemu-kvm for qemu-system-x86_64.

Message ID 1523442352-164297-1-git-send-email-tiago.lam@intel.com
State Accepted
Delegated to: Ian Stokes
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Series
  • [ovs-dev,1/2] dpdk docs: Drop qemu-kvm for qemu-system-x86_64.
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Commit Message

Lam, Tiago April 11, 2018, 10:25 a.m.
When explaining on how to add vhost-user ports to a guest, using
libvirt, point to the qemu-system-x86_64 binary by default, instead of
using qemu-kvm. The latter has been made obsolete and dropped from a
number of distributions (although it is still available on Fedora).

This has been verified on both a Fedora 27 image and a Ubuntu 16.04 LTS
image.

Signed-off-by: Tiago Lam <tiago.lam@intel.com>
---
 Documentation/topics/dpdk/vhost-user.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Aaron Conole April 11, 2018, 1:53 p.m. | #1
Tiago Lam <tiago.lam@intel.com> writes:

> When explaining on how to add vhost-user ports to a guest, using
> libvirt, point to the qemu-system-x86_64 binary by default, instead of
> using qemu-kvm. The latter has been made obsolete and dropped from a
> number of distributions (although it is still available on Fedora).
>
> This has been verified on both a Fedora 27 image and a Ubuntu 16.04 LTS
> image.
>
> Signed-off-by: Tiago Lam <tiago.lam@intel.com>
> ---
>  Documentation/topics/dpdk/vhost-user.rst | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/Documentation/topics/dpdk/vhost-user.rst b/Documentation/topics/dpdk/vhost-user.rst
> index ca8a328..74bab78 100644
> --- a/Documentation/topics/dpdk/vhost-user.rst
> +++ b/Documentation/topics/dpdk/vhost-user.rst
> @@ -401,7 +401,7 @@ Sample XML
>        <on_reboot>restart</on_reboot>
>        <on_crash>destroy</on_crash>
>        <devices>
> -        <emulator>/usr/bin/qemu-kvm</emulator>

Looks like this isn't even a proper path on some systems.  For example,
RHEL7 it's:

  /usr/libexec/qemu-kvm

So it's doubly wrong.

> +        <emulator>/usr/bin/qemu-system-x86_64</emulator>
>          <disk type='file' device='disk'>
>            <driver name='qemu' type='qcow2' cache='none'/>
>            <source file='/root/CentOS7_x86_64.qcow2'/>

On the other hand, on my RHEL7.4 system, I don't have
qemu-system-x86_64, but I do have qemu-kvm.

I do like cookbook examples, but it seems that sometimes the care and
feeding of these sections gets cumbersome.  Maybe there's a way of
including just the xml portions we need for a vhost-enabled libvirt xml
configuration?

Just a thought.

Anyway:

  Acked-by: Aaron Conole <aconole@redhat.com>

Thanks, Tiago!
Lam, Tiago April 12, 2018, 7:26 a.m. | #2
On 11/04/2018 14:53, Aaron Conole wrote:
> Tiago Lam <tiago.lam@intel.com> writes:
> 
>> When explaining on how to add vhost-user ports to a guest, using
>> libvirt, point to the qemu-system-x86_64 binary by default, instead of
>> using qemu-kvm. The latter has been made obsolete and dropped from a
>> number of distributions (although it is still available on Fedora).
>>
>> This has been verified on both a Fedora 27 image and a Ubuntu 16.04 LTS
>> image.
>>
>> Signed-off-by: Tiago Lam <tiago.lam@intel.com>
>> ---
>>   Documentation/topics/dpdk/vhost-user.rst | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/Documentation/topics/dpdk/vhost-user.rst b/Documentation/topics/dpdk/vhost-user.rst
>> index ca8a328..74bab78 100644
>> --- a/Documentation/topics/dpdk/vhost-user.rst
>> +++ b/Documentation/topics/dpdk/vhost-user.rst
>> @@ -401,7 +401,7 @@ Sample XML
>>         <on_reboot>restart</on_reboot>
>>         <on_crash>destroy</on_crash>
>>         <devices>
>> -        <emulator>/usr/bin/qemu-kvm</emulator>
> 
> Looks like this isn't even a proper path on some systems.  For example,
> RHEL7 it's:
> 
>    /usr/libexec/qemu-kvm
> 
> So it's doubly wrong.
> 
>> +        <emulator>/usr/bin/qemu-system-x86_64</emulator>
>>           <disk type='file' device='disk'>
>>             <driver name='qemu' type='qcow2' cache='none'/>
>>             <source file='/root/CentOS7_x86_64.qcow2'/>
> 
> On the other hand, on my RHEL7.4 system, I don't have
> qemu-system-x86_64, but I do have qemu-kvm.
> 

That's unfortunate. I would have thought that Fedora derivatives, at 
least, would have it (I've checked on Fedora 27). But my main reason to 
stick with `/usr/bin/qemu-system-x86_64` is because it is used in 
another part of the guide already [1], so this keeps it consistent.

[1] 
http://docs.openvswitch.org/en/latest/howto/dpdk/#phy-vm-phy-vhost-loopback

> I do like cookbook examples, but it seems that sometimes the care and
> feeding of these sections gets cumbersome.  Maybe there's a way of
> including just the xml portions we need for a vhost-enabled libvirt xml
> configuration?
> 
> Just a thought.

I agree on that. But if I'm understanding correctly then the user would 
need to find a template configuration himself (and hopefully that would 
come pointing to the right binary on his system). But maybe that's 
something we're comfortable with.

> Anyway:
> 
>    Acked-by: Aaron Conole <aconole@redhat.com>

Thanks, Aaron.
Stokes, Ian April 19, 2018, 8:40 a.m. | #3
> Tiago Lam <tiago.lam@intel.com> writes:
> 
> > When explaining on how to add vhost-user ports to a guest, using
> > libvirt, point to the qemu-system-x86_64 binary by default, instead of
> > using qemu-kvm. The latter has been made obsolete and dropped from a
> > number of distributions (although it is still available on Fedora).
> >
> > This has been verified on both a Fedora 27 image and a Ubuntu 16.04
> > LTS image.
> >
> > Signed-off-by: Tiago Lam <tiago.lam@intel.com>
> > ---
> >  Documentation/topics/dpdk/vhost-user.rst | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/Documentation/topics/dpdk/vhost-user.rst
> > b/Documentation/topics/dpdk/vhost-user.rst
> > index ca8a328..74bab78 100644
> > --- a/Documentation/topics/dpdk/vhost-user.rst
> > +++ b/Documentation/topics/dpdk/vhost-user.rst
> > @@ -401,7 +401,7 @@ Sample XML
> >        <on_reboot>restart</on_reboot>
> >        <on_crash>destroy</on_crash>
> >        <devices>
> > -        <emulator>/usr/bin/qemu-kvm</emulator>
> 
> Looks like this isn't even a proper path on some systems.  For example,
> RHEL7 it's:
> 
>   /usr/libexec/qemu-kvm
> 
> So it's doubly wrong.
> 
> > +        <emulator>/usr/bin/qemu-system-x86_64</emulator>
> >          <disk type='file' device='disk'>
> >            <driver name='qemu' type='qcow2' cache='none'/>
> >            <source file='/root/CentOS7_x86_64.qcow2'/>
> 
> On the other hand, on my RHEL7.4 system, I don't have qemu-system-x86_64,
> but I do have qemu-kvm.
> 
> I do like cookbook examples, but it seems that sometimes the care and
> feeding of these sections gets cumbersome.  Maybe there's a way of
> including just the xml portions we need for a vhost-enabled libvirt xml
> configuration?
> 
> Just a thought.
> 
> Anyway:
> 
>   Acked-by: Aaron Conole <aconole@redhat.com>

Thanks all, pushed to DPDK_MERGE, I'll back port this to previous releases also.

Ian

> 
> Thanks, Tiago!
> _______________________________________________
> dev mailing list
> dev@openvswitch.org
> https://mail.openvswitch.org/mailman/listinfo/ovs-dev

Patch

diff --git a/Documentation/topics/dpdk/vhost-user.rst b/Documentation/topics/dpdk/vhost-user.rst
index ca8a328..74bab78 100644
--- a/Documentation/topics/dpdk/vhost-user.rst
+++ b/Documentation/topics/dpdk/vhost-user.rst
@@ -401,7 +401,7 @@  Sample XML
       <on_reboot>restart</on_reboot>
       <on_crash>destroy</on_crash>
       <devices>
-        <emulator>/usr/bin/qemu-kvm</emulator>
+        <emulator>/usr/bin/qemu-system-x86_64</emulator>
         <disk type='file' device='disk'>
           <driver name='qemu' type='qcow2' cache='none'/>
           <source file='/root/CentOS7_x86_64.qcow2'/>