Displaying 9 results from an estimated 9 matches for "hyprevisor".
Did you mean:
hypervisor
2015 Dec 17
2
[PATCH] virtio_ring: use smp_store_mb
...CONFIG_SMP
smp_store_mb does not include this.
> smp_mb(), as (should be) used by smp_store_mb() does not provide a
> barrier against IO. mb() otoh does.
>
> Since this is virtIO I would expect you always want mb().
No because it's VIRTio not real io :) It just switches to the hyprevisor
mode - kind of like a function call really.
The weak_barriers flag is cleared for when it's used
with real devices with real IO.
All this is explained in some detail at the top of
include/linux/virtio.h
--
MST
2015 Dec 17
2
[PATCH] virtio_ring: use smp_store_mb
...CONFIG_SMP
smp_store_mb does not include this.
> smp_mb(), as (should be) used by smp_store_mb() does not provide a
> barrier against IO. mb() otoh does.
>
> Since this is virtIO I would expect you always want mb().
No because it's VIRTio not real io :) It just switches to the hyprevisor
mode - kind of like a function call really.
The weak_barriers flag is cleared for when it's used
with real devices with real IO.
All this is explained in some detail at the top of
include/linux/virtio.h
--
MST
2012 Sep 09
2
[PATCH] virtio-spec: balloon: MUST_TELL_HOST is optional
Drivers treat MUST_TELL_HOST as optional: windows drivers do not ack it
and expect this means they can tell host *after* deflate. This was not
the intent but the documentation was not very clear on this point.
Luckily hyprevisors did not implement this feature yet so to provide
guidance for future devices make spec match drivers expectations, and
clarify that this feature only has effect if negotiated.
This is needed as recent developments in kvm (memory
region rework and the addition of vfio) finally make
it practical to...
2012 Sep 09
2
[PATCH] virtio-spec: balloon: MUST_TELL_HOST is optional
Drivers treat MUST_TELL_HOST as optional: windows drivers do not ack it
and expect this means they can tell host *after* deflate. This was not
the intent but the documentation was not very clear on this point.
Luckily hyprevisors did not implement this feature yet so to provide
guidance for future devices make spec match drivers expectations, and
clarify that this feature only has effect if negotiated.
This is needed as recent developments in kvm (memory
region rework and the addition of vfio) finally make
it practical to...
2015 Dec 17
0
[PATCH] virtio_ring: use smp_store_mb
...state.
>
>
> > smp_mb(), as (should be) used by smp_store_mb() does not provide a
> > barrier against IO. mb() otoh does.
> >
> > Since this is virtIO I would expect you always want mb().
>
> No because it's VIRTio not real io :) It just switches to the hyprevisor
> mode - kind of like a function call really.
> The weak_barriers flag is cleared for when it's used
> with real devices with real IO.
>
>
> All this is explained in some detail at the top of
> include/linux/virtio.h
I did read that, it didn't make any sense wrt the...
2015 Dec 17
4
[PATCH] virtio_ring: use smp_store_mb
We need a full barrier after writing out event index, using smp_store_mb
there seems better than open-coding.
As usual, we need a wrapper to account for strong barriers/non smp.
It's tempting to use this in vhost as well, for that, we'll
need a variant of smp_store_mb that works on __user pointers.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
Seems to give a speedup
2015 Dec 17
4
[PATCH] virtio_ring: use smp_store_mb
We need a full barrier after writing out event index, using smp_store_mb
there seems better than open-coding.
As usual, we need a wrapper to account for strong barriers/non smp.
It's tempting to use this in vhost as well, for that, we'll
need a variant of smp_store_mb that works on __user pointers.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
Seems to give a speedup
2015 Dec 17
3
[PATCH] virtio_ring: use smp_store_mb
...> smp_mb(), as (should be) used by smp_store_mb() does not provide a
> > > barrier against IO. mb() otoh does.
> > >
> > > Since this is virtIO I would expect you always want mb().
> >
> > No because it's VIRTio not real io :) It just switches to the hyprevisor
> > mode - kind of like a function call really.
> > The weak_barriers flag is cleared for when it's used
> > with real devices with real IO.
> >
> >
> > All this is explained in some detail at the top of
> > include/linux/virtio.h
>
> I did rea...
2015 Dec 17
3
[PATCH] virtio_ring: use smp_store_mb
...> smp_mb(), as (should be) used by smp_store_mb() does not provide a
> > > barrier against IO. mb() otoh does.
> > >
> > > Since this is virtIO I would expect you always want mb().
> >
> > No because it's VIRTio not real io :) It just switches to the hyprevisor
> > mode - kind of like a function call really.
> > The weak_barriers flag is cleared for when it's used
> > with real devices with real IO.
> >
> >
> > All this is explained in some detail at the top of
> > include/linux/virtio.h
>
> I did rea...