similar to: [PATCH v2 1/6] virtio_balloon: transitional interface

"Michael S. Tsirkin" <mst at redhat.com> writes: > Virtio 1.0 doesn't include a modern balloon device. > But it's not a big change to support a transitional > balloon device: this has the advantage of supporting > existing drivers, transparently. You decided to fix the packed struct... > diff --git a/drivers/virtio/virtio_balloon.c

Virtio 1.0 doesn't include a modern balloon device. But it's not a big change to support a transitional balloon device: this has the advantage of supporting existing drivers, transparently. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_balloon.h | 11 ++++++++-- drivers/virtio/virtio_balloon.c | 43 +++++++++++++++++++++++++++++-------- 2

Virtio 1.0 doesn't include a modern balloon device. But it's not a big change to support a transitional balloon device: this has the advantage of supporting existing drivers, transparently. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_balloon.h | 11 ++++++++-- drivers/virtio/virtio_balloon.c | 43 +++++++++++++++++++++++++++++-------- 2

"Michael S. Tsirkin" <mst at redhat.com> writes: > On Tue, Apr 14, 2015 at 11:50:53AM +0200, Cornelia Huck wrote: >> On Tue, 14 Apr 2015 11:21:11 +0200 >> "Michael S. Tsirkin" <mst at redhat.com> wrote: >> >> > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h >> > index f81b220..164e0c2

"Michael S. Tsirkin" <mst at redhat.com> writes: > On Tue, Apr 14, 2015 at 11:50:53AM +0200, Cornelia Huck wrote: >> On Tue, 14 Apr 2015 11:21:11 +0200 >> "Michael S. Tsirkin" <mst at redhat.com> wrote: >> >> > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h >> > index f81b220..164e0c2

On Tue, 14 Apr 2015 11:21:11 +0200 "Michael S. Tsirkin" <mst at redhat.com> wrote: > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h > index f81b220..164e0c2 100644 > --- a/include/uapi/linux/virtio_balloon.h > +++ b/include/uapi/linux/virtio_balloon.h > @@ -52,15 +52,31 @@ struct virtio_balloon_config { > #define

On Tue, 14 Apr 2015 11:21:11 +0200 "Michael S. Tsirkin" <mst at redhat.com> wrote: > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h > index f81b220..164e0c2 100644 > --- a/include/uapi/linux/virtio_balloon.h > +++ b/include/uapi/linux/virtio_balloon.h > @@ -52,15 +52,31 @@ struct virtio_balloon_config { > #define

On Fri, Jul 10, 2020 at 09:13:41AM -0700, Alexander Duyck wrote: > On Fri, Jul 10, 2020 at 4:31 AM Michael S. Tsirkin <mst at redhat.com> wrote: > > > > Page reporting features were never supported by legacy hypervisors. > > Supporting them poses a problem: should we use native endian-ness (like > > current code assumes)? Or little endian-ness like the virtio spec

On Fri, Jul 10, 2020 at 09:13:41AM -0700, Alexander Duyck wrote: > On Fri, Jul 10, 2020 at 4:31 AM Michael S. Tsirkin <mst at redhat.com> wrote: > > > > Page reporting features were never supported by legacy hypervisors. > > Supporting them poses a problem: should we use native endian-ness (like > > current code assumes)? Or little endian-ness like the virtio spec

Virtio 1.0 doesn't include a modern balloon device. But it's not a big change to support a transitional balloon device: this has the advantage of supporting existing drivers, transparently. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_balloon.h | 6 ++++++ drivers/virtio/virtio_balloon.c | 8 ++++++-- 2 files changed, 12 insertions(+), 2

Virtio 1.0 doesn't include a modern balloon device. But it's not a big change to support a transitional balloon device: this has the advantage of supporting existing drivers, transparently. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- include/uapi/linux/virtio_balloon.h | 6 ++++++ drivers/virtio/virtio_balloon.c | 8 ++++++-- 2 files changed, 12 insertions(+), 2

On Tue, Apr 14, 2015 at 11:50:53AM +0200, Cornelia Huck wrote: > On Tue, 14 Apr 2015 11:21:11 +0200 > "Michael S. Tsirkin" <mst at redhat.com> wrote: > > > diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h > > index f81b220..164e0c2 100644 > > --- a/include/uapi/linux/virtio_balloon.h > > +++

On Tue, Apr 14, 2015 at 10:24:38AM +0200, Cornelia Huck wrote: > On Tue, 14 Apr 2015 10:42:56 +0930 > Rusty Russell <rusty at rustcorp.com.au> wrote: > > > "Michael S. Tsirkin" <mst at redhat.com> writes: > > > On Wed, Apr 01, 2015 at 02:57:35PM +0200, Michael S. Tsirkin wrote: > > >> Virtio 1.0 doesn't include a modern balloon device.

Looks like we are better off sticking with the misaligned stat struct, to reduce the amount of virtio 1 specific code in balloon. So let's do it. Add a detailed comment to reduce the chance people copy this bad example. This also fixes a bug on BE architectures: tag should use cpu_to_le16, not cpu_to_le32. Acked-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael

Looks like we are better off sticking with the misaligned stat struct, to reduce the amount of virtio 1 specific code in balloon. So let's do it. Add a detailed comment to reduce the chance people copy this bad example. This also fixes a bug on BE architectures: tag should use cpu_to_le16, not cpu_to_le32. Acked-by: Cornelia Huck <cornelia.huck at de.ibm.com> Signed-off-by: Michael

The deflation request to the target, which isn't unaligned to the guest page size causes endless deflation and inflation actions. For example, we receive the flooding QMP events for the changes on memory balloon's size after a deflation request to the unaligned target is sent for the ARM64 guest, where we have 64KB base page size. /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64

Both v and vb->num_pages are u32 and unsigned int respectively. If v is less than vb->num_pages (and it is, when deflating the balloon), the result is a very large 32-bit number. Since we're returning a s64, instead of getting the same negative number we desire, we get a very large positive number. This handles the case where v < vb->num_pages and ensures we get a small,

Both v and vb->num_pages are u32 and unsigned int respectively. If v is less than vb->num_pages (and it is, when deflating the balloon), the result is a very large 32-bit number. Since we're returning a s64, instead of getting the same negative number we desire, we get a very large positive number. This handles the case where v < vb->num_pages and ensures we get a small,

Export the number of successful and failed hugetlb page allocations via the virtio balloon driver. These 2 counts come directly from the vm_events HTLB_BUDDY_PGALLOC and HTLB_BUDDY_PGALLOC_FAIL. Signed-off-by: Jonathan Helman <jonathan.helman at oracle.com> --- drivers/virtio/virtio_balloon.c | 6 ++++++ include/uapi/linux/virtio_balloon.h | 4 +++- 2 files changed, 9 insertions(+), 1

Export the number of successful and failed hugetlb page allocations via the virtio balloon driver. These 2 counts come directly from the vm_events HTLB_BUDDY_PGALLOC and HTLB_BUDDY_PGALLOC_FAIL. Signed-off-by: Jonathan Helman <jonathan.helman at oracle.com> --- drivers/virtio/virtio_balloon.c | 6 ++++++ include/uapi/linux/virtio_balloon.h | 4 +++- 2 files changed, 9 insertions(+), 1