Re: [Qemu-devel] [RFC 3/5] virtio-balloon: Rework ballon_page() interface

2018-10-13 Thread David Gibson 
On Fri, Oct 12, 2018 at 09:46:16AM +0200, David Hildenbrand wrote:
> On 12/10/2018 05:24, David Gibson wrote:
> > This replaces the balloon_page() internal interface with
> > ballon_inflate_page(), with a slightly different interface.  The new
> > interface will make future alterations simpler.
> > 
> > Signed-off-by: David Gibson 
> > ---
> >  hw/virtio/virtio-balloon.c | 17 +++--
> >  1 file changed, 7 insertions(+), 10 deletions(-)
> > 
> > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
> > index e8611aab0e..7229afad6e 100644
> > --- a/hw/virtio/virtio-balloon.c
> > +++ b/hw/virtio/virtio-balloon.c
> > @@ -33,11 +33,11 @@
> >  
> >  #define BALLOON_PAGE_SIZE  (1 << VIRTIO_BALLOON_PFN_SHIFT)
> >  
> > -static void balloon_page(void *addr, int deflate)
> > +static void balloon_inflate_page(VirtIOBalloon *balloon,
> > + MemoryRegion *mr, hwaddr offset)
> >  {
> > -if (!qemu_balloon_is_inhibited() && !deflate) {
> > -qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
> > -}
> > +void *addr = memory_region_get_ram_ptr(mr) + offset;
> 
> I prefer an empty line here

Ok.

> > +qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
> >  }
> >  
> >  static const char *balloon_stat_names[] = {
> > @@ -222,7 +222,6 @@ static void virtio_balloon_handle_output(VirtIODevice 
> > *vdev, VirtQueue *vq)
> >  
> >  while (iov_to_buf(elem->out_sg, elem->out_num, offset, , 4) == 
> > 4) {
> >  hwaddr pa;
> > -hwaddr addr;
> >  int p = virtio_ldl_p(vdev, );
> >  
> >  pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT;
> > @@ -244,11 +243,9 @@ static void virtio_balloon_handle_output(VirtIODevice 
> > *vdev, VirtQueue *vq)
> >  
> >  
> > trace_virtio_balloon_handle_output(memory_region_name(section.mr),
> > pa);
> > -/* Using memory_region_get_ram_ptr is bending the rules a bit, 
> > but
> > -   should be OK because we only want a single page.  */
> > -addr = section.offset_within_region;
> > -balloon_page(memory_region_get_ram_ptr(section.mr) + addr,
> > - !!(vq == s->dvq));
> > +if (!qemu_balloon_is_inhibited() && vq != s->dvq) {
> > +balloon_inflate_page(s, section.mr, 
> > section.offset_within_region);
> > +}
> >  memory_region_unref(section.mr);
> >  }
> >  
> > 
> 
> Reviewed-by: David Hildenbrand 
> 

-- 
David Gibson| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson


signature.asc
Description: PGP signature

Re: [Qemu-devel] [RFC 3/5] virtio-balloon: Rework ballon_page() interface

2018-10-12 Thread David Hildenbrand 
On 12/10/2018 05:24, David Gibson wrote:
> This replaces the balloon_page() internal interface with
> ballon_inflate_page(), with a slightly different interface.  The new
> interface will make future alterations simpler.
> 
> Signed-off-by: David Gibson 
> ---
>  hw/virtio/virtio-balloon.c | 17 +++--
>  1 file changed, 7 insertions(+), 10 deletions(-)
> 
> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
> index e8611aab0e..7229afad6e 100644
> --- a/hw/virtio/virtio-balloon.c
> +++ b/hw/virtio/virtio-balloon.c
> @@ -33,11 +33,11 @@
>  
>  #define BALLOON_PAGE_SIZE  (1 << VIRTIO_BALLOON_PFN_SHIFT)
>  
> -static void balloon_page(void *addr, int deflate)
> +static void balloon_inflate_page(VirtIOBalloon *balloon,
> + MemoryRegion *mr, hwaddr offset)
>  {
> -if (!qemu_balloon_is_inhibited() && !deflate) {
> -qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
> -}
> +void *addr = memory_region_get_ram_ptr(mr) + offset;

I prefer an empty line here

> +qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
>  }
>  
>  static const char *balloon_stat_names[] = {
> @@ -222,7 +222,6 @@ static void virtio_balloon_handle_output(VirtIODevice 
> *vdev, VirtQueue *vq)
>  
>  while (iov_to_buf(elem->out_sg, elem->out_num, offset, , 4) == 
> 4) {
>  hwaddr pa;
> -hwaddr addr;
>  int p = virtio_ldl_p(vdev, );
>  
>  pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT;
> @@ -244,11 +243,9 @@ static void virtio_balloon_handle_output(VirtIODevice 
> *vdev, VirtQueue *vq)
>  
>  
> trace_virtio_balloon_handle_output(memory_region_name(section.mr),
> pa);
> -/* Using memory_region_get_ram_ptr is bending the rules a bit, 
> but
> -   should be OK because we only want a single page.  */
> -addr = section.offset_within_region;
> -balloon_page(memory_region_get_ram_ptr(section.mr) + addr,
> - !!(vq == s->dvq));
> +if (!qemu_balloon_is_inhibited() && vq != s->dvq) {
> +balloon_inflate_page(s, section.mr, 
> section.offset_within_region);
> +}
>  memory_region_unref(section.mr);
>  }
>  
> 

Reviewed-by: David Hildenbrand 

-- 

Thanks,

David / dhildenb

[Qemu-devel] [RFC 3/5] virtio-balloon: Rework ballon_page() interface

2018-10-11 Thread David Gibson 
This replaces the balloon_page() internal interface with
ballon_inflate_page(), with a slightly different interface.  The new
interface will make future alterations simpler.

Signed-off-by: David Gibson 
---
 hw/virtio/virtio-balloon.c | 17 +++--
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index e8611aab0e..7229afad6e 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -33,11 +33,11 @@
 
 #define BALLOON_PAGE_SIZE  (1 << VIRTIO_BALLOON_PFN_SHIFT)
 
-static void balloon_page(void *addr, int deflate)
+static void balloon_inflate_page(VirtIOBalloon *balloon,
+ MemoryRegion *mr, hwaddr offset)
 {
-if (!qemu_balloon_is_inhibited() && !deflate) {
-qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
-}
+void *addr = memory_region_get_ram_ptr(mr) + offset;
+qemu_madvise(addr, BALLOON_PAGE_SIZE, QEMU_MADV_DONTNEED);
 }
 
 static const char *balloon_stat_names[] = {
@@ -222,7 +222,6 @@ static void virtio_balloon_handle_output(VirtIODevice 
*vdev, VirtQueue *vq)
 
 while (iov_to_buf(elem->out_sg, elem->out_num, offset, , 4) == 4) {
 hwaddr pa;
-hwaddr addr;
 int p = virtio_ldl_p(vdev, );
 
 pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT;
@@ -244,11 +243,9 @@ static void virtio_balloon_handle_output(VirtIODevice 
*vdev, VirtQueue *vq)
 
 trace_virtio_balloon_handle_output(memory_region_name(section.mr),
pa);
-/* Using memory_region_get_ram_ptr is bending the rules a bit, but
-   should be OK because we only want a single page.  */
-addr = section.offset_within_region;
-balloon_page(memory_region_get_ram_ptr(section.mr) + addr,
- !!(vq == s->dvq));
+if (!qemu_balloon_is_inhibited() && vq != s->dvq) {
+balloon_inflate_page(s, section.mr, 
section.offset_within_region);
+}
 memory_region_unref(section.mr);
 }
 
-- 
2.17.1