Re: [PATCH v2] virtio-pci: correctly set virtio pci queue mem multiplier

2024-02-25 Thread Jason Wang 
On Tue, Feb 20, 2024 at 3:41 PM Michael S. Tsirkin  wrote:
>
> On Tue, Feb 20, 2024 at 12:39:35PM +0530, Srujana Challa wrote:
> > Currently, virtio_pci_queue_mem_mult function always returns 4K
> > when VIRTIO_PCI_FLAG_PAGE_PER_VQ is set. But this won't
> > work for vhost vdpa when host has page size other than 4K.
> > This patch introduces a new property(page-per-vdpa-vq) for vdpa
> > use case to fix the same.
> >
> > Signed-off-by: Srujana Challa 
> > ---
> > v1->v2:
> > - Introduced a new property to get virtqueue mem multiplier for
> >   vdpa use case.
>
>
> OK, I would maybe call it host-page-per-vq?
>
> Jason?
>

I agree.

Thanks

> >  hw/virtio/virtio-pci.c | 10 --
> >  include/hw/virtio/virtio-pci.h |  5 +
> >  2 files changed, 13 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > index 1a7039fb0c..28dd6ab8b5 100644
> > --- a/hw/virtio/virtio-pci.c
> > +++ b/hw/virtio/virtio-pci.c
> > @@ -320,8 +320,12 @@ static bool virtio_pci_ioeventfd_enabled(DeviceState 
> > *d)
> >
> >  static inline int virtio_pci_queue_mem_mult(struct VirtIOPCIProxy *proxy)
> >  {
> > -return (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ?
> > -QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4;
> > +if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ)
> > +return QEMU_VIRTIO_PCI_QUEUE_MEM_MULT;
> > +else if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ)
> > +return qemu_real_host_page_size();
> > +else
> > +return 4;
> >  }
> >
> >  static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier 
> > *notifier,
> > @@ -2301,6 +2305,8 @@ static Property virtio_pci_properties[] = {
> >  VIRTIO_PCI_FLAG_INIT_FLR_BIT, true),
> >  DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags,
> >  VIRTIO_PCI_FLAG_AER_BIT, false),
> > +DEFINE_PROP_BIT("page-per-vdpa-vq", VirtIOPCIProxy, flags,
> > +VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT, false),
> >  DEFINE_PROP_END_OF_LIST(),
> >  };
> >
> > diff --git a/include/hw/virtio/virtio-pci.h b/include/hw/virtio/virtio-pci.h
> > index 59d88018c1..10a30c26a2 100644
> > --- a/include/hw/virtio/virtio-pci.h
> > +++ b/include/hw/virtio/virtio-pci.h
> > @@ -43,6 +43,7 @@ enum {
> >  VIRTIO_PCI_FLAG_INIT_FLR_BIT,
> >  VIRTIO_PCI_FLAG_AER_BIT,
> >  VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT,
> > +VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT,
> >  };
> >
> >  /* Need to activate work-arounds for buggy guests at vmstate load. */
> > @@ -89,6 +90,10 @@ enum {
> >  #define VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED \
> >(1 << VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT)
> >
> > +/* page per vdpa vq flag to be used for vhost vdpa backends */
> > +#define VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ \
> > +(1 << VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT)
> > +
> >  typedef struct {
> >  MSIMessage msg;
> >  int virq;
> > --
> > 2.25.1
>

Re: [PATCH v2] virtio-pci: correctly set virtio pci queue mem multiplier

2024-02-19 Thread Michael S. Tsirkin 
On Tue, Feb 20, 2024 at 12:39:35PM +0530, Srujana Challa wrote:
> Currently, virtio_pci_queue_mem_mult function always returns 4K
> when VIRTIO_PCI_FLAG_PAGE_PER_VQ is set. But this won't
> work for vhost vdpa when host has page size other than 4K.
> This patch introduces a new property(page-per-vdpa-vq) for vdpa
> use case to fix the same.
> 
> Signed-off-by: Srujana Challa 
> ---
> v1->v2:
> - Introduced a new property to get virtqueue mem multiplier for
>   vdpa use case.


OK, I would maybe call it host-page-per-vq?

Jason?

>  hw/virtio/virtio-pci.c | 10 --
>  include/hw/virtio/virtio-pci.h |  5 +
>  2 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index 1a7039fb0c..28dd6ab8b5 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -320,8 +320,12 @@ static bool virtio_pci_ioeventfd_enabled(DeviceState *d)
>  
>  static inline int virtio_pci_queue_mem_mult(struct VirtIOPCIProxy *proxy)
>  {
> -return (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ?
> -QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4;
> +if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ)
> +return QEMU_VIRTIO_PCI_QUEUE_MEM_MULT;
> +else if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ)
> +return qemu_real_host_page_size();
> +else
> +return 4;
>  }
>  
>  static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier 
> *notifier,
> @@ -2301,6 +2305,8 @@ static Property virtio_pci_properties[] = {
>  VIRTIO_PCI_FLAG_INIT_FLR_BIT, true),
>  DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags,
>  VIRTIO_PCI_FLAG_AER_BIT, false),
> +DEFINE_PROP_BIT("page-per-vdpa-vq", VirtIOPCIProxy, flags,
> +VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT, false),
>  DEFINE_PROP_END_OF_LIST(),
>  };
>  
> diff --git a/include/hw/virtio/virtio-pci.h b/include/hw/virtio/virtio-pci.h
> index 59d88018c1..10a30c26a2 100644
> --- a/include/hw/virtio/virtio-pci.h
> +++ b/include/hw/virtio/virtio-pci.h
> @@ -43,6 +43,7 @@ enum {
>  VIRTIO_PCI_FLAG_INIT_FLR_BIT,
>  VIRTIO_PCI_FLAG_AER_BIT,
>  VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT,
> +VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT,
>  };
>  
>  /* Need to activate work-arounds for buggy guests at vmstate load. */
> @@ -89,6 +90,10 @@ enum {
>  #define VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED \
>(1 << VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT)
>  
> +/* page per vdpa vq flag to be used for vhost vdpa backends */
> +#define VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ \
> +(1 << VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT)
> +
>  typedef struct {
>  MSIMessage msg;
>  int virq;
> -- 
> 2.25.1

[PATCH v2] virtio-pci: correctly set virtio pci queue mem multiplier

2024-02-19 Thread Srujana Challa 
Currently, virtio_pci_queue_mem_mult function always returns 4K
when VIRTIO_PCI_FLAG_PAGE_PER_VQ is set. But this won't
work for vhost vdpa when host has page size other than 4K.
This patch introduces a new property(page-per-vdpa-vq) for vdpa
use case to fix the same.

Signed-off-by: Srujana Challa 
---
v1->v2:
- Introduced a new property to get virtqueue mem multiplier for
  vdpa use case.

 hw/virtio/virtio-pci.c | 10 --
 include/hw/virtio/virtio-pci.h |  5 +
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 1a7039fb0c..28dd6ab8b5 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -320,8 +320,12 @@ static bool virtio_pci_ioeventfd_enabled(DeviceState *d)
 
 static inline int virtio_pci_queue_mem_mult(struct VirtIOPCIProxy *proxy)
 {
-return (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ?
-QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4;
+if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ)
+return QEMU_VIRTIO_PCI_QUEUE_MEM_MULT;
+else if (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ)
+return qemu_real_host_page_size();
+else
+return 4;
 }
 
 static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier *notifier,
@@ -2301,6 +2305,8 @@ static Property virtio_pci_properties[] = {
 VIRTIO_PCI_FLAG_INIT_FLR_BIT, true),
 DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags,
 VIRTIO_PCI_FLAG_AER_BIT, false),
+DEFINE_PROP_BIT("page-per-vdpa-vq", VirtIOPCIProxy, flags,
+VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT, false),
 DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/include/hw/virtio/virtio-pci.h b/include/hw/virtio/virtio-pci.h
index 59d88018c1..10a30c26a2 100644
--- a/include/hw/virtio/virtio-pci.h
+++ b/include/hw/virtio/virtio-pci.h
@@ -43,6 +43,7 @@ enum {
 VIRTIO_PCI_FLAG_INIT_FLR_BIT,
 VIRTIO_PCI_FLAG_AER_BIT,
 VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT,
+VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT,
 };
 
 /* Need to activate work-arounds for buggy guests at vmstate load. */
@@ -89,6 +90,10 @@ enum {
 #define VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED \
   (1 << VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT)
 
+/* page per vdpa vq flag to be used for vhost vdpa backends */
+#define VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ \
+(1 << VIRTIO_PCI_FLAG_PAGE_PER_VDPA_VQ_BIT)
+
 typedef struct {
 MSIMessage msg;
 int virq;
-- 
2.25.1