On Thu, 24 Sep 2015 18:35:37 +0000 "Xie, Huawei" <huawei.xie at intel.com> wrote:
> On 9/25/2015 12:36 AM, Stephen Hemminger wrote: > > On Thu, 24 Sep 2015 07:30:41 +0000 > > "Xie, Huawei" <huawei.xie at intel.com> wrote: > > > >> On 9/21/2015 11:39 AM, Xie, Huawei wrote: > >> vring_size calculation should consider both used_event_idx at the tail > >> of avail ring and avail_event_idx at the tail of used ring. > >> Will merge those two fixes and send a new patch. > >>> used event idx is put at the end of available ring. It isn't taken into > >>> account > >>> when we calculate the address of used ring. Fortunately, it doesn't > >>> introduce > >>> the bug with fixed queue number 256 and 4KB alignment. > >>> > >>> Signed-off-by: hxie5 <huawei.xie at intel.com> > >>> --- > >>> drivers/net/virtio/virtio_ring.h | 2 +- > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>> > >>> diff --git a/drivers/net/virtio/virtio_ring.h > >>> b/drivers/net/virtio/virtio_ring.h > >>> index a16c499..92e430d 100644 > >>> --- a/drivers/net/virtio/virtio_ring.h > >>> +++ b/drivers/net/virtio/virtio_ring.h > >>> @@ -145,7 +145,7 @@ vring_init(struct vring *vr, unsigned int num, > >>> uint8_t *p, > >>> vr->avail = (struct vring_avail *) (p + > >>> num * sizeof(struct vring_desc)); > >>> vr->used = (void *) > >>> - RTE_ALIGN_CEIL((uintptr_t)(&vr->avail->ring[num]), align); > >>> + RTE_ALIGN_CEIL((uintptr_t)(&vr->avail->ring[num + 1]), align); > >>> } > >>> > >>> /* > > Why aren't we just using the standard Linux includes for this? > > See <linux/virtio_ring.h> and the function vring_init() > > > > Keeping parallel copies of headers is prone to failures. > Agree. > Using standard Linux includes then at least we don't need to redefine > the feature and other related MACRO. > This applies to vhost as well. > For vring, vring_init, we could also reuse the linux implementation > unless we have strong reason to define our own structure. > One reason was to support both FreeBSD and Linux. FreeBSD should have > its own header file. To avoid the case they have different vring > structure or VIRTIO_F_xx macro name, they are redefined here. > > > > The Linux headers for virtio are explictly BSD licensed. You could at least just have a local copy of same code.
