Re: [PATCH v3 15/19] vhost: postpone rings addresses translation

["Yao, Lei A" <lei.a.yao@intel.com>]

Hi, Maxime

> -----Original Message-----
> From: Yao, Lei A
> Sent: Friday, October 13, 2017 3:55 PM
> To: Maxime Coquelin <maxime.coquelin@redhat.com>; dev@dpdk.org;
> Horton, Remy <remy.horton@intel.com>; Bie, Tiwei <tiwei.bie@intel.com>;
> yliu@fridaylinux.org
> Cc: mst@redhat.com; jfreiman@redhat.com; vkaplans@redhat.com;
> jasowang@redhat.com
> Subject: RE: [dpdk-dev] [PATCH v3 15/19] vhost: postpone rings addresses
> translation
> 
> Hi, Maxime
> 
> > -----Original Message-----
> > From: Maxime Coquelin [mailto:maxime.coquelin@redhat.com]
> > Sent: Friday, October 13, 2017 3:32 PM
> > To: Yao, Lei A <lei.a.yao@intel.com>; dev@dpdk.org; Horton, Remy
> > <remy.horton@intel.com>; Bie, Tiwei <tiwei.bie@intel.com>;
> > yliu@fridaylinux.org
> > Cc: mst@redhat.com; jfreiman@redhat.com; vkaplans@redhat.com;
> > jasowang@redhat.com
> > Subject: Re: [dpdk-dev] [PATCH v3 15/19] vhost: postpone rings addresses
> > translation
> >
> > Hi Lei,
> >
> > On 10/13/2017 03:47 AM, Yao, Lei A wrote:
> > > Hi, Maxime
> > >
> > > After this commit, vhost/virtio loopback test will fail when
> > > use the CPU on socket 1.
> > > Error message like following during initialize:
> > > VHOST_CONFIG: vring kick idx:0 file:20
> > > VHOST_CONFIG: reallocate vq from 0 to 1 node
> > > VHOST_CONFIG: reallocate dev from 0 to 1 node
> > > VHOST_CONFIG: (0) failed to find avail ring address.
> > > VHOST_CONFIG: read message VHOST_USER_SET_VRING_NUM
> > > VHOST_CONFIG: read message VHOST_USER_SET_VRING_BASE
> > > VHOST_CONFIG: read message VHOST_USER_SET_VRING_ADDR
> > > VHOST_CONFIG: read message VHOST_USER_SET_VRING_KICK
> > > VHOST_CONFIG: vring kick idx:1 file:21
> > > VHOST_CONFIG: reallocate vq from 0 to 1 node
> > > VHOST_CONFIG: (0) failed to find avail ring address.
> > >
> > > But if use CPU on socket 0. It still can work. Could you have a check on
> > > this? Thanks a lot!
> >
> > Thanks for reporting the issue. It seems addr pointer still points to
> > the old structure after the reallocation. This patch should fix the
> > issue:
> > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> > index 9acac6125..2416a0061 100644
> > --- a/lib/librte_vhost/vhost_user.c
> > +++ b/lib/librte_vhost/vhost_user.c
> > @@ -417,6 +417,7 @@ translate_ring_addresses(struct virtio_net *dev, int
> > vq_index)
> >
> >          dev = numa_realloc(dev, vq_index);
> >          vq = dev->virtqueue[vq_index];
> > +       addr = &vq->ring_addrs;
> >
> >          vq->avail = (struct vring_avail *)(uintptr_t)ring_addr_to_vva(dev,
> >                          vq, addr->avail_user_addr, sizeof(struct
> > vring_avail));
> >
> > I only have access to single-socket machines at the moment, so I cannot
> > reproduce the issue.
> > Can you have a try?
> With your new patch, it can work on socket 1 now. Thanks.
> 
I find another issue with this patch when I use V17.11-rc1.
It will break the connection between vhost and virtio-net in VM.
The link status of vhost-user port is always down.
But virtio-pmd driver is still ok. 

My qemu version: 2.5
Guest OS: Ubuntu 16.04
Guest kernel: 4.4.0

Could you have a check on this issue? Thanks a lot!

BRs
Lei

> >
> > Thanks,
> > Maxime
> >
> > > Following is my cmd:
> > > Vhost: testpmd -n 4 -c 0x3000000 --socket-mem 1024,1024 --file-
> > prefix=vhost \
> > >                  --vdev 'net_vhost0,iface=vhost-net,queues=1,client=0' -- -i
> > > Virtio-user: testpmd -n 4 -c 0xc00000 --socket-mem 1024,1024 --no-pci --
> > file-prefix=virtio \
> > >                         --
> vdev=net_virtio_user0,mac=00:01:02:03:04:05,path=./vhost-
> > net \
> > >                          -- -i --txqflags=0xf01 --disable-hw-vlan-filter
> > >
> > > BRs
> > > Lei
> > >
> > >> -----Original Message-----
> > >> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Maxime
> > Coquelin
> > >> Sent: Thursday, October 5, 2017 4:36 PM
> > >> To: dev@dpdk.org; Horton, Remy <remy.horton@intel.com>; Bie, Tiwei
> > >> <tiwei.bie@intel.com>; yliu@fridaylinux.org
> > >> Cc: mst@redhat.com; jfreiman@redhat.com; vkaplans@redhat.com;
> > >> jasowang@redhat.com; Maxime Coquelin
> > <maxime.coquelin@redhat.com>
> > >> Subject: [dpdk-dev] [PATCH v3 15/19] vhost: postpone rings addresses
> > >> translation
> > >>
> > >> This patch postpones rings addresses translations and checks, as
> > >> addresses sent by the master shuld not be interpreted as long as
> > >> ring is not started and enabled[0].
> > >>
> > >> When protocol features aren't negotiated, the ring is started in
> > >> enabled state, so the addresses translations are postponed to
> > >> vhost_user_set_vring_kick().
> > >> Otherwise, it is postponed to when ring is enabled, in
> > >> vhost_user_set_vring_enable().
> > >>
> > >> [0]: http://lists.nongnu.org/archive/html/qemu-devel/2017-
> > >> 05/msg04355.html
> > >>
> > >> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> > >> ---
> > >>   lib/librte_vhost/vhost.h      |  1 +
> > >>   lib/librte_vhost/vhost_user.c | 69
> > >> ++++++++++++++++++++++++++++++++++---------
> > >>   2 files changed, 56 insertions(+), 14 deletions(-)
> > >>
> > >> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
> > >> index 79351c66f..903da5db5 100644
> > >> --- a/lib/librte_vhost/vhost.h
> > >> +++ b/lib/librte_vhost/vhost.h
> > >> @@ -125,6 +125,7 @@ struct vhost_virtqueue {
> > >>
> > >>   	struct vring_used_elem  *shadow_used_ring;
> > >>   	uint16_t                shadow_used_idx;
> > >> +	struct vhost_vring_addr ring_addrs;
> > >>
> > >>   	struct batch_copy_elem	*batch_copy_elems;
> > >>   	uint16_t		batch_copy_nb_elems;
> > >> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> > >> index f495dd36e..319867c65 100644
> > >> --- a/lib/librte_vhost/vhost_user.c
> > >> +++ b/lib/librte_vhost/vhost_user.c
> > >> @@ -356,6 +356,7 @@ static int
> > >>   vhost_user_set_vring_addr(struct virtio_net *dev, VhostUserMsg
> *msg)
> > >>   {
> > >>   	struct vhost_virtqueue *vq;
> > >> +	struct vhost_vring_addr *addr = &msg->payload.addr;
> > >>
> > >>   	if (dev->mem == NULL)
> > >>   		return -1;
> > >> @@ -363,35 +364,50 @@ vhost_user_set_vring_addr(struct virtio_net
> > *dev,
> > >> VhostUserMsg *msg)
> > >>   	/* addr->index refers to the queue index. The txq 1, rxq is 0. */
> > >>   	vq = dev->virtqueue[msg->payload.addr.index];
> > >>
> > >> +	/*
> > >> +	 * Rings addresses should not be interpreted as long as the ring is not
> > >> +	 * started and enabled
> > >> +	 */
> > >> +	memcpy(&vq->ring_addrs, addr, sizeof(*addr));
> > >> +
> > >> +	return 0;
> > >> +}
> > >> +
> > >> +static struct virtio_net *translate_ring_addresses(struct virtio_net
> *dev,
> > >> +		int vq_index)
> > >> +{
> > >> +	struct vhost_virtqueue *vq = dev->virtqueue[vq_index];
> > >> +	struct vhost_vring_addr *addr = &vq->ring_addrs;
> > >> +
> > >>   	/* The addresses are converted from QEMU virtual to Vhost virtual.
> > >> */
> > >>   	vq->desc = (struct vring_desc *)(uintptr_t)qva_to_vva(dev,
> > >> -			msg->payload.addr.desc_user_addr);
> > >> +			addr->desc_user_addr);
> > >>   	if (vq->desc == 0) {
> > >>   		RTE_LOG(ERR, VHOST_CONFIG,
> > >>   			"(%d) failed to find desc ring address.\n",
> > >>   			dev->vid);
> > >> -		return -1;
> > >> +		return NULL;
> > >>   	}
> > >>
> > >> -	dev = numa_realloc(dev, msg->payload.addr.index);
> > >> -	vq = dev->virtqueue[msg->payload.addr.index];
> > >> +	dev = numa_realloc(dev, vq_index);
> > >> +	vq = dev->virtqueue[vq_index];
> > >>
> > >>   	vq->avail = (struct vring_avail *)(uintptr_t)qva_to_vva(dev,
> > >> -			msg->payload.addr.avail_user_addr);
> > >> +			addr->avail_user_addr);
> > >>   	if (vq->avail == 0) {
> > >>   		RTE_LOG(ERR, VHOST_CONFIG,
> > >>   			"(%d) failed to find avail ring address.\n",
> > >>   			dev->vid);
> > >> -		return -1;
> > >> +		return NULL;
> > >>   	}
> > >>
> > >>   	vq->used = (struct vring_used *)(uintptr_t)qva_to_vva(dev,
> > >> -			msg->payload.addr.used_user_addr);
> > >> +			addr->used_user_addr);
> > >>   	if (vq->used == 0) {
> > >>   		RTE_LOG(ERR, VHOST_CONFIG,
> > >>   			"(%d) failed to find used ring address.\n",
> > >>   			dev->vid);
> > >> -		return -1;
> > >> +		return NULL;
> > >>   	}
> > >>
> > >>   	if (vq->last_used_idx != vq->used->idx) {
> > >> @@ -403,7 +419,7 @@ vhost_user_set_vring_addr(struct virtio_net
> *dev,
> > >> VhostUserMsg *msg)
> > >>   		vq->last_avail_idx = vq->used->idx;
> > >>   	}
> > >>
> > >> -	vq->log_guest_addr = msg->payload.addr.log_guest_addr;
> > >> +	vq->log_guest_addr = addr->log_guest_addr;
> > >>
> > >>   	LOG_DEBUG(VHOST_CONFIG, "(%d) mapped address desc: %p\n",
> > >>   			dev->vid, vq->desc);
> > >> @@ -414,7 +430,7 @@ vhost_user_set_vring_addr(struct virtio_net
> *dev,
> > >> VhostUserMsg *msg)
> > >>   	LOG_DEBUG(VHOST_CONFIG, "(%d) log_guest_addr: %" PRIx64 "\n",
> > >>   			dev->vid, vq->log_guest_addr);
> > >>
> > >> -	return 0;
> > >> +	return dev;
> > >>   }
> > >>
> > >>   /*
> > >> @@ -685,10 +701,11 @@ vhost_user_set_vring_call(struct virtio_net
> > *dev,
> > >> struct VhostUserMsg *pmsg)
> > >>   }
> > >>
> > >>   static void
> > >> -vhost_user_set_vring_kick(struct virtio_net *dev, struct
> VhostUserMsg
> > >> *pmsg)
> > >> +vhost_user_set_vring_kick(struct virtio_net **pdev, struct
> > VhostUserMsg
> > >> *pmsg)
> > >>   {
> > >>   	struct vhost_vring_file file;
> > >>   	struct vhost_virtqueue *vq;
> > >> +	struct virtio_net *dev = *pdev;
> > >>
> > >>   	file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
> > >>   	if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
> > >> @@ -698,6 +715,16 @@ vhost_user_set_vring_kick(struct virtio_net
> *dev,
> > >> struct VhostUserMsg *pmsg)
> > >>   	RTE_LOG(INFO, VHOST_CONFIG,
> > >>   		"vring kick idx:%d file:%d\n", file.index, file.fd);
> > >>
> > >> +	/*
> > >> +	 * Interpret ring addresses only when ring is started and enabled.
> > >> +	 * This is now if protocol features aren't supported.
> > >> +	 */
> > >> +	if (!(dev->features & (1ULL <<
> > >> VHOST_USER_F_PROTOCOL_FEATURES))) {
> > >> +		*pdev = dev = translate_ring_addresses(dev, file.index);
> > >> +		if (!dev)
> > >> +			return;
> > >> +	}
> > >> +
> > >>   	vq = dev->virtqueue[file.index];
> > >>
> > >>   	/*
> > >> @@ -778,15 +805,29 @@ vhost_user_get_vring_base(struct virtio_net
> > *dev,
> > >>    * enable the virtio queue pair.
> > >>    */
> > >>   static int
> > >> -vhost_user_set_vring_enable(struct virtio_net *dev,
> > >> +vhost_user_set_vring_enable(struct virtio_net **pdev,
> > >>   			    VhostUserMsg *msg)
> > >>   {
> > >> +	struct virtio_net *dev = *pdev;
> > >>   	int enable = (int)msg->payload.state.num;
> > >>
> > >>   	RTE_LOG(INFO, VHOST_CONFIG,
> > >>   		"set queue enable: %d to qp idx: %d\n",
> > >>   		enable, msg->payload.state.index);
> > >>
> > >> +	/*
> > >> +	 * Interpret ring addresses only when ring is started and enabled.
> > >> +	 * This is now if protocol features are supported.
> > >> +	 */
> > >> +	if (enable && (dev->features &
> > >> +				(1ULL <<
> > >> VHOST_USER_F_PROTOCOL_FEATURES))) {
> > >> +		dev = translate_ring_addresses(dev, msg-
> > >>> payload.state.index);
> > >> +		if (!dev)
> > >> +			return -1;
> > >> +
> > >> +		*pdev = dev;
> > >> +	}
> > >> +
> > >>   	if (dev->notify_ops->vring_state_changed)
> > >>   		dev->notify_ops->vring_state_changed(dev->vid,
> > >>   				msg->payload.state.index, enable);
> > >> @@ -1155,7 +1196,7 @@ vhost_user_msg_handler(int vid, int fd)
> > >>   		break;
> > >>
> > >>   	case VHOST_USER_SET_VRING_KICK:
> > >> -		vhost_user_set_vring_kick(dev, &msg);
> > >> +		vhost_user_set_vring_kick(&dev, &msg);
> > >>   		break;
> > >>   	case VHOST_USER_SET_VRING_CALL:
> > >>   		vhost_user_set_vring_call(dev, &msg);
> > >> @@ -1174,7 +1215,7 @@ vhost_user_msg_handler(int vid, int fd)
> > >>   		break;
> > >>
> > >>   	case VHOST_USER_SET_VRING_ENABLE:
> > >> -		vhost_user_set_vring_enable(dev, &msg);
> > >> +		vhost_user_set_vring_enable(&dev, &msg);
> > >>   		break;
> > >>   	case VHOST_USER_SEND_RARP:
> > >>   		vhost_user_send_rarp(dev, &msg);
> > >> --
> > >> 2.13.6
> > >