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

[Maxime Coquelin <maxime.coquelin@redhat.com>]

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?

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
>