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

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

On 10/13/2017 09:55 AM, Yao, Lei A wrote:
> 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.

Great, thanks for testing. I'll post the patch today.

Thanks,
Maxime
>>
>> 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
>>>