Re: [dpdk-dev] [Suspected-Phishing][PATCH] net/vhost: add an API for get queue status

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

On 6/25/19 9:00 AM, Noa Ezra wrote:
> 
> 
>> -----Original Message-----
>> From: Maxime Coquelin [mailto:maxime.coquelin@redhat.com]
>> Sent: Monday, June 24, 2019 7:47 PM
>> To: Noa Ezra <noae@mellanox.com>; tiwei.bie@intel.com;
>> zhihong.wang@intel.com
>> Cc: Matan Azrad <matan@mellanox.com>; dev@dpdk.org
>> Subject: Re: [Suspected-Phishing][PATCH] net/vhost: add an API for get
>> queue status
>>
>>
>>
>> On 6/24/19 1:08 PM, Noa Ezra wrote:
>>> Hi,
>>> What do you say about this patch?
>>
>> I acknowledge we miss a way to get the queue state, but I don't like
>> introducing new APIs for PMD drivers.
>>
>> I looked at ethdev ops on Friday, but it seems no one currently available can
>> do the job.
>>
>> I would suggest to create new ethdev ops like:
>> .get_tx_queue_state(int port_id, int queue_id) .get_rx_queue_state(int
>> port_id, int queue_id)
>>
>> That would return wether the queue is enabled or not.
>>
>> What do you think?
> 
> I understand what you say about not having new APIs in the PMD, but I see that there are already APIs in the vhost pmd.

Indeed, and I hope we can get rid off them one day.

> rte_eth_vhost_get_queue_event allows to get the queue_state asynchronously, so it sounds reasonable to add an API that allows to get the queue_state synchronously.

I think we can get rid off rte_eth_vhost_get_queue_event easily.
Maybe we can even just drop it if we implement the new ethdev ops.

> Maybe in the future we can create new ethdev ops like you suggested and remove both APIs for getting queue_state.
> Currently I don’t have the resources for such implementation and we really need the ability to get queue_state.

It is anyway too late for v19.08, as the proposal deadline is over 3
weeks now. I will only accept fixes or small patches that have limited
impact.

Here, the patch is adding a new API, which is significant.
And with the new API stability rules that is being put in place, it may
imply that we'll need to support it for more than 2 years.

So for v19.11, if you think you don't have the bandwidth, maybe I can
try to do it. I really prefer that than having an API already deprecated
when merged in master.

Thanks,
Maxime
> Thanks,
> Noa.
> 
> 
>> Thanks,
>> Maxime
>>> Thanks,
>>> Noa.
>>>
>>>> -----Original Message-----
>>>> From: Noa Ezra [mailto:noae@mellanox.com]
>>>> Sent: Wednesday, June 19, 2019 9:15 AM
>>>> To: maxime.coquelin@redhat.com
>>>> Cc: Matan Azrad <matan@mellanox.com>; dev@dpdk.org; Noa Ezra
>>>> <noae@mellanox.com>
>>>> Subject: [Suspected-Phishing][PATCH] net/vhost: add an API for get
>>>> queue status
>>>>
>>>> Add an API that returns queue status for requested queue in the port.
>>>> The queue's status can be changed before the user has signed for the
>>>> queue state event interrupt. In this case the user can't know the
>>>> current queue's status. This API returns the current status.
>>>>
>>>> Signed-off-by: Noa Ezra <noae@mellanox.com>
>>>> Reviewed-by: Matan Azrad <matan@mellanox.com>
>>>> ---
>>>>    drivers/net/vhost/rte_eth_vhost.c           | 47
>>>> +++++++++++++++++++++++++++++
>>>>    drivers/net/vhost/rte_eth_vhost.h           | 18 +++++++++++
>>>>    drivers/net/vhost/rte_pmd_vhost_version.map |  6 ++++
>>>>    3 files changed, 71 insertions(+)
>>>>
>>>> diff --git a/drivers/net/vhost/rte_eth_vhost.c
>>>> b/drivers/net/vhost/rte_eth_vhost.c
>>>> index 9a54020..cad1e5c 100644
>>>> --- a/drivers/net/vhost/rte_eth_vhost.c
>>>> +++ b/drivers/net/vhost/rte_eth_vhost.c
>>>> @@ -855,6 +855,7 @@ struct vhost_xstats_name_off {
>>>>    	/* won't be NULL */
>>>>    	state = vring_states[eth_dev->data->port_id];
>>>>    	rte_spinlock_lock(&state->lock);
>>>> +
>>>>    	state->cur[vring] = enable;
>>>>    	state->max_vring = RTE_MAX(vring, state->max_vring);
>>>>    	rte_spinlock_unlock(&state->lock);
>>>> @@ -874,6 +875,52 @@ struct vhost_xstats_name_off {  };
>>>>
>>>>    int
>>>> +rte_eth_vhost_get_queue_status(uint16_t port_id, bool rx, uint16_t
>>>> queue_id,
>>>> +		bool *queue_status)
>>>> +{
>>>> +	struct rte_vhost_vring_state *state;
>>>> +	struct internal_list *list;
>>>> +	struct rte_eth_dev *eth_dev;
>>>> +	int found = 0;
>>>> +	uint16_t nb_q = 0;
>>>> +
>>>> +	if (port_id >= RTE_MAX_ETHPORTS) {
>>>> +		VHOST_LOG(ERR, "Invalid port id\n");
>>>> +		return -1;
>>>> +	}
>>>> +	TAILQ_FOREACH(list, &internal_list, next) {
>>>> +		eth_dev = list->eth_dev;
>>>> +		if (eth_dev->data->port_id == port_id) {
>>>> +			nb_q = rx ? eth_dev->data->nb_rx_queues :
>>>> +					eth_dev->data->nb_tx_queues;
>>>> +			found = 1;
>>>> +			break;
>>>> +		}
>>>> +	}
>>>> +	if (!found) {
>>>> +		VHOST_LOG(ERR, "No device found for port id %u\n",
>>>> port_id);
>>>> +		return -1;
>>>> +	}
>>>> +	if (queue_id >= nb_q) {
>>>> +		VHOST_LOG(ERR, "Invalid queue id\n");
>>>> +		return -1;
>>>> +	}
>>>> +
>>>> +	state = vring_states[port_id];
>>>> +	if (!state) {
>>>> +		VHOST_LOG(ERR, "Unused port\n");
>>>> +		return -1;
>>>> +	}
>>>> +
>>>> +	rte_spinlock_lock(&state->lock);
>>>> +	*queue_status = rx ? state->cur[queue_id * 2 + 1] :
>>>> +			state->cur[queue_id * 2];
>>>> +	rte_spinlock_unlock(&state->lock);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +int
>>>>    rte_eth_vhost_get_queue_event(uint16_t port_id,
>>>>    		struct rte_eth_vhost_queue_event *event)  { diff --git
>>>> a/drivers/net/vhost/rte_eth_vhost.h
>>>> b/drivers/net/vhost/rte_eth_vhost.h
>>>> index 0e68b9f..1e65c69 100644
>>>> --- a/drivers/net/vhost/rte_eth_vhost.h
>>>> +++ b/drivers/net/vhost/rte_eth_vhost.h
>>>> @@ -44,6 +44,24 @@ int rte_eth_vhost_get_queue_event(uint16_t
>> port_id,
>>>>    		struct rte_eth_vhost_queue_event *event);
>>>>
>>>>    /**
>>>> + * Get queue status for specific queue in the port.
>>>> + *
>>>> + * @param[in] port_id
>>>> + *  Port id.
>>>> + * @param[in] rx
>>>> + *  True is rx, False if tx
>>>> + * @paran[in] queue_id
>>>> + *  Queue_id
>>>> + * @param[out] queue_status
>>>> + *  Pointer to a boolean, True is enable, False if disable.
>>>> + * @return
>>>> + *  - On success, zero, queue_status is updated.
>>>> + *  - On failure, a negative value, queue_status is not updated.
>>>> + */
>>>> +int rte_eth_vhost_get_queue_status(uint16_t port_id, bool rx,
>>>> +uint16_t
>>>> queue_id,
>>>> +		bool *queue_status);
>>>> +
>>>> +/**
>>>>     * Get the 'vid' value associated with the specified port.
>>>>     *
>>>>     * @return
>>>> diff --git a/drivers/net/vhost/rte_pmd_vhost_version.map
>>>> b/drivers/net/vhost/rte_pmd_vhost_version.map
>>>> index 695db85..1eabfd2 100644
>>>> --- a/drivers/net/vhost/rte_pmd_vhost_version.map
>>>> +++ b/drivers/net/vhost/rte_pmd_vhost_version.map
>>>> @@ -11,3 +11,9 @@ DPDK_16.11 {
>>>>
>>>>    	rte_eth_vhost_get_vid_from_port_id;
>>>>    };
>>>> +
>>>> +DPDK_19.08 {
>>>> +	global:
>>>> +
>>>> +	rte_eth_vhost_get_queue_status;
>>>> +};
>>>> --
>>>> 1.8.3.1
>>>