> -----Original Message-----
> From: Zhang, Qi Z
> Sent: Thursday, March 15, 2018 3:09 PM
> To: Ananyev, Konstantin <konstantin.anan...@intel.com>; tho...@monjalon.net
> Cc: dev@dpdk.org; Xing, Beilei <beilei.x...@intel.com>; Wu, Jingjing
> <jingjing...@intel.com>; Lu, Wenzhuo <wenzhuo...@intel.com>
> Subject: RE: [dpdk-dev] [PATCH v2 1/4] ether: support deferred queue setup
>
>
>
> > -----Original Message-----
> > From: Ananyev, Konstantin
> > Sent: Thursday, March 15, 2018 9:17 PM
> > To: Zhang, Qi Z <qi.z.zh...@intel.com>; tho...@monjalon.net
> > Cc: dev@dpdk.org; Xing, Beilei <beilei.x...@intel.com>; Wu, Jingjing
> > <jingjing...@intel.com>; Lu, Wenzhuo <wenzhuo...@intel.com>
> > Subject: RE: [dpdk-dev] [PATCH v2 1/4] ether: support deferred queue setup
> >
> > Hi Qi,
> >
> > > -----Original Message-----
> > > From: Zhang, Qi Z
> > > Sent: Thursday, March 15, 2018 3:14 AM
> > > To: Ananyev, Konstantin <konstantin.anan...@intel.com>;
> > > tho...@monjalon.net
> > > Cc: dev@dpdk.org; Xing, Beilei <beilei.x...@intel.com>; Wu, Jingjing
> > > <jingjing...@intel.com>; Lu, Wenzhuo <wenzhuo...@intel.com>
> > > Subject: RE: [dpdk-dev] [PATCH v2 1/4] ether: support deferred queue
> > > setup
> > >
> > > Hi Konstantin:
> > >
> > > > -----Original Message-----
> > > > From: Ananyev, Konstantin
> > > > Sent: Wednesday, March 14, 2018 8:32 PM
> > > > To: Zhang, Qi Z <qi.z.zh...@intel.com>; tho...@monjalon.net
> > > > Cc: dev@dpdk.org; Xing, Beilei <beilei.x...@intel.com>; Wu, Jingjing
> > > > <jingjing...@intel.com>; Lu, Wenzhuo <wenzhuo...@intel.com>; Zhang,
> > > > Qi Z <qi.z.zh...@intel.com>
> > > > Subject: RE: [dpdk-dev] [PATCH v2 1/4] ether: support deferred queue
> > > > setup
> > > >
> > > > Hi Qi,
> > > >
> > > > >
> > > > > The patch let etherdev driver expose the capability flag through
> > > > > rte_eth_dev_info_get when it support deferred queue configuraiton,
> > > > > then base on the flag rte_eth_[rx|tx]_queue_setup could decide
> > > > > continue to setup the queue or just return fail when device
> > > > > already started.
> > > > >
> > > > > Signed-off-by: Qi Zhang <qi.z.zh...@intel.com>
> > > > > ---
> > > > > doc/guides/nics/features.rst | 8 ++++++++
> > > > > lib/librte_ether/rte_ethdev.c | 30 ++++++++++++++++++------------
> > > > > lib/librte_ether/rte_ethdev.h | 11 +++++++++++
> > > > > 3 files changed, 37 insertions(+), 12 deletions(-)
> > > > >
> > > > > diff --git a/doc/guides/nics/features.rst
> > > > > b/doc/guides/nics/features.rst index 1b4fb979f..36ad21a1f 100644
> > > > > --- a/doc/guides/nics/features.rst
> > > > > +++ b/doc/guides/nics/features.rst
> > > > > @@ -892,7 +892,15 @@ Documentation describes performance
> > values.
> > > > >
> > > > > See ``dpdk.org/doc/perf/*``.
> > > > >
> > > > > +.. _nic_features_queue_deferred_setup_capabilities:
> > > > >
> > > > > +Queue deferred setup capabilities
> > > > > +---------------------------------
> > > > > +
> > > > > +Supports queue setup / release after device started.
> > > > > +
> > > > > +* **[provides] rte_eth_dev_info**:
> > > > >
> > > >
> > ``deferred_queue_config_capa:DEV_DEFERRED_RX_QUEUE_SETUP,DEV_DEFE
> > > > RRED_
> > > > > TX_QUEUE_SETUP,DEV_DEFERRED_RX_QUEUE_RELE
> > > > > ASE,DEV_DEFERRED_TX_QUEUE_RELEASE``.
> > > > > +* **[related] API**: ``rte_eth_dev_info_get()``.
> > > > >
> > > > > .. _nic_features_other:
> > > > >
> > > > > diff --git a/lib/librte_ether/rte_ethdev.c
> > > > > b/lib/librte_ether/rte_ethdev.c index a6ce2a5ba..6c906c4df 100644
> > > > > --- a/lib/librte_ether/rte_ethdev.c
> > > > > +++ b/lib/librte_ether/rte_ethdev.c
> > > > > @@ -1425,12 +1425,6 @@ rte_eth_rx_queue_setup(uint16_t port_id,
> > > > uint16_t rx_queue_id,
> > > > > return -EINVAL;
> > > > > }
> > > > >
> > > > > - if (dev->data->dev_started) {
> > > > > - RTE_PMD_DEBUG_TRACE(
> > > > > - "port %d must be stopped to allow configuration\n",
> > port_id);
> > > > > - return -EBUSY;
> > > > > - }
> > > > > -
> > > > > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_infos_get,
> > > > -ENOTSUP);
> > > > > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_setup,
> > > > -ENOTSUP);
> > > > >
> > > > > @@ -1474,10 +1468,19 @@ rte_eth_rx_queue_setup(uint16_t
> > port_id,
> > > > uint16_t rx_queue_id,
> > > > > return -EINVAL;
> > > > > }
> > > > >
> > > > > + if (dev->data->dev_started &&
> > > > > + !(dev_info.deferred_queue_config_capa &
> > > > > + DEV_DEFERRED_RX_QUEUE_SETUP))
> > > > > + return -EINVAL;
> > > > > +
> > > >
> > > > I think now you have to check here that the queue is stopped.
> > > > Otherwise you might attempt to reconfigure running queue.
> > >
> > > I'm not sure if it's necessary to let application use different API
> > > sequence
> > for a deferred configure and deferred re-configure.
> > > Can we just call dev_ops->rx_queue_stop before rx_queue_release here
> >
> > I don't follow you here.
> > Let say now inside queue_start() we do check:
> >
> > if (dev->data->rx_queue_state[rx_queue_id] !=
> > RTE_ETH_QUEUE_STATE_STOPPED)
> >
> > Right now it is not possible to call queue_setup() without dev_stop() before
> > it - that's why we have check if (dev->data->dev_started) in queue_setup()
> > right now.
> > Though with your patch it not the case anymore - user is able to call
> > queue_setup() without stopping the whole device.
> > But he still has to stop the queue.
>
> >
> > >
> > > >
> > > >
> > > > > rxq = dev->data->rx_queues;
> > > > > if (rxq[rx_queue_id]) {
> > > > >
> > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release,
> > > > > -ENOTSUP);
> > > >
> > > > I don't think it is *that* straightforward.
> > > > rx_queue_setup() parameters can imply different rx function (and
> > > > related dev
> > > > icesettings) that are already setuped by previous
> > queue_setup()/dev_start.
> > > > So I think you need to do one of 2 things:
> > > > 1. rework ethdev layer to introduce a separate rx function (and
> > > > related
> > > > settings) for each queue.
> > > > 2. at rx_queue_setup() if it is invoked after dev_start - check that
> > > > given queue settings wouldn't contradict with current device
> > > > settings (rx function, etc.).
> > > > If they do - return an error.
> > > Yes, I think what we have is option 2 here, the
> > > dev_ops->rx_queue_setup will return fail if conflict with previous
> > > setting
> >
> > Hmm and what makes you think that?
> > As I know it is not the case right now.
> > Let say I do:
> > ....
> > rx_queue_setup(port=0,queue=0, mp=mb_size_2048);
> > dev_start(port=0);
> > ...
> > rx_queue_setup(port=0,queue=1,mp=mb_size_1024);
> >
> > If current rx function doesn't support multi-segs then second
> > rx_queue_setup() should fail.
> > Though I don't think that would happen with the current implementation.
>
> Why you think that would not happen? dev_ops->rx_queue_setup can fail, right?
> I mean it's the responsibility of low level driver (i40e) to check the
> conflict with current implementation.
Yes it is responsibility if the PMD because only it knows its own logic of
rx/tx function selection.
But I don't see such changes in i40e in your patch series.
Probably I missed them?
> >
> > Same story for TX offloads, though it probably not that critical, as for
> > most
> > Intel PMDs HW TX offloads will become per port in 18.05.
> >
> > As I can see you do have either of these options implemented right now -
> > that's the problem.
> >
> > > I'm also thinking about option 1, the idea is to move per queue rx/tx
> > function into driver layer, so it will not break existing API.
> > >
> > > 1. driver can expose the capability like per_queue_rx or per_queue_tx
> > > 2. application can enable this capability by dev_config with
> > > rte_eth_conf 3, if per_queue_rx is not enable, nothing change, so we
> > > are at option 2 4. if per_queue_rx is enabled, driver will set
> > > rx_pkt_burst with a hook function which redirect to an function ptr in
> > > a per queue rx function tables ( I guess performance is impacted
> > > somehow, but this is the cost if you want different offload for
> > > different queue)
> >
> > I don't think we need to overcomplicate things here.
> > It should be transparent to the user - user just calls queue_setup() -
> > based on
> > its input parameters PMD selects a function that fits best.
> > Pretty much what we have right now, just possibly have an array of functions
> > (one per queue).
>
> If we don't introduce a new capability or something like, but just take per
> queue functions as default way,
> does that mean, we need to change all drivers to adapt this?
> Or do you mean below?
>
> If (dev->rx_pkt_burst)
> /* default way */
> else
> /* per queue function */
For me either way seems ok.
Second one probably a bit easier, as no changes from PMDs are required.
But again - might be even rte_ethdev layer can fill queue's rx_pkt_burst[] array
for the drivers that don't support it - just by copying dev->rx_pkt_burst into
it.
Konstantin
>
> Regards
> Qi
>
> >
> > >
> > > >
> > > > From my perspective - 1) is a better choice though it required more
> > > > work, and possibly ABI breakage.
> > > > I did some work in that direction as RFC:
> > > > http://dpdk.org/dev/patchwork/patch/31866/
> > >
> > > I will learn this, thanks for the heads up.
> > > >
> > > > 2) might be also possible, but looks a bit clumsy as
> > > > rx_queue_setup() might now fail even with valid parameters - all
> > > > depends on previous queue configurations.
> > > >
> > > > Same story applies for TX.
> > > >
> > > >
> > > > > + if (dev->data->dev_started &&
> > > > > + !(dev_info.deferred_queue_config_capa &
> > > > > + DEV_DEFERRED_RX_QUEUE_RELEASE))
> > > > > + return -EINVAL;
> > > > > (*dev->dev_ops->rx_queue_release)(rxq[rx_queue_id]);
> > > > > rxq[rx_queue_id] = NULL;
> > > > > }
> > > > > @@ -1573,12 +1576,6 @@ rte_eth_tx_queue_setup(uint16_t port_id,
> > > > uint16_t tx_queue_id,
> > > > > return -EINVAL;
> > > > > }
> > > > >
> > > > > - if (dev->data->dev_started) {
> > > > > - RTE_PMD_DEBUG_TRACE(
> > > > > - "port %d must be stopped to allow configuration\n",
> > port_id);
> > > > > - return -EBUSY;
> > > > > - }
> > > > > -
> > > > > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_infos_get,
> > > > -ENOTSUP);
> > > > > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_setup,
> > > > -ENOTSUP);
> > > > >
> > > > > @@ -1596,10 +1593,19 @@ rte_eth_tx_queue_setup(uint16_t
> > port_id,
> > > > uint16_t tx_queue_id,
> > > > > return -EINVAL;
> > > > > }
> > > > >
> > > > > + if (dev->data->dev_started &&
> > > > > + !(dev_info.deferred_queue_config_capa &
> > > > > + DEV_DEFERRED_TX_QUEUE_SETUP))
> > > > > + return -EINVAL;
> > > > > +
> > > > > txq = dev->data->tx_queues;
> > > > > if (txq[tx_queue_id]) {
> > > > >
> > RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_release,
> > > > > -ENOTSUP);
> > > > > + if (dev->data->dev_started &&
> > > > > + !(dev_info.deferred_queue_config_capa &
> > > > > + DEV_DEFERRED_TX_QUEUE_RELEASE))
> > > > > + return -EINVAL;
> > > > > (*dev->dev_ops->tx_queue_release)(txq[tx_queue_id]);
> > > > > txq[tx_queue_id] = NULL;
> > > > > }
> > > > > diff --git a/lib/librte_ether/rte_ethdev.h
> > > > > b/lib/librte_ether/rte_ethdev.h index 036153306..410e58c50 100644
> > > > > --- a/lib/librte_ether/rte_ethdev.h
> > > > > +++ b/lib/librte_ether/rte_ethdev.h
> > > > > @@ -981,6 +981,15 @@ struct rte_eth_conf {
> > > > > */
> > > > > #define DEV_TX_OFFLOAD_SECURITY 0x00020000
> > > > >
> > > > > +#define DEV_DEFERRED_RX_QUEUE_SETUP 0x00000001 /**<
> > Deferred
> > > > setup rx
> > > > > +queue */ #define DEV_DEFERRED_TX_QUEUE_SETUP 0x00000002
> > /**<
> > > > Deferred
> > > > > +setup tx queue */ #define DEV_DEFERRED_RX_QUEUE_RELEASE
> > > > 0x00000004
> > > > > +/**< Deferred release rx queue */ #define
> > > > > +DEV_DEFERRED_TX_QUEUE_RELEASE 0x00000008 /**< Deferred
> > release
> > > > tx
> > > > > +queue */
> > > > > +
> > > >
> > > > I don't think we do need flags for both setup a and release.
> > > > If runtime setup is supported - surely dynamic release should be
> > > > supported too.
> > > > Also probably RUNTIME_RX_QUEUE_SETUP sounds a bit better.
> > >
> > > Agree
> > >
> > > Thanks
> > > Qi
> > >
> > > >
> > > > Konstantin
> > > >
> > > > > /*
> > > > > * If new Tx offload capabilities are defined, they also must be
> > > > > * mentioned in rte_tx_offload_names in rte_ethdev.c file.
> > > > > @@ -1029,6 +1038,8 @@ struct rte_eth_dev_info {
> > > > > /** Configured number of rx/tx queues */
> > > > > uint16_t nb_rx_queues; /**< Number of RX queues. */
> > > > > uint16_t nb_tx_queues; /**< Number of TX queues. */
> > > > > + uint64_t deferred_queue_config_capa;
> > > > > + /**< queues can be setup/release after dev_start
> > > > > +(DEV_DEFERRED_). */
> > > > > };
> > > > >
> > > > > /**
> > > > > --
> > > > > 2.13.6
