-----Original Message----- > Date: Wed, 9 Aug 2017 19:24:30 +0000 > From: "Eads, Gage" <gage.e...@intel.com> > To: Jerin Jacob <jerin.ja...@caviumnetworks.com> > CC: "Rao, Nikhil" <nikhil....@intel.com>, "dev@dpdk.org" <dev@dpdk.org>, > "tho...@monjalon.net" <tho...@monjalon.net>, "Richardson, Bruce" > <bruce.richard...@intel.com>, "Van Haaren, Harry" > <harry.van.haa...@intel.com>, "hemant.agra...@nxp.com" > <hemant.agra...@nxp.com>, "nipun.gu...@nxp.com" <nipun.gu...@nxp.com>, > "Vangati, Narender" <narender.vang...@intel.com>, "Gujjar, Abhinandan S" > <abhinandan.guj...@intel.com> > Subject: RE: [PATCH 1/2] eventdev: add event adapter for ethernet Rx queues > > > > > > > > > > > > > > > > I don't think we can rely on there being another port available -- > > > > > a user may > > > > have configured the sw eventdev with all 64 ports, for instance. > > > > > > > > On that case, irrespective any scheme(callback vs non callback) the > > > > adapter creation would fail. Right? > > > > > > > > > What if the user is required to calculate cfg.nb_event_ports as a > > > > > function of > > > > the RX_ADAPTER_CAP_INBUILT_PORT capability (i.e. add a port if the > > > > capability is not set), such that a reconfigure is not required? > > > > > > > > We have only one NON INBUILT eventdev port per adapter. Right? i.e > > > > in the v1 spec it was rte_event_eth_rx_adapter_conf.event_port_id, > > > > How about it can be rte_event_port_count() + 1 ? Since we are NOT > > > > linking this port, the context call be kept in adapter itself. Right? > > > > > > It could be. Thinking on it some more, I'm a little concerned about doing > > configuration without the application's knowledge. Possible issues that > > could > > arise: > > > - The user later reconfigures the event device with fewer ports and > > > the adapter's port becomes invalid, or reconfigures it with more ports > > > and begins using the port the adapter is using > > > - rte_event_port_count() + 1 extends beyond the PMD's capabilities > > > (the sw PMD is hard-coded to support a max of 64 ports, for example) > > > > > > Having the user be responsible for the port configuration could avoid > > > these > > problems. Since the user needs to check the <eventdev, ethdev> pair's > > capabilities for the CAP_ADD_QUEUE anyway, they could also check for > > INBUILT_PORT and decide whether or not to request an additional port at > > eventdev configure time -- thereby ensuring they don't waste a port when > > using > > hardware with inbuilt ports. And this keeps the configuration code in one > > place > > (the app), rather than spread across the app, adapter, and potentially the > > conf_cb. > > > > OK.Sounds reasonable.May be we can push the responsibility to application.We > > could have a helper function using the proposed adapter API. That helper > > function would create the adapter based on the capability for the _default_ > > case. > > Applications free to use the raw adapter API to get more control if > > required. > > Otherwise we will duplicate the code in all the applications. > > > > Makes sense. Are you thinking the helper function would do stop + reconfig > with additional port + start + setup port, or just setup the port with an ID > the app supplies (only when a port is required, of course)? The second one > could be done with little additional code -- the app just needs to check if > an additional port is needed when configuring the eventdev, and another > helper function could take a list of <eventdev, ethdev> pairs and return true > if any don't have an inbuilt port.
I am in favor adding more logic in helper function(I believe, first one ) so that it will help application reuse the helper functions for the normal case.
