On Tue, Aug 27, 2024 at 01:26:37PM -0700, Jakub Kicinski wrote:
> On Fri, 23 Aug 2024 02:44:29 -0700 Souradeep Chakrabarti wrote:
> > @@ -2023,14 +2024,17 @@ static void mana_destroy_rxq(struct mana_port_context *apc,
> >
> > napi = &rxq->rx_cq.napi;
> >
> > - if (validate_state)
> > - napi_synchronize(napi);
> > + if (napi->dev == apc->ndev) {
> >
> > - napi_disable(napi);
> > + if (validate_state)
> > + napi_synchronize(napi);
> >
> > - xdp_rxq_info_unreg(&rxq->xdp_rxq);
> > + napi_disable(napi);
> >
> > - netif_napi_del(napi);
> > + netif_napi_del(napi);
> > + }
> > +
> > + xdp_rxq_info_unreg(&rxq->xdp_rxq);
>
> Please don't use internal core state as a crutch for your cleanup.
>
> IDK what "validate_state" stands for, but it gives you all the info you
> need on Rx. On Rx NAPI registration happens as the last stage of rxq
> activation, once nothing can fail. And the "cleanup" path calls destroy
> with validate_state=false. The only other caller passes true.
>
> So you can rewrite this as:
>
> if (validate_state) { /* rename it maybe? */
> napi_disable(napi);
> ...
> }
> xdp_rxq_info_unreg(&rxq->xdp_rxq);
>
> You can take similar approach with Tx. Pass a bool which tells the
> destroy function whether NAPI has been registered.
Thanks Jakub for the suggestion. I have changed the implementation
in the V3. I have added a new txq and rxq structure attribute to check
that per queue napi is initialized.
The use of a local flag like validate_state will not be possible with
current design of txq destroy function, as it uses the hole vport
and loops for all the queues for that port.
-
Souradeep
> --
> pw-bot: cr
