From: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
To: Stephen Hemminger <stephen@networkplumber.org>,
"dev@dpdk.org" <dev@dpdk.org>
Cc: nd <nd@arm.com>, nd <nd@arm.com>
Subject: RE: unnecessary rx callbacks when zero packets
Date: Sun, 7 Jan 2024 20:57:07 +0000 [thread overview]
Message-ID: <DBAPR08MB58143669AD459E90DED7E42598642@DBAPR08MB5814.eurprd08.prod.outlook.com> (raw)
In-Reply-To: <20240107093721.512f1365@hermes.local>
> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Sunday, January 7, 2024 11:37 AM
> To: dev@dpdk.org
> Subject: unnecessary rx callbacks when zero packets
>
> I noticed while looking at packet capture that currently the receive callbacks
> get called even if there are no packets. This seems unnecessary since if nb_rx is
> zero, then there are no packets to look at. My one concern is that an
> application could be using callbacks as some form of scheduling mechanism
> which would be broken.
Is it possible that the call back functions are maintaining statistics on zero packet polls?
>
> The change would be:
>
>
> diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h index
> 21e3a21903ec..f64bf977c46e 100644
> --- a/lib/ethdev/rte_ethdev.h
> +++ b/lib/ethdev/rte_ethdev.h
> @@ -6077,7 +6077,7 @@ rte_eth_rx_burst(uint16_t port_id, uint16_t
> queue_id,
> nb_rx = p->rx_pkt_burst(qd, rx_pkts, nb_pkts);
>
> #ifdef RTE_ETHDEV_RXTX_CALLBACKS
> - {
> + if (nb_rx > 0) {
> void *cb;
>
> /* rte_memory_order_release memory order was used when the
next prev parent reply other threads:[~2024-01-07 20:57 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-07 17:37 Stephen Hemminger
2024-01-07 20:57 ` Honnappa Nagarahalli [this message]
2024-01-08 10:19 ` Morten Brørup
2024-01-08 15:20 ` Konstantin Ananyev
2024-01-09 11:28 ` Ferruh Yigit
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