[EXT] Re: [PATCH 2/4] node: add a node to receive pkts from kernel

[Vamsi Krishna Attunuru]

> -----Original Message-----
> From: Jerin Jacob <jerinjacobk at gmail.com>
> Sent: Monday, May 29, 2023 11:10 PM
> To: Vamsi Krishna Attunuru <vattunuru at marvell.com>
> Cc: dev at dpdk.org; Jerin Jacob Kollanukkaran <jerinj at marvell.com>; Nithin
> Kumar Dabilpuram <ndabilpuram at marvell.com>
> Subject: [EXT] Re: [PATCH 2/4] node: add a node to receive pkts from kernel
> 
> External Email
> 
> ----------------------------------------------------------------------
> On Fri, Apr 21, 2023 at 11:33 AM Vamsi Attunuru <vattunuru at marvell.com>
> wrote:
> >
> > Patch adds a node to receive packets from kernel over a raw socket.
> 
> Subjection suggestion: node/kernel_rx: support receving packet from kernel
> >
> > Signed-off-by: Vamsi Attunuru <vattunuru at marvell.com>
> > ---
> >  doc/guides/prog_guide/graph_lib.rst |   7 +
> >  lib/node/kernel_recv.c              | 277 ++++++++++++++++++++++++++++
> >  lib/node/kernel_recv_priv.h         |  74 ++++++++
> >  lib/node/meson.build                |   1 +
> >  4 files changed, 359 insertions(+)
> >
> > diff --git a/doc/guides/prog_guide/graph_lib.rst
> > b/doc/guides/prog_guide/graph_lib.rst
> > index b3b5b14827..1057f16de8 100644
> > --- a/doc/guides/prog_guide/graph_lib.rst
> > +++ b/doc/guides/prog_guide/graph_lib.rst
> > @@ -402,3 +402,10 @@ on the raw socket.
> >
> >  Aftering sending the burst of packets to kernel, this node redirects
> > the same  objects to pkt_drop node to free up the packet buffers.
> > +
> > +kernel_recv
> 
> Better to change node name to kernel_rx
> 
> > +~~~~~~~~~~~
> > +This node receives packets from kernel over a raw socket interface.
> > +Uses ``poll`` function to poll on the socket fd for ``POLLIN`` events
> > +to read the packets from raw socket to stream buffer and does
> > +``rte_node_next_stream_move()`` when there are received packets.
> 
> You can tell typical use case for punt and kernel_tx node. i.e expection path
> handling.
> Also, may consider chnage to kernel_tx  for punt node.
> 
ack
> 
> > diff --git a/lib/node/kernel_recv.c b/lib/node/kernel_recv.c new file
> > mode 100644 index 0000000000..361dcc3b5f
> > --- /dev/null
> > +++ b/lib/node/kernel_recv.c
> > @@ -0,0 +1,277 @@
> > +/* SPDX-License-Identifier: BSD-3-Clause
> > + * Copyright(C) 2023 Marvell International Ltd.
> > + */
> > +
> > +#include <fcntl.h>
> > +#include <poll.h>
> > +#include <stdlib.h>
> > +#include <sys/ioctl.h>
> > +#include <sys/socket.h>
> > +#include <unistd.h>
> > +
> > +#include <rte_debug.h>
> > +#include <rte_ethdev.h>
> > +#include <rte_graph.h>
> > +#include <rte_graph_worker.h>
> > +#include <rte_ip.h>
> > +#include <rte_malloc.h>
> > +#include <rte_mbuf.h>
> > +#include <rte_mempool.h>
> > +#include <rte_net.h>
> > +
> > +#include "ethdev_rx_priv.h"
> > +#include "kernel_recv_priv.h"
> > +#include "node_private.h"
> > +
> > +static struct kernel_recv_node_main kernel_recv_main;
> 
> Try to remove global varible.
> 
> > +#ifndef __INCLUDE_KERNEL_RECV_PRIV_H__
> 
> No need to add INCLUDE
> 
> > +#define __INCLUDE_KERNEL_RECV_PRIV_H__
> > +
> > +#define KERN_RECV_CACHE_COUNT 64
> > +
> > +typedef struct kernel_recv_info {
> > +       struct rte_mbuf *rx_bufs[KERN_RECV_CACHE_COUNT];
> > +       uint16_t cls_next;
> > +       uint16_t idx;
> > +       uint16_t cnt;
> > +       int sock;
> > +} kernel_recv_info_t;
> > +
> > +/**
> > + * @internal
> > + *
> > + * Kernel Recv node context structure.
> 
> Across the patch series, no need for Doxgen comments for internal
> functions.
Sure Jerin.