> -----Original Message-----
> From: Andrzej Ostruszka [C] <aostrus...@marvell.com>
> Sent: Friday, April 3, 2020 6:22 PM
> To: Vamsi Krishna Attunuru <vattun...@marvell.com>; dev@dpdk.org
> Cc: jerinjac...@gmail.com; bruce.richard...@intel.com;
> david.march...@redhat.com; gr...@u256.net; Jerin Jacob Kollanukkaran
> <jer...@marvell.com>; Pavan Nikhilesh Bhagavatula
> <pbhagavat...@marvell.com>; tho...@monjalon.net
> Subject: Re: [PATCH] [v1 1/1] examples/l2fwd: add cmdline option for
> forwarding port info
>
> On 4/3/20 5:30 AM, vattun...@marvell.com wrote:
> > From: Vamsi Attunuru <vattun...@marvell.com>
> >
> > Current l2fwd application configures adjacent ports as destination
> > ports for forwarding the traffic which is a kind of static mapping
> > that can not be altered by the command line options.
> >
> > Patch adds a config option to pass the forwarding port pair mapping as
> > a command line parameter which allows the user to pass required
> > forwarding port mapping.
> >
> > If no config argument is specified, destination port map is not
> > changed and traffic gets forwarded with existing mapping.
> >
> > When port pair mapping is passed in config option, destination port
> > map is configured and traffic gets forwarded accordingly.
> >
> > Ex: ./l2fwd -c 0xff -- -p 0x3f --config="(0,3)(1,4)(2,5)"
> >
> > With above config option, traffic received from portid = 0 gets
> > forwarded to port = 3 and vice versa, similarly traffic gets forwarded
> > on other port pairs (1,4) and (2,5).
> >
> > Signed-off-by: Vamsi Attunuru <vattun...@marvell.com>
> > ---
> > doc/guides/rel_notes/release_20_05.rst | 6 +
> > .../sample_app_ug/l2_forward_real_virtual.rst | 18 ++-
> > examples/l2fwd/main.c | 174
> > ++++++++++++++++++---
> > 3 files changed, 177 insertions(+), 21 deletions(-)
> >
> > diff --git a/doc/guides/rel_notes/release_20_05.rst
> > b/doc/guides/rel_notes/release_20_05.rst
> > index 000bbf5..645400b 100644
> > --- a/doc/guides/rel_notes/release_20_05.rst
> > +++ b/doc/guides/rel_notes/release_20_05.rst
> > @@ -62,6 +62,12 @@ New Features
> >
> > * Added support for matching on IPv4 Time To Live and IPv6 Hop Limit.
> >
> > +* **Added --config command line parameter to l2fwd example.**
> > +
> > + Added new command line option ``--config(port, port)[,(port,
> > + port)]`` to
>
> Maybe use the actual syntax with '=' or space after 'config'?
>
> > + pass forwarding port details.
> > + See the :doc:`doc/guides/sample_app_ug/l2_forward_real_virtual` for
> > + more details of this parameter usage.
> >
> > Removed Items
> > -------------
> > diff --git a/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
> > b/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
> > index 39d6b00..e708f88 100644
> > --- a/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
> > +++ b/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
> > @@ -91,7 +91,10 @@ The application requires a number of command line
> options:
> >
> > .. code-block:: console
> >
> > - ./build/l2fwd [EAL options] -- -p PORTMASK [-q NQ] --[no-]mac-updating
> > + ./build/l2fwd [EAL options] -- -p PORTMASK
> > + [-q NQ]
> > + --[no-]mac-updating
> > + --config(port, port)[,(port,
> > + port)]
>
> Ditto
>
> >
> > where,
> >
> > @@ -99,7 +102,10 @@ where,
> >
> > * q NQ: A number of queues (=ports) per lcore (default is 1)
> >
> > -* --[no-]mac-updating: Enable or disable MAC addresses updating
> (enabled by default).
> > +* --[no-]mac-updating: Enable or disable MAC addresses updating
> (enabled by default)
> > +
> > +* --config(port,port)[,(port,port)]: Determines which ports are mapped
> to
> > + which ports for packet forwarding.
>
> Ditto
>
> >
> > To run the application in linux environment with 4 lcores, 16 ports
> > and 8 RX queues per lcore and MAC address updating enabled, issue the
> command:
> > @@ -108,6 +114,14 @@ updating enabled, issue the command:
> >
> > $ ./build/l2fwd -l 0-3 -n 4 -- -q 8 -p ffff
> >
> > +To run the application in linux environment with 4 lcores, 4 ports, 8
> > +RX queues per lcore and MAC address updating enabled, to forward RX
> > +traffic of ports 0 & 1 on ports 2 & 3 respectively and vice versa, issue
> > the
> command:
> > +
> > +.. code-block:: console
> > +
> > + $ ./build/l2fwd -l 0-3 -n 4 -- -q 8 -p f --config="(0,2)(1,3)"
> > +
> > Refer to the *DPDK Getting Started Guide* for general information on
> > running applications and the Environment Abstraction Layer (EAL) options.
> >
> > diff --git a/examples/l2fwd/main.c b/examples/l2fwd/main.c index
> > 09257aa..a8b98b9 100644
> > --- a/examples/l2fwd/main.c
> > +++ b/examples/l2fwd/main.c
> > @@ -38,6 +38,7 @@
> > #include <rte_ethdev.h>
> > #include <rte_mempool.h>
> > #include <rte_mbuf.h>
> > +#include <rte_string_fns.h>
> >
> > static volatile bool force_quit;
> >
> > @@ -67,6 +68,15 @@ static uint32_t l2fwd_enabled_port_mask = 0;
> > /* list of enabled ports */
> > static uint32_t l2fwd_dst_ports[RTE_MAX_ETHPORTS];
> >
> > +struct port_pair_params {
> > +#define NUM_PORTS 2
> > + uint16_t port[NUM_PORTS];
> > +} __rte_cache_aligned;
> > +
> > +static struct port_pair_params
> > +port_pair_params_array[RTE_MAX_ETHPORTS];
> > +static struct port_pair_params *port_pair_params; static uint16_t
> > +nb_port_pair_params = 1;
>
> Why this initialization to 1? Below (during parsing) it is initialized to 0,
> so I
> would leave this default initialized.
>
> > +
> > static unsigned int l2fwd_rx_queue_per_lcore = 1;
> >
> > #define MAX_RX_QUEUE_PER_LCORE 16
> > @@ -319,6 +329,60 @@ l2fwd_parse_portmask(const char *portmask)
> > return pm;
> > }
> >
> > +static int
> > +l2fwd_parse_port_pair_config(const char *q_arg) {
> > + enum fieldnames {
> > + FLD_PORT1 = 0,
> > + FLD_PORT2,
> > + _NUM_FLD
> > + };
> > + unsigned long int_fld[_NUM_FLD];
> > + const char *p, *p0 = q_arg;
> > + char *str_fld[_NUM_FLD];
> > + unsigned int size;
> > + char s[256];
> > + char *end;
> > + int i;
> > +
> > + nb_port_pair_params = 0;
> > +
> > + while ((p = strchr(p0, '(')) != NULL) {
> > + ++p;
> > + p0 = strchr(p, ')');
> > + if (p0 == NULL)
> > + return -1;
> > +
> > + size = p0 - p;
> > + if (size >= sizeof(s))
> > + return -1;
> > +
> > + snprintf(s, sizeof(s), "%.*s", size, p);
>
> Same comment as for recent l2fwd-event - this can be simple memcpy.
>
> > + if (rte_strsplit(s, sizeof(s), str_fld,
> > + _NUM_FLD, ',') != _NUM_FLD)
> > + return -1;
> > + for (i = 0; i < _NUM_FLD; i++) {
> > + errno = 0;
> > + int_fld[i] = strtoul(str_fld[i], &end, 0);
> > + if (errno != 0 || end == str_fld[i] ||
> > + int_fld[i] > RTE_MAX_ETHPORTS)
>
> I think this check should be >=, RTE_MAX_ETHPORTS is an invalid port id.
>
> > + return -1;
> > + }
> > + if (nb_port_pair_params >= RTE_MAX_ETHPORTS/2) {
> > + printf("exceeded max number of port pair params:
> %hu\n",
> > + nb_port_pair_params);
> > + return -1;
> > + }
> > + port_pair_params_array[nb_port_pair_params].port[0] =
> > + (uint16_t)int_fld[FLD_PORT1];
> > + port_pair_params_array[nb_port_pair_params].port[1] =
> > + (uint16_t)int_fld[FLD_PORT2];
> > + ++nb_port_pair_params;
> > + }
> > + port_pair_params = port_pair_params_array;
> > + return 0;
> > +}
>
> [...]
>
> > @@ -565,26 +686,40 @@ main(int argc, char **argv)
> > l2fwd_dst_ports[portid] = 0;
> > last_port = 0;
> >
> > - /*
> > - * Each logical core is assigned a dedicated TX queue on each port.
> > - */
> > - RTE_ETH_FOREACH_DEV(portid) {
> > - /* skip ports that are not enabled */
> > - if ((l2fwd_enabled_port_mask & (1 << portid)) == 0)
> > - continue;
> > + /* populate destination port details */
> > + if (port_pair_params != NULL) {
> > + uint16_t idx;
> > +
> > + for (idx = 0; idx < (nb_port_pair_params << 1); idx++) {
> > + if (idx % 2 == 0) {
> > + portid = port_pair_params[idx >> 1].port[0];
> > + l2fwd_dst_ports[portid] =
> > + port_pair_params[idx >> 1].port[1];
> > + } else {
> > + portid = port_pair_params[idx >> 1].port[1];
> > + l2fwd_dst_ports[portid] =
> > + port_pair_params[idx >> 1].port[0];
> > + }
>
> I think this conditional can be rephrased like:
>
> uint16_t idx, p;
> ...
> p = idx & 1;
> port_id = port_pair_params[idx >> 1].port[p];
> l2fwd_dst_ports[port_id] =
> port_pair_params[idx >> 1].port[p ^ 1];
>
> but I'm not sure which one is more readable - I leave you the decision, feel
> free to skip this comment altogether :).
>
> > + }
> > + } else {
> > + RTE_ETH_FOREACH_DEV(portid) {
> > + /* skip ports that are not enabled */
> > + if ((l2fwd_enabled_port_mask & (1 << portid)) == 0)
> > + continue;
> > +
> > + if (nb_ports_in_mask % 2) {
> > + l2fwd_dst_ports[portid] = last_port;
> > + l2fwd_dst_ports[last_port] = portid;
> > + } else {
> > + last_port = portid;
> > + }
> >
> > + nb_ports_in_mask++;
> > + }
> > if (nb_ports_in_mask % 2) {
> > - l2fwd_dst_ports[portid] = last_port;
> > - l2fwd_dst_ports[last_port] = portid;
> > + printf("Notice: odd number of ports in
> portmask.\n");
> > + l2fwd_dst_ports[last_port] = last_port;
> > }
> > - else
> > - last_port = portid;
> > -
> > - nb_ports_in_mask++;
> > - }
> > - if (nb_ports_in_mask % 2) {
> > - printf("Notice: odd number of ports in portmask.\n");
> > - l2fwd_dst_ports[last_port] = last_port;
> > }
> >
> > rx_lcore_id = 0;
> > @@ -613,7 +748,8 @@ main(int argc, char **argv)
> >
> > qconf->rx_port_list[qconf->n_rx_port] = portid;
> > qconf->n_rx_port++;
> > - printf("Lcore %u: RX port %u\n", rx_lcore_id, portid);
> > + printf("Lcore %u: RX port %u TX port %u\n", rx_lcore_id,
> > + portid, l2fwd_dst_ports[portid]);
> > }
> >
> > nb_mbufs = RTE_MAX(nb_ports * (nb_rxd + nb_txd +
> MAX_PKT_BURST +
> >
>
> Apart from these comments:
>
> Reviewed-by: Andrzej Ostruszka <aostrus...@marvell.com>
>
> With regards
> Andrzej Ostruszka
Thanks Andrzej,
Acked all the comments in V2.
