Re: [dpdk-dev] [PATCH] examples/ip_pipeline: add link show to the cli

["Dumitrescu, Cristian" <cristian.dumitrescu@intel.com>]

> -----Original Message-----
> From: Laatz, Kevin
> Sent: Friday, June 8, 2018 5:31 PM
> To: dev@dpdk.org
> Cc: Dumitrescu, Cristian <cristian.dumitrescu@intel.com>; Singh, Jasvinder
> <jasvinder.singh@intel.com>; Laatz, Kevin <kevin.laatz@intel.com>
> Subject: [PATCH] examples/ip_pipeline: add link show to the cli
> 
> Add the functionality to track links in the application. This enables the
> user to print the name, mac address and per-port statistics for each link
> in the application.
> 
> Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
> ---
>  examples/ip_pipeline/cli.c  | 103
> ++++++++++++++++++++++++++++++++++++++++++++
>  examples/ip_pipeline/link.c |   6 +++
>  examples/ip_pipeline/link.h |   3 ++
>  3 files changed, 112 insertions(+)
> 
> diff --git a/examples/ip_pipeline/cli.c b/examples/ip_pipeline/cli.c
> index c9587f5..b7fba3b 100644
> --- a/examples/ip_pipeline/cli.c
> +++ b/examples/ip_pipeline/cli.c
> @@ -9,6 +9,7 @@
> 
>  #include <rte_common.h>
>  #include <rte_cycles.h>
> +#include <rte_ethdev.h>
> 
>  #include "cli.h"
>  #include "kni.h"
> @@ -4355,6 +4356,103 @@ cmd_thread_pipeline_disable(char **tokens,
>  	}
>  }
> 
> +/* Print the link stats and info */
> +static void
> +print_link_info(struct link *link, char *out, size_t out_size)
> +{
> +	struct rte_eth_stats stats;
> +	struct ether_addr mac_addr;
> +	struct rte_eth_link eth_link;
> +
> +	memset(&stats, 0, sizeof(stats));
> +	rte_eth_stats_get(link->port_id, &stats);
> +
> +	rte_eth_macaddr_get(link->port_id, &mac_addr);
> +	rte_eth_link_get(link->port_id, &eth_link);
> +
> +	snprintf(out, out_size,
> +		"\n"
> +		"Link name: %s\n"
> +		"\tPort %u MAC: %02"PRIx8":%02"PRIx8":%02"PRIx8
> +		":%02"PRIx8":%02"PRIx8":%02"PRIx8"\n"
> +		"\tLink Status: %s\n"
> +		"\tLink Speed: %u\n"
> +		"\n"
> +		"\tRX info:\n"
> +		"\t\tQueues: %u\n"
> +		"\t\tPackets: %" PRIu64
> +		"\t\tBytes: %" PRIu64"\n"
> +		"\t\tErrors: %" PRIu64
> +		"\t\tMissed: %" PRIu64
> +		"\t\tNo-mbuf: %" PRIu64"\n"
> +		"\tTX info:\n"
> +		"\t\tQueues: %u\n"
> +		"\t\tPackets: %" PRIu64
> +		"\t\tBytes: %" PRIu64"\n"
> +		"\t\tErrors: %" PRIu64"\n",
> +		link->name,
> +		link->port_id,
> +		mac_addr.addr_bytes[0], mac_addr.addr_bytes[1],
> +		mac_addr.addr_bytes[2], mac_addr.addr_bytes[3],
> +		mac_addr.addr_bytes[4], mac_addr.addr_bytes[5],
> +		eth_link.link_status == 1 ? "UP" : "DOWN",
> +		eth_link.link_speed,
> +		link->n_rxq,
> +		stats.ipackets,
> +		stats.ibytes,
> +		stats.ierrors,
> +		stats.imissed,
> +		stats.rx_nombuf,
> +		link->n_txq,
> +		stats.opackets,
> +		stats.obytes,
> +		stats.oerrors);
> +}

Can we organize this as table, so for each link we print exactly one line?

If one link does not fit into a single line, we can have a print_link_info_short() that is used when all links are printed, and a print_link_info_long() that is used only when a single link is printed.

Don't forget about a function to print the table header. :)

> +
> +/*
> + * link show [<link_name>]
> + */
> +static void
> +cmd_link_show(char **tokens, uint32_t n_tokens, char *out, size_t
> out_size)
> +{
> +	struct link *link;
> +	struct link_list *link_list;
> +	char *link_name;
> +	uint32_t i = 0;
> +
> +	if (n_tokens != 2 && n_tokens != 3) {
> +		snprintf(out, out_size, MSG_ARG_MISMATCH, tokens[0]);
> +		return;
> +	}
> +
> +	link_list = links_get();

We don't need this function, the lined list of links is a global public object, please access it directly.

> +
> +	if (TAILQ_EMPTY(link_list)) {
> +		snprintf(out, out_size, "No links - nothing to show\n");
> +		return;
> +	}

No need for this, could be detected by empty table (only table header gets printed).

> +
> +	if (n_tokens == 2) {
> +		TAILQ_FOREACH(link, link_list, node) {
> +			size_t os = out_size - (i * strlen(out));
> +			char *o = &out[i * strlen(out)];
> +
> +			if (os == 0) {
> +				snprintf(out, out_size, MSG_CMD_FAIL,
> +						"Output buffer too small");
> +				return;
> +			}
> +

This check can be removed, no need to worry about output buffer overrun.

> +			print_link_info(link, o, os);
> +			i++;
> +		}
> +	} else {
> +		link_name = tokens[2];
> +		link = link_find(link_name);

What if link with this name does not exist? Checking that link is not NULL might avoid a crash as well :)

> +		print_link_info(link, out, out_size);
> +	}
> +}
> +
>  void
>  cli_process(char *in, char *out, size_t out_size)
>  {
> @@ -4380,6 +4478,11 @@ cli_process(char *in, char *out, size_t out_size)
>  	}
> 
>  	if (strcmp(tokens[0], "link") == 0) {
> +		if (strcmp(tokens[1], "show") == 0) {
> +			cmd_link_show(tokens, n_tokens, out, out_size);
> +			return;
> +		}
> +
>  		cmd_link(tokens, n_tokens, out, out_size);
>  		return;
>  	}
> diff --git a/examples/ip_pipeline/link.c b/examples/ip_pipeline/link.c
> index b8a431f..b11f0c1 100644
> --- a/examples/ip_pipeline/link.c
> +++ b/examples/ip_pipeline/link.c
> @@ -36,6 +36,12 @@ link_find(const char *name)
>  	return NULL;
>  }
> 
> +struct link_list *
> +links_get(void)
> +{
> +	return &link_list;
> +}
> +

Function to be removed, used linked list of links directly (see comment above).

>  static struct rte_eth_conf port_conf_default = {
>  	.link_speeds = 0,
>  	.rxmode = {
> diff --git a/examples/ip_pipeline/link.h b/examples/ip_pipeline/link.h
> index 37d3dc4..10f9d51 100644
> --- a/examples/ip_pipeline/link.h
> +++ b/examples/ip_pipeline/link.h
> @@ -30,6 +30,9 @@ link_init(void);
>  struct link *
>  link_find(const char *name);
> 
> +struct link_list *
> +links_get(void);
> +
>  struct link_params_rss {
>  	uint32_t queue_id[LINK_RXQ_RSS_MAX];
>  	uint32_t n_queues;
> --
> 2.9.5