Re: [dpdk-dev] [PATCH 2/5] app/proc-info: add to use apistats

["Varghese, Vipin" <vipin.varghese@intel.com>]

snipped
>  		"  --xstats-ids IDLIST: to display xstat values by id. "
>  			"The argument is comma-separated list of xstat ids to
> print out.\n"
> +		"  --apistats: to display api statistics, disabled by default\n"
As per the code base the logic ` rte_apicounts->rx_burst_counts[lcore_id]++; and rte_apicounts->tx_burst_counts[lcore_id]++;`. This expect `apistats_init` isn primary before `proc-info`. So I have 2 quereies

1. with this logic does all dpdk-examples will be updated to invoke `apistats_init`?
2. what is mechanism in place to inform all dpdk user that `just like rte_eal_init one has to explicitly invoke apistats_init too`?

since I am not clear with the code flow, please feel free to explain the logic or expectation.

snipped
> 
> +static void
> +display_apistats(void)
> +{
> +	static const char *api_stats_border = "########################";
> +	uint16_t i;
> +	struct rte_apistats t0_count, t1_count;
> +	memcpy(&t0_count, rte_apicounts, sizeof(struct rte_apistats));
Any specific reason not to use `rte_memcpy` and invoke system library call `memcpy`

> +	sleep(1);
> +	memcpy(&t1_count, rte_apicounts, sizeof(struct rte_apistats));
> +	for (i = 0; i < RTE_MAX_LCORE; i++) {
I am against the idea of iterating RTE_MAX_LCORE, as for any valid DPDK primary application the actual core count may vary between `1 to RTE_MAX_LCORE`

> +		if (t1_count.lcoreid_list[i] != 0) {
> +			uint64_t rx_count_delta = t1_count.rx_burst_counts[i]
> +				- t0_count.rx_burst_counts[i];
> +			uint64_t tx_count_delta = t1_count.tx_burst_counts[i]
> +				- t0_count.tx_burst_counts[i];
> +			printf("\n  %s api statistics for lcoreid: %d %s\n",
> +				api_stats_border, i, api_stats_border);
Suggestion: Since most of DPDK application uses dedicated core to RX and TX, would not it easier only display the lcores which does the operation. That is skip lcores where `count_delta` are 0?

> +			printf("  rx_burst_count: %13"PRIu64""
> +				" rx_burst_count_delta: %13"PRIu64"\n",
> +				t1_count.rx_burst_counts[i],
> +				rx_count_delta);
> +			printf("  tx_burst_count: %13"PRIu64""
> +				" tx_burst_count_delta: %13"PRIu64"\n",
> +				t1_count.tx_burst_counts[i],
> +				tx_count_delta);
> +			printf("  tx/rx_rate: %3.2f\n",
> +				(rx_count_delta) ? (double)tx_count_delta
> +				/ rx_count_delta : 0.0);

snipped

>  	if (enable_iter_mempool)
>  		iter_mempool(mempool_iter_name);
> +	if (enable_apistats)
> +		display_apistats();
> 
>  	RTE_ETH_FOREACH_DEV(i)
>  		rte_eth_dev_close(i);
> --
> 2.18.0