[dpdk-dev] [PATCH] app/testpmd: fix RSS-hash-key size

[Ananyev, Konstantin]

Hi Awal,

As I said in the offline discussion, here are few nits
that I think need to be addressed.
See below. 
Konstantin

> 
> RSS hash-key-size is retrieved from device configuration instead of using a fixed size of 40 bytes.
> 
> Fixes: f79959ea1504 ("app/testpmd: allow to configure RSS hash key")
> 
> Signed-off-by: Mohammad Abdul Awal <mohammad.abdul.awal at intel.com>
> ---
>  app/test-pmd/cmdline.c | 24 +++++++++++++++++-------  app/test-pmd/config.c  | 17 ++++++++++++++---
>  2 files changed, 31 insertions(+), 10 deletions(-)
> 
> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index f90befc..14412b4 100644
> --- a/app/test-pmd/cmdline.c
> +++ b/app/test-pmd/cmdline.c
> @@ -1608,7 +1608,6 @@ struct cmd_config_rss_hash_key {
>  	cmdline_fixed_string_t key;
>  };
> 
> -#define RSS_HASH_KEY_LENGTH 40
>  static uint8_t
>  hexa_digit_to_value(char hexa_digit)
>  {
> @@ -1640,20 +1639,30 @@ cmd_config_rss_hash_key_parsed(void *parsed_result,
>  			       __attribute__((unused)) void *data)  {
>  	struct cmd_config_rss_hash_key *res = parsed_result;
> -	uint8_t hash_key[RSS_HASH_KEY_LENGTH];
> +	uint8_t hash_key[16 * 4];

No need for hard-coded constants.
I'd suggest to keep RSS_HASH_KEY_LENGTH, just increase it to 52 (or might be even bigger) value.

>  	uint8_t xdgt0;
>  	uint8_t xdgt1;
>  	int i;
> +	struct rte_eth_dev_info dev_info;
> +	uint8_t hash_key_size;
> 
> +	memset(&dev_info, 0, sizeof(dev_info));
> +	rte_eth_dev_info_get(res->port_id, &dev_info);
> +	if (dev_info.hash_key_size > 0) {

&& dev_info.hash_key_size <= sizeof(hash_key) {

> +		hash_key_size = dev_info.hash_key_size;
> +	} else {
> +		printf("dev_info did not provide a valid hash key size\n");
> +		return;
> +	}
>  	/* Check the length of the RSS hash key */
> -	if (strlen(res->key) != (RSS_HASH_KEY_LENGTH * 2)) {
> +	if (strlen(res->key) != (hash_key_size * 2)) {
>  		printf("key length: %d invalid - key must be a string of %d"
>  		       "hexa-decimal numbers\n", (int) strlen(res->key),
> -		       RSS_HASH_KEY_LENGTH * 2);
> +			   hash_key_size * 2);
>  		return;
>  	}
>  	/* Translate RSS hash key into binary representation */
> -	for (i = 0; i < RSS_HASH_KEY_LENGTH; i++) {
> +	for (i = 0; i < hash_key_size; i++) {
>  		xdgt0 = parse_and_check_key_hexa_digit(res->key, (i * 2));
>  		if (xdgt0 == 0xFF)
>  			return;
> @@ -1663,7 +1672,7 @@ cmd_config_rss_hash_key_parsed(void *parsed_result,
>  		hash_key[i] = (uint8_t) ((xdgt0 * 16) + xdgt1);
>  	}
>  	port_rss_hash_key_update(res->port_id, res->rss_type, hash_key,
> -				 RSS_HASH_KEY_LENGTH);
> +			hash_key_size);
>  }
> 
>  cmdline_parse_token_string_t cmd_config_rss_hash_key_port = @@ -1692,7 +1701,8 @@ cmdline_parse_inst_t
> cmd_config_rss_hash_key = {
>  		"port config X rss-hash-key ipv4|ipv4-frag|ipv4-tcp|ipv4-udp|"
>  		"ipv4-sctp|ipv4-other|ipv6|ipv6-frag|ipv6-tcp|ipv6-udp|"
>  		"ipv6-sctp|ipv6-other|l2-payload|"
> -		"ipv6-ex|ipv6-tcp-ex|ipv6-udp-ex 80 hexa digits\n",
> +		"ipv6-ex|ipv6-tcp-ex|ipv6-udp-ex "
> +		"80 hexa digits (104 hexa digits for fortville)\n",

No need to mention particular NIC (Fortville) here.
I'd say better: 'array of hex digits (variable size, NIC dependent)' or so.

>  	.tokens = {
>  		(void *)&cmd_config_rss_hash_key_port,
>  		(void *)&cmd_config_rss_hash_key_config,
> diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c index bfcbff9..851408b 100644
> --- a/app/test-pmd/config.c
> +++ b/app/test-pmd/config.c
> @@ -1012,14 +1012,25 @@ void
>  port_rss_hash_conf_show(portid_t port_id, char rss_info[], int show_rss_key)  {
>  	struct rte_eth_rss_conf rss_conf;
> -	uint8_t rss_key[10 * 4] = "";
> +	uint8_t rss_key[16 * 4] = "";

better rss_key[RSS_HASH_KEY_LENGTH ], and I think there is no need to put '0' into first element.

>  	uint64_t rss_hf;
>  	uint8_t i;
>  	int diag;
> +	struct rte_eth_dev_info dev_info;
> +	uint8_t hash_key_size;
> 
>  	if (port_id_is_invalid(port_id, ENABLED_WARN))
>  		return;
> 
> +	memset(&dev_info, 0, sizeof(dev_info));
> +	rte_eth_dev_info_get(port_id, &dev_info);
> +	if (dev_info.hash_key_size > 0) {
> +		hash_key_size = dev_info.hash_key_size;
> +	} else {
> +		printf("dev_info did not provide a valid hash key size\n");
> +		return;
> +	}
> +
>  	rss_conf.rss_hf = 0;
>  	for (i = 0; i < RTE_DIM(rss_type_table); i++) {
>  		if (!strcmp(rss_info, rss_type_table[i].str)) @@ -1028,7 +1039,7 @@ port_rss_hash_conf_show(portid_t port_id, char
> rss_info[], int show_rss_key)
> 
>  	/* Get RSS hash key if asked to display it */
>  	rss_conf.rss_key = (show_rss_key) ? rss_key : NULL;
> -	rss_conf.rss_key_len = sizeof(rss_key);
> +	rss_conf.rss_key_len = hash_key_size;
>  	diag = rte_eth_dev_rss_hash_conf_get(port_id, &rss_conf);
>  	if (diag != 0) {
>  		switch (diag) {
> @@ -1058,7 +1069,7 @@ port_rss_hash_conf_show(portid_t port_id, char rss_info[], int show_rss_key)
>  	if (!show_rss_key)
>  		return;
>  	printf("RSS key:\n");
> -	for (i = 0; i < sizeof(rss_key); i++)
> +	for (i = 0; i < hash_key_size; i++)
>  		printf("%02X", rss_key[i]);
>  	printf("\n");
>  }
> --
> 2.7.4