app/testpmd: reduce memory consumption

app/testpmd: reduce memory consumption

Following [1], testpmd memory consumption has skyrocketted.
The rte_port structure has gotten quite fat.

struct rte_port {
[...]
  struct rte_eth_rxconf rx_conf[65536];            /* 266280 3145728 */
  /* --- cacheline 53312 boundary (3411968 bytes) was 40 bytes ago --- */
  struct rte_eth_txconf tx_conf[65536];            /* 3412008 3670016 */
  /* --- cacheline 110656 boundary (7081984 bytes) was 40 bytes ago --- */
[...]
  /* size: 8654936, cachelines: 135234, members: 31 */
[...]

testpmd handles RTE_MAX_ETHPORTS ports (32 by default) which means that it
needs ~256MB just for this internal representation.

The reason is that a testpmd rte_port (the name is quite confusing, as
it is a local type) maintains configurations for all queues of a port.
But where you would expect testpmd to use RTE_MAX_QUEUES_PER_PORT as the
maximum queue count, the rte_port uses MAX_QUEUE_ID set to 64k.

Prefer the ethdev maximum value.

After this patch:
struct rte_port {
[...]
  struct rte_eth_rxconf      rx_conf[1025];        /*  8240 49200 */
  /* --- cacheline 897 boundary (57408 bytes) was 32 bytes ago --- */
  struct rte_eth_txconf      tx_conf[1025];        /* 57440 57400 */
  /* --- cacheline 1794 boundary (114816 bytes) was 24 bytes ago --- */
[...]
  /* size: 139488, cachelines: 2180, members: 31 */
[...]

With this, we can ask for less memory in test-null.sh.

[1]: https://git.dpdk.org/dpdk/commit/?id=436b3a6b6e62

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>