From 815611b3675bca733aa7e70b0c99a09ad0555aef Mon Sep 17 00:00:00 2001 From: Conor Walsh Date: Tue, 6 Jul 2021 11:57:55 +0000 Subject: [PATCH] examples/l3fwd: remove useless reloads in EM main loop This patch aligns the l3fwd EM code with the changes made to LPM in commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM main loop"). This change ensures the compiler knows that the lcore config variables are constant values and the compiler will then optimize the code accordingly. Signed-off-by: Conor Walsh Reviewed-by: Ruifeng Wang Reviewed-by: David Marchand --- examples/l3fwd/l3fwd_em.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/examples/l3fwd/l3fwd_em.c b/examples/l3fwd/l3fwd_em.c index 01f8dff485..43fc7612e7 100644 --- a/examples/l3fwd/l3fwd_em.c +++ b/examples/l3fwd/l3fwd_em.c @@ -632,14 +632,16 @@ em_main_loop(__rte_unused void *dummy) lcore_id = rte_lcore_id(); qconf = &lcore_conf[lcore_id]; - if (qconf->n_rx_queue == 0) { + const uint16_t n_rx_q = qconf->n_rx_queue; + const uint16_t n_tx_p = qconf->n_tx_port; + if (n_rx_q == 0) { RTE_LOG(INFO, L3FWD, "lcore %u has nothing to do\n", lcore_id); return 0; } RTE_LOG(INFO, L3FWD, "entering main loop on lcore %u\n", lcore_id); - for (i = 0; i < qconf->n_rx_queue; i++) { + for (i = 0; i < n_rx_q; i++) { portid = qconf->rx_queue_list[i].port_id; queueid = qconf->rx_queue_list[i].queue_id; @@ -659,7 +661,7 @@ em_main_loop(__rte_unused void *dummy) diff_tsc = cur_tsc - prev_tsc; if (unlikely(diff_tsc > drain_tsc)) { - for (i = 0; i < qconf->n_tx_port; ++i) { + for (i = 0; i < n_tx_p; ++i) { portid = qconf->tx_port_id[i]; if (qconf->tx_mbufs[portid].len == 0) continue; @@ -675,7 +677,7 @@ em_main_loop(__rte_unused void *dummy) /* * Read packet from RX queues */ - for (i = 0; i < qconf->n_rx_queue; ++i) { + for (i = 0; i < n_rx_q; ++i) { portid = qconf->rx_queue_list[i].port_id; queueid = qconf->rx_queue_list[i].queue_id; nb_rx = rte_eth_rx_burst(portid, queueid, pkts_burst, -- 2.20.1