[dpdk-dev] [PATCH 1/4] rte_sched: make RED optional at runtime

[Stephen Hemminger]

We want to be able to build with RTE_SCHED_RED enabled but
allow disabling RED on a per-queue basis at runtime. This is
handled by allowing RED min/max to be zero to indicate that
RED is not being used.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>

--- a/lib/librte_sched/rte_sched.c      2014-12-08 09:28:20.782545529 -0800
+++ b/lib/librte_sched/rte_sched.c      2014-12-08 09:28:20.782545529 -0800
@@ -636,6 +636,12 @@ rte_sched_port_config(struct rte_sched_p
                uint32_t j;

                for (j = 0; j < e_RTE_METER_COLORS; j++) {
+                       /* if min/max are both zero, then RED is disabled */
+                       if ((params->red_params[i][j].min_th |
+                            params->red_params[i][j].max_th) == 0) {
+                               continue;
+                       }
+
                        if (rte_red_config_init(&port->red_config[i][j],
                                params->red_params[i][j].wq_log2,
                                params->red_params[i][j].min_th,
@@ -1069,6 +1075,9 @@ rte_sched_port_red_drop(struct rte_sched
        color = rte_sched_port_pkt_read_color(pkt);
        red_cfg = &port->red_config[tc_index][color];

+       if ( (red_cfg->min_th | red_cfg->max_th) == 0)
+               return 0;
+
        qe = port->queue_extra + qindex;
        red = &qe->red;