Torus-2QoS needs 8 VLs, and complete control over sl2vl maps, in order
to provide 2 QoS levels with routing that is free of credit loops on torus
fabrics. Warn to this effect if an insufficient max_vls configuration
or a non-default qos_sl2vl configuration is detected.
Also, torus-2QoS needs to use VLs 0-3 to implement one QoS level, and
VLs 4-7 to implement the other. The VLarb weights for VLs 0-3 should
all have the same value, and similarly for the weights for VLs 4-7.
Otherwise, differences in data rates for different paths may cause
hard-to-diagnose application issues. Warn to this effect when
detected.
Signed-off-by: Jim Schutt <jasc...@sandia.gov>
---
opensm/opensm/osm_torus.c | 87 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 87 insertions(+), 0 deletions(-)
diff --git a/opensm/opensm/osm_torus.c b/opensm/opensm/osm_torus.c
index aeb4fe6..784955d 100644
--- a/opensm/opensm/osm_torus.c
+++ b/opensm/opensm/osm_torus.c
@@ -9038,6 +9038,84 @@ out:
}
static
+void check_vlarb_config(const char *vlarb_str, bool is_default,
+ const char *str, const char *pri, osm_log_t *log)
+{
+ unsigned total_weight[IB_MAX_NUM_VLS] = {0,};
+ unsigned i = 0, v, vl = 0;
+ char *end;
+ bool uniform;
+
+ while (*vlarb_str && i++ < 2 * IB_NUM_VL_ARB_ELEMENTS_IN_BLOCK) {
+ v = strtoul(vlarb_str, &end, 0);
+ if (*end)
+ end++;
+ vlarb_str = end;
+ if (i & 0x1)
+ vl = v & 0xf;
+ else
+ total_weight[vl] += v & 0xff;
+ }
+ uniform = true;
+ v = total_weight[0];
+ for (i = 1; i < 8; i++) {
+ if (i == 4)
+ v = total_weight[i];
+ if (total_weight[i] != v)
+ uniform = false;
+ }
+ if (!uniform)
+ OSM_LOG(log, OSM_LOG_INFO,
+ "Warning: torus-2QoS requires same VLarb weights for "
+ "VLs 0-3; also for VLs 4-7: not true for %s "
+ "%s_vlarb_%s\n",
+ (is_default ? "default" : "configured"), str, pri);
+}
+
+static
+void check_qos_config(osm_qos_options_t *opt, bool tgt_is_default,
+ const char *str, osm_log_t *log)
+{
+ const char *vlarb_str;
+ bool is_default;
+
+ if (opt->max_vls > 0 && opt->max_vls < 8)
+ OSM_LOG(log, OSM_LOG_INFO,
+ "Warning: full torus-2QoS functionality not available "
+ "for configured %s_max_vls = %d\n", str, opt->max_vls);
+
+ if (opt->vlarb_high) {
+ is_default = false;
+ vlarb_str = opt->vlarb_high;
+ } else{
+ is_default = true;
+ vlarb_str = OSM_DEFAULT_QOS_VLARB_HIGH;
+ }
+ /*
+ * Only check values that were actually configured, or the overall
+ * defaults that target-specific (CA, switch port, etc) defaults
+ * are set from.
+ */
+ if (!is_default || tgt_is_default)
+ check_vlarb_config(vlarb_str, is_default, str, "high", log);
+
+ if (opt->vlarb_low) {
+ is_default = false;
+ vlarb_str = opt->vlarb_low;
+ } else {
+ is_default = true;
+ vlarb_str = OSM_DEFAULT_QOS_VLARB_LOW;
+ }
+ if (!is_default || tgt_is_default)
+ check_vlarb_config(vlarb_str, is_default, str, "low", log);
+
+ if (opt->sl2vl)
+ OSM_LOG(log, OSM_LOG_INFO,
+ "Warning: torus-2QoS must override configured "
+ "%s_sl2vl to generate deadlock-free routes\n", str);
+}
+
+static
int torus_build_lfts(void *context)
{
int status = -1;
@@ -9111,9 +9189,18 @@ out:
if (torus)
teardown_torus(torus);
} else {
+ osm_subn_opt_t *opt = &torus->osm->subn.opt;
+ osm_log_t *log = &torus->osm->log;
+
if (ctx->torus)
teardown_torus(ctx->torus);
ctx->torus = torus;
+
+ check_qos_config(&opt->qos_options, 1, "qos", log);
+ check_qos_config(&opt->qos_ca_options, 0, "qos_ca", log);
+ check_qos_config(&opt->qos_sw0_options, 0, "qos_sw0", log);
+ check_qos_config(&opt->qos_swe_options, 0, "qos_swe", log);
+ check_qos_config(&opt->qos_rtr_options, 0, "qos_rtr", log);
}
teardown_fabric(fabric);
return status;
--
1.6.2.2
--
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