mod_sonic: translate DROPMON discard events to sonic ifIndex number-s…

…pace
sflow · Jun 11, 2024 · 5691800 · 5691800
1 parent 8b7bfca
commit 5691800
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Showing 3 changed files with 72 additions and 2 deletions.
diff --git a/src/Linux/hsflowd.h b/src/Linux/hsflowd.h
@@ -417,6 +417,7 @@ extern "C" {
 #define HSPEVENT_INTF_COUNTER_SAMPLE "icsample"  // (csample *) building intf counter-sample
 #define HSPEVENT_VM_COUNTER_SAMPLE "vcsample"    // (csample *) building vm counter-sample
 #define HSPEVENT_FLOW_SAMPLE "flow_sample"       // (HSPPendingSample *) building flow-sample
+#define HSPEVENT_INTF_EVENT_SAMPLE "evsample"    // (discard *) building event-sample
 #define HSPEVENT_FLOW_SAMPLE_RELEASED "flow_sample_released"  // (HSPPendingSample *) flow-sample after lookups completed
 #define HSPEVENT_XDR_SAMPLE "xdr_sample"         // fully-encoded SFDBuf
 #define HSPEVENT_CONFIG_START "config_start"     // begin config lines
@@ -491,6 +492,12 @@ extern "C" {
     bool suppress:1;
   } HSPPendingCSample;
 
+  typedef struct _HSPPendingEvtSample {
+    SFLEvent_discarded_packet *discard;
+    SFLNotifier *notifier;
+    bool suppress:1;
+  } HSPPendingEvtSample;
+
   typedef enum {
     HSP_TELEMETRY_FLOW_SAMPLES=0,
     HSP_TELEMETRY_COUNTER_SAMPLES,

diff --git a/src/Linux/mod_dropmon.c b/src/Linux/mod_dropmon.c
@@ -137,6 +137,7 @@ extern "C" {
     uint32_t ignoredDrops_rn;
     uint32_t totalDrops_thisTick; // for threshold
     bool dropmon_disabled;
+    EVEvent *evt_intf_es;
   } HSP_mod_DROPMON;
 
 
@@ -942,8 +943,16 @@ That would allow everything to stay on the stack as it does here, which has nice
       SFLADD_ELEMENT(&discard, &rnElem);
     }
 
-    sfl_notifier_writeEventSample(notifier, &discard);
-    sp->telemetry[HSP_TELEMETRY_EVENT_SAMPLES]++;
+    HSPPendingEvtSample es = { .notifier = notifier, .discard = &discard };
+    if(mdata->evt_intf_es)
+      EVEventTx(mod, mdata->evt_intf_es, &es, sizeof(es));
+    if(es.suppress) {
+      sp->telemetry[HSP_TELEMETRY_EVENT_SAMPLES_SUPPRESSED]++;
+    }
+    else {
+      sfl_notifier_writeEventSample(notifier, &discard);
+      sp->telemetry[HSP_TELEMETRY_EVENT_SAMPLES]++;
+    }
 
     // first successful event confirms we are up and running
     if(mdata->state == HSP_DROPMON_STATE_START)
@@ -1234,6 +1243,7 @@ That would allow everything to stay on the stack as it does here, which has nice
     EVEventRx(mod, EVGetEvent(mdata->packetBus, EVEVENT_TICK), evt_tick);
     EVEventRx(mod, EVGetEvent(mdata->packetBus, EVEVENT_DECI), evt_deci);
     EVEventRx(mod, EVGetEvent(mdata->packetBus, EVEVENT_FINAL), evt_final);
+    mdata->evt_intf_es = EVGetEvent(mdata->packetBus, HSPEVENT_INTF_EVENT_SAMPLE);
   }
 
 #if defined(__cplusplus)

diff --git a/src/Linux/mod_sonic.c b/src/Linux/mod_sonic.c
@@ -2322,6 +2322,58 @@ extern "C" {
     }
   }
 
+  /*_________________---------------------------__________________
+    _________________       evt_flow_sample     __________________
+    -----------------___________________________------------------
+   packet bus
+  */
+
+  static void evt_discard_sample(EVMod *mod, EVEvent *evt, void *data, size_t dataLen) {
+    HSP *sp = (HSP *)EVROOTDATA(mod);
+    HSPPendingEvtSample *ps = (HSPPendingEvtSample *)data;
+    // find and translate all ifIndex fields from the OS (Linux) ifIndex namespace to
+    // the SONiC ifIndex namespace.
+    HSPSonicPort *prt = NULL;
+    uint32_t dsClass = ps->discard->ds_class;
+    uint32_t osIndex = ps->discard->ds_index;
+    if(ps->discard->ds_class == SFL_DSCLASS_IFINDEX)
+      prt = getPortByOsIndex(mod, osIndex);
+    if(prt == NULL
+       || prt->ifIndex == HSP_SONIC_IFINDEX_UNDEFINED) {
+      // for troubleshooting we can allow this through (untranslated) with:
+      // "sonic{suppressOther=off}"
+      if(!sp->sonic.suppressOther)
+	return;
+      // Unfortunately we might suppress useful discard events that were associated with,
+      // say, VLAN interfaces or the docker bridge here.  So rather than suppress them
+      // altogether, translate them as coming from dataSource 0:0x3FFFFFFF, meaning "internal"
+      EVDebug(mod, 2, "discard sample from non-sonic port (class=%u, osIndex=%u)", dsClass, osIndex);
+      // ps->suppress = YES;
+    }
+
+    uint32_t dsIndexAlias = prt ? prt->ifIndex : SFL_INTERNAL_INTERFACE;
+    // fix datasource
+    sfl_notifier_set_dsAlias(ps->notifier, dsIndexAlias);
+    // fix in/out
+    if(ps->discard->input
+       && ps->discard->input != SFL_INTERNAL_INTERFACE) {
+      // translate, or mark unknown
+      HSPSonicPort *in = getPortByOsIndex(mod, ps->discard->input);
+      ps->discard->input = (in && in->ifIndex != HSP_SONIC_IFINDEX_UNDEFINED)
+	? in->ifIndex
+	: 0;
+    }
+    if(ps->discard->output
+       && ps->discard->output != SFL_INTERNAL_INTERFACE
+       && (ps->discard->output & 0x80000000) == 0) {
+      // translate, or mark unknown
+      HSPSonicPort *out = getPortByOsIndex(mod, ps->discard->output);
+      ps->discard->output = (out && out->ifIndex != HSP_SONIC_IFINDEX_UNDEFINED)
+	? out->ifIndex
+	: 0;
+    }
+  }
+
   /*_________________---------------------------__________________
     _________________       evt_cntr_sample     __________________
     -----------------___________________________------------------
@@ -2454,6 +2506,7 @@ extern "C" {
 
     // intercept samples before they go out so we can rewrite ifindex numbers
     EVEventRx(mod, EVGetEvent(mdata->packetBus, HSPEVENT_FLOW_SAMPLE), evt_flow_sample);
+    EVEventRx(mod, EVGetEvent(mdata->packetBus, HSPEVENT_INTF_EVENT_SAMPLE), evt_discard_sample);
     EVEventRx(mod, EVGetEvent(mdata->pollBus, HSPEVENT_INTF_COUNTER_SAMPLE), evt_cntr_sample);
   }