events: Rework events

Flatten event model to more closely match the metric reporting format.
Don't nest events under IDs, IDs are now top-level.

Bug: 110497903
Test: using event command on red board
Change-Id: If25aeefa3c295d7c1e6032ef4ea8e20f7396e949
Signed-off-by: Garret Kelly <gdk@google.com>

2 files changed, 32 insertions, 22 deletions

diff --git a/citadel/updater/updater.cpp b/citadel/updater/updater.cpp
index ec8fb3f..ed58895 100644
--- a/citadel/updater/updater.cpp
+++ b/citadel/updater/updater.cpp
@@ -1018,8 +1018,8 @@ static uint32_t do_event(AppClient &app, int argc, char *argv[])
     uint64_t usecs = evt.uptime_usecs - (secs * 1000000UL);
     printf("event record %" PRIu64 "/%" PRIu64 ".%06" PRIu64 ": ",
            evt.reset_count, secs, usecs);
-    printf("%d  0x%08x 0x%08x 0x%08x\n", evt.id,
-           evt.u.raw.w[0], evt.u.raw.w[1], evt.u.raw.w[2]);
+    printf("%d  %d  0x%08x 0x%08x 0x%08x\n", evt.id, evt.priority,
+           evt.event.raw.w[0], evt.event.raw.w[1], evt.event.raw.w[2]);
   }
 
   return rv;
diff --git a/nugget/include/citadel_events.h b/nugget/include/citadel_events.h
index 336f3c5..c25af55 100644
--- a/nugget/include/citadel_events.h
+++ b/nugget/include/citadel_events.h
@@ -44,47 +44,57 @@ extern "C" {
  * instead of changing things.
  */
 
+/*
+ * Event priority.  Stored events of lower priority will be evicted to store
+ * higher-priority events if the queue is full.
+ */
+enum event_priority {
+  EVENT_PRIORITY_LOW = 0,
+  EVENT_PRIORITY_MEDIUM = 1,
+  EVENT_PRIORITY_HIGH = 2,
+};
+
+/*
+ * Event ID values live forever.
+ * Add to the list, but NEVER change or delete existing entries.
+ */
+enum event_id {
+  EVENT_NONE = 0,      // Unused ID, used as empty marker.
+  EVENT_ALERT = 1,     // Globalsec alert fired.
+  EVENT_REBOOTED = 2,  // Device rebooted.
+};
+
 /* Please do not change the size of this struct */
 #define EVENT_RECORD_SIZE 64
 struct event_record {
   uint64_t reset_count;                 /* zeroed by Citadel power cycle */
   uint64_t uptime_usecs;                /* since last Citadel reset */
   uint32_t id;
+  uint32_t priority;
   union {
     /* id-specific information goes here */
     struct {
       uint32_t intr_sts[3];
     } alert;
     struct {
-      uint32_t bad_thing;
-    } citadel;
-    struct {
-      uint32_t okay_thing;
-    } info;
+      uint32_t rstsrc;
+      uint32_t exitpd;
+      uint32_t which0;
+      uint32_t which1;
+    } rebooted;
 
     /* uninterpreted */
     union {
-      uint32_t w[11];
-      uint16_t h[22];
-      uint8_t  b[44];
+      uint32_t w[10];
+      uint16_t h[20];
+      uint8_t b[40];
     } raw;
-  } u;
+  } event;
 } __packed;
 /* Please do not change the size of this struct */
 static_assert(sizeof(struct event_record) == EVENT_RECORD_SIZE,
               "Muting the Immutable");
 
-/*
- * Event ID values live forever.
- * Add to the list, but NEVER change or delete existing entries.
-*/
-enum event_id {
-  EVENT_NONE = 0,                       /* No valid event exists with this ID */
-  EVENT_ALERT = 1,                      /* Security alert reported */
-  EVENT_CITADEL = 2,                    /* Bad: panic, stack overflow, etc. */
-  EVENT_INFO = 3,                       /* FYI: normal reboot, etc. */
-};
-
 #ifdef __cplusplus
 }
 #endif