From ddd89ba12d03d648e9bb820c6a4f48b1f96f15d2 Mon Sep 17 00:00:00 2001
From: Maria Matejka <mq@ucw.cz>
Date: Mon, 10 Feb 2020 15:01:36 +0100
Subject: [PATCH] BGP: Moved the suppressed and stale flags to pflags

---
 nest/route.h        |  6 -----
 proto/bgp/attrs.c   | 53 +++++++++++++++++++++++++--------------------
 proto/bgp/bgp.h     |  4 ++++
 proto/bgp/packets.c |  2 --
 proto/pipe/pipe.c   |  6 ++++-
 5 files changed, 39 insertions(+), 32 deletions(-)

diff --git a/nest/route.h b/nest/route.h
index d2c4adef..27ae75ce 100644
--- a/nest/route.h
+++ b/nest/route.h
@@ -244,12 +244,6 @@ typedef struct rte {
   byte pflags;				/* Protocol-specific flags */
   btime lastmod;			/* Last modified */
   union {				/* Protocol-dependent data (metrics etc.) */
-#ifdef CONFIG_BGP
-    struct {
-      u8 suppressed;			/* Used for deterministic MED comparison */
-      s8 stale;				/* Route is LLGR_STALE, -1 if unknown */
-    } bgp;
-#endif
   } u;
 } rte;
 
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 18d2985c..0ed2623e 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -1887,14 +1887,24 @@ bgp_get_neighbor(rte *r)
 static inline int
 rte_stale(rte *r)
 {
-  if (r->u.bgp.stale < 0)
-  {
-    /* If staleness is unknown, compute and cache it */
-    eattr *a = ea_find(r->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_COMMUNITY));
-    r->u.bgp.stale = a && int_set_contains(a->u.ptr, BGP_COMM_LLGR_STALE);
-  }
+  if (r->pflags & BGP_REF_STALE)
+    return 1;
 
-  return r->u.bgp.stale;
+  if (r->pflags & BGP_REF_NOT_STALE)
+    return 0;
+
+  /* If staleness is unknown, compute and cache it */
+  eattr *a = ea_find(r->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_COMMUNITY));
+  if (a && int_set_contains(a->u.ptr, BGP_COMM_LLGR_STALE))
+  {
+    r->pflags |= BGP_REF_STALE;
+    return 1;
+  }
+  else
+  {
+    r->pflags |= BGP_REF_NOT_STALE;
+    return 0;
+  }
 }
 
 int
@@ -1906,8 +1916,8 @@ bgp_rte_better(rte *new, rte *old)
   u32 n, o;
 
   /* Skip suppressed routes (see bgp_rte_recalculate()) */
-  n = new->u.bgp.suppressed;
-  o = old->u.bgp.suppressed;
+  n = new->pflags & BGP_REF_SUPPRESSED;
+  o = old->pflags & BGP_REF_SUPPRESSED;
   if (n > o)
     return 0;
   if (n < o)
@@ -2051,17 +2061,14 @@ bgp_rte_mergable(rte *pri, rte *sec)
   u32 p, s;
 
   /* Skip suppressed routes (see bgp_rte_recalculate()) */
-  if (pri->u.bgp.suppressed != sec->u.bgp.suppressed)
+  /* LLGR draft - depreference stale routes */
+  if (pri->pflags != sec->pflags)
     return 0;
 
   /* RFC 4271 9.1.2.1. Route resolvability test */
   if (rte_resolvable(pri) != rte_resolvable(sec))
     return 0;
 
-  /* LLGR draft - depreference stale routes */
-  if (rte_stale(pri) != rte_stale(sec))
-    return 0;
-
   /* Start with local preferences */
   x = ea_find(pri->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
   y = ea_find(sec->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
@@ -2141,7 +2148,7 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
   rte *key = new ? new : old;
   u32 lpref = key->attrs->pref;
   u32 lasn = bgp_get_neighbor(key);
-  int old_suppressed = old ? old->u.bgp.suppressed : 0;
+  int old_suppressed = old ? !!(old->pflags & BGP_REF_SUPPRESSED) : 0;
 
   /*
    * Proper RFC 4271 path selection is a bit complicated, it cannot be
@@ -2193,11 +2200,11 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
    */
 
   if (new)
-    new->u.bgp.suppressed = 1;
+    new->pflags |= BGP_REF_SUPPRESSED;
 
   if (old)
   {
-    old->u.bgp.suppressed = 1;
+    old->pflags |= BGP_REF_SUPPRESSED;
 
     /* The fast case - replace not best with worse (or remove not best) */
     if (old_suppressed && !(new && bgp_rte_better(new, old)))
@@ -2209,7 +2216,7 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
   for (s=net->routes; rte_is_valid(s); s=s->next)
     if (use_deterministic_med(s) && same_group(s, lpref, lasn))
     {
-      s->u.bgp.suppressed = 1;
+      s->pflags |= BGP_REF_SUPPRESSED;
       if (!r || bgp_rte_better(s, r))
 	r = s;
     }
@@ -2220,16 +2227,16 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
 
   /* Found if new is mergable with best-in-group */
   if (new && (new != r) && bgp_rte_mergable(r, new))
-    new->u.bgp.suppressed = 0;
+    new->pflags &= ~BGP_REF_SUPPRESSED;
 
   /* Found all existing routes mergable with best-in-group */
   for (s=net->routes; rte_is_valid(s); s=s->next)
     if (use_deterministic_med(s) && same_group(s, lpref, lasn))
       if ((s != r) && bgp_rte_mergable(r, s))
-	s->u.bgp.suppressed = 0;
+	s->pflags &= ~BGP_REF_SUPPRESSED;
 
   /* Found best-in-group */
-  r->u.bgp.suppressed = 0;
+  r->pflags &= ~BGP_REF_SUPPRESSED;
 
   /*
    * There are generally two reasons why we have to force
@@ -2277,7 +2284,7 @@ bgp_rte_modify_stale(struct rte *r, struct linpool *pool)
   r = rte_cow_rta(r, pool);
   bgp_set_attr_ptr(&(r->attrs->eattrs), pool, BA_COMMUNITY, flags,
 		   int_set_add(pool, ad, BGP_COMM_LLGR_STALE));
-  r->u.bgp.stale = 1;
+  r->pflags |= BGP_REF_STALE;
 
   return r;
 }
@@ -2364,7 +2371,7 @@ bgp_get_route_info(rte *e, byte *buf)
 
   buf += bsprintf(buf, " (%d", e->attrs->pref);
 
-  if (e->u.bgp.suppressed)
+  if (e->pflags & BGP_REF_SUPPRESSED)
     buf += bsprintf(buf, "-");
 
   if (rte_stale(e))
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index c440c7af..b770956b 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -200,6 +200,10 @@ struct bgp_channel_config {
 
 #define BGP_BFD_GRACEFUL	2	/* BFD down triggers graceful restart */
 
+/* rte->pflags */
+#define BGP_REF_SUPPRESSED	0x1	/* Used for deterministic MED comparison */
+#define BGP_REF_STALE		0x2	/* Route is LLGR_STATE */
+#define BGP_REF_NOT_STALE	0x4	/* Route is NOT LLGR_STATE */
 
 struct bgp_af_caps {
   u32 afi;
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index b8d80513..6bc71623 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -1366,8 +1366,6 @@ bgp_rte_update(struct bgp_parse_state *s, net_addr *n, u32 path_id, rta *a0)
   rte *e = rte_get_temp(a, s->last_src);
 
   e->pflags = 0;
-  e->u.bgp.suppressed = 0;
-  e->u.bgp.stale = -1;
   rte_update3(&s->channel->c, n, e, s->last_src);
 }
 
diff --git a/proto/pipe/pipe.c b/proto/pipe/pipe.c
index de86b62b..d85a281a 100644
--- a/proto/pipe/pipe.c
+++ b/proto/pipe/pipe.c
@@ -43,6 +43,10 @@
 
 #include "pipe.h"
 
+#ifdef CONFIG_BGP
+#include "proto/bgp/bgp.h"
+#endif
+
 static void
 pipe_rt_notify(struct proto *P, struct channel *src_ch, net *n, rte *new, rte *old)
 {
@@ -82,7 +86,7 @@ pipe_rt_notify(struct proto *P, struct channel *src_ch, net *n, rte *new, rte *o
 #ifdef CONFIG_BGP
       /* Hack to cleanup cached value */
       if (e->src->proto->proto == &proto_bgp)
-	e->u.bgp.stale = -1;
+	e->pflags &= ~(BGP_REF_STALE | BGP_REF_NOT_STALE);
 #endif
     }
   else