bgpd: Optimize the path for suppressed announcements

If supress-duplicates is turned of (which is turned on by default), do not calculate attribute hash key, that consumes CPU quite a lot. Signed-off-by: Donatas Abraitis <[email protected]>
FRRouting · Mar 26, 2024 · 59571fd · 59571fd
1 parent 0b1af4c
commit 59571fd
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/bgpd/bgp_updgrp_adv.c b/bgpd/bgp_updgrp_adv.c
@@ -532,7 +532,7 @@ bool bgp_adj_out_set_subgroup(struct bgp_dest *dest,
 	struct peer *adv_peer;
 	struct peer_af *paf;
 	struct bgp *bgp;
-	uint32_t attr_hash = attrhash_key_make(attr);
+	uint32_t attr_hash = 0;
 
 	peer = SUBGRP_PEER(subgrp);
 	afi = SUBGRP_AFI(subgrp);
@@ -567,9 +567,11 @@ bool bgp_adj_out_set_subgroup(struct bgp_dest *dest,
 	 * the route wasn't changed actually.
 	 * Do not suppress BGP UPDATES for route-refresh.
 	 */
-	if (CHECK_FLAG(bgp->flags, BGP_FLAG_SUPPRESS_DUPLICATES)
-	    && !CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_FORCE_UPDATES)
-	    && adj->attr_hash == attr_hash) {
+	if (likely(CHECK_FLAG(bgp->flags, BGP_FLAG_SUPPRESS_DUPLICATES)))
+		attr_hash = attrhash_key_make(attr);
+
+	if (!CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_FORCE_UPDATES) &&
+	    attr_hash && adj->attr_hash == attr_hash) {
 		if (BGP_DEBUG(update, UPDATE_OUT)) {
 			char attr_str[BUFSIZ] = {0};