From 8ff56318a8bd188cfcc1cdab689c46c326b50d38 Mon Sep 17 00:00:00 2001 From: "Jorge Boncompte [DTI2]" Date: Mon, 7 May 2012 16:52:56 +0000 Subject: bgpd: optimize bgp_info_cmp() * bgp_route.c: (bgp_info_cmp) Reduce indirections, precalculate some values that are used several times, reduce conditionals. Signed-off-by: Jorge Boncompte [DTI2] Signed-off-by: David Lamparter --- bgpd/bgp_route.c | 151 ++++++++++++++++++++++++++++--------------------------- 1 file changed, 77 insertions(+), 74 deletions(-) (limited to 'bgpd') diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c index f80bcfa9..cb15c152 100644 --- a/bgpd/bgp_route.c +++ b/bgpd/bgp_route.c @@ -322,20 +322,24 @@ static int bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, int *paths_eq) { + struct attr *newattr, *existattr; + struct attr_extra *newattre, *existattre; + bgp_peer_sort_t new_sort; + bgp_peer_sort_t exist_sort; u_int32_t new_pref; u_int32_t exist_pref; u_int32_t new_med; u_int32_t exist_med; - u_int32_t new_weight = 0; - u_int32_t exist_weight = 0; + u_int32_t new_weight; + u_int32_t exist_weight; + uint32_t newm, existm; struct in_addr new_id; struct in_addr exist_id; int new_cluster; int exist_cluster; - int internal_as_route = 0; - int confed_as_route = 0; + int internal_as_route; + int confed_as_route; int ret; - uint32_t newm, existm; *paths_eq = 0; @@ -345,60 +349,59 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, if (exist == NULL) return 1; + newattr = new->attr; + existattr = exist->attr; + newattre = newattr->extra; + existattre = existattr->extra; + /* 1. Weight check. */ - if (new->attr->extra) - new_weight = new->attr->extra->weight; - if (exist->attr->extra) - exist_weight = exist->attr->extra->weight; + new_weight = exist_weight = 0; + + if (newattre) + new_weight = newattre->weight; + if (existattre) + exist_weight = existattre->weight; + if (new_weight > exist_weight) return 1; if (new_weight < exist_weight) return 0; /* 2. Local preference check. */ - if (new->attr->flag & ATTR_FLAG_BIT (BGP_ATTR_LOCAL_PREF)) - new_pref = new->attr->local_pref; - else - new_pref = bgp->default_local_pref; + new_pref = exist_pref = bgp->default_local_pref; + + if (newattr->flag & ATTR_FLAG_BIT (BGP_ATTR_LOCAL_PREF)) + new_pref = newattr->local_pref; + if (existattr->flag & ATTR_FLAG_BIT (BGP_ATTR_LOCAL_PREF)) + exist_pref = existattr->local_pref; - if (exist->attr->flag & ATTR_FLAG_BIT (BGP_ATTR_LOCAL_PREF)) - exist_pref = exist->attr->local_pref; - else - exist_pref = bgp->default_local_pref; - if (new_pref > exist_pref) return 1; if (new_pref < exist_pref) return 0; - /* 3. Local route check. */ - if (new->sub_type == BGP_ROUTE_STATIC) - return 1; - if (exist->sub_type == BGP_ROUTE_STATIC) - return 0; - - if (new->sub_type == BGP_ROUTE_REDISTRIBUTE) - return 1; - if (exist->sub_type == BGP_ROUTE_REDISTRIBUTE) - return 0; - - if (new->sub_type == BGP_ROUTE_AGGREGATE) - return 1; - if (exist->sub_type == BGP_ROUTE_AGGREGATE) - return 0; + /* 3. Local route check. We prefer: + * - BGP_ROUTE_STATIC + * - BGP_ROUTE_AGGREGATE + * - BGP_ROUTE_REDISTRIBUTE + */ + if (! (new->sub_type == BGP_ROUTE_NORMAL)) + return 1; + if (! (exist->sub_type == BGP_ROUTE_NORMAL)) + return 0; /* 4. AS path length check. */ if (! bgp_flag_check (bgp, BGP_FLAG_ASPATH_IGNORE)) { - int exist_hops = aspath_count_hops (exist->attr->aspath); - int exist_confeds = aspath_count_confeds (exist->attr->aspath); + int exist_hops = aspath_count_hops (existattr->aspath); + int exist_confeds = aspath_count_confeds (existattr->aspath); if (bgp_flag_check (bgp, BGP_FLAG_ASPATH_CONFED)) { int aspath_hops; - aspath_hops = aspath_count_hops (new->attr->aspath); - aspath_hops += aspath_count_confeds (new->attr->aspath); + aspath_hops = aspath_count_hops (newattr->aspath); + aspath_hops += aspath_count_confeds (newattr->aspath); if ( aspath_hops < (exist_hops + exist_confeds)) return 1; @@ -407,7 +410,7 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, } else { - int newhops = aspath_count_hops (new->attr->aspath); + int newhops = aspath_count_hops (newattr->aspath); if (newhops < exist_hops) return 1; @@ -417,24 +420,24 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, } /* 5. Origin check. */ - if (new->attr->origin < exist->attr->origin) + if (newattr->origin < existattr->origin) return 1; - if (new->attr->origin > exist->attr->origin) + if (newattr->origin > existattr->origin) return 0; /* 6. MED check. */ - internal_as_route = (aspath_count_hops (new->attr->aspath) == 0 - && aspath_count_hops (exist->attr->aspath) == 0); - confed_as_route = (aspath_count_confeds (new->attr->aspath) > 0 - && aspath_count_confeds (exist->attr->aspath) > 0 - && aspath_count_hops (new->attr->aspath) == 0 - && aspath_count_hops (exist->attr->aspath) == 0); + internal_as_route = (aspath_count_hops (newattr->aspath) == 0 + && aspath_count_hops (existattr->aspath) == 0); + confed_as_route = (aspath_count_confeds (newattr->aspath) > 0 + && aspath_count_confeds (existattr->aspath) > 0 + && aspath_count_hops (newattr->aspath) == 0 + && aspath_count_hops (existattr->aspath) == 0); if (bgp_flag_check (bgp, BGP_FLAG_ALWAYS_COMPARE_MED) || (bgp_flag_check (bgp, BGP_FLAG_MED_CONFED) && confed_as_route) - || aspath_cmp_left (new->attr->aspath, exist->attr->aspath) - || aspath_cmp_left_confed (new->attr->aspath, exist->attr->aspath) + || aspath_cmp_left (newattr->aspath, existattr->aspath) + || aspath_cmp_left_confed (newattr->aspath, existattr->aspath) || internal_as_route) { new_med = bgp_med_value (new->attr, bgp); @@ -447,22 +450,24 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, } /* 7. Peer type check. */ - if (new->peer->sort == BGP_PEER_EBGP - && exist->peer->sort == BGP_PEER_IBGP) - return 1; - if (new->peer->sort == BGP_PEER_EBGP - && exist->peer->sort == BGP_PEER_CONFED) + new_sort = new->peer->sort; + exist_sort = exist->peer->sort; + + if (new_sort == BGP_PEER_EBGP + && (exist_sort == BGP_PEER_IBGP || exist_sort == BGP_PEER_CONFED)) return 1; - if (new->peer->sort == BGP_PEER_IBGP - && exist->peer->sort == BGP_PEER_EBGP) - return 0; - if (new->peer->sort == BGP_PEER_CONFED - && exist->peer->sort == BGP_PEER_EBGP) + if (exist_sort == BGP_PEER_EBGP + && (new_sort == BGP_PEER_IBGP || new_sort == BGP_PEER_CONFED)) return 0; /* 8. IGP metric check. */ - newm = (new->extra ? new->extra->igpmetric : 0); - existm = (exist->extra ? exist->extra->igpmetric : 0); + newm = existm = 0; + + if (new->extra) + newm = new->extra->igpmetric; + if (exist->extra) + existm = exist->extra->igpmetric; + if (newm < existm) ret = 1; if (newm > existm) @@ -493,8 +498,8 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, newer path won't displace an older one, even if it was the preferred route based on the additional decision criteria below. */ if (! bgp_flag_check (bgp, BGP_FLAG_COMPARE_ROUTER_ID) - && new->peer->sort == BGP_PEER_EBGP - && exist->peer->sort == BGP_PEER_EBGP) + && new_sort == BGP_PEER_EBGP + && exist_sort == BGP_PEER_EBGP) { if (CHECK_FLAG (new->flags, BGP_INFO_SELECTED)) return 1; @@ -503,12 +508,12 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, } /* 11. Rourter-ID comparision. */ - if (new->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID)) - new_id.s_addr = new->attr->extra->originator_id.s_addr; + if (newattr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID)) + new_id.s_addr = newattre->originator_id.s_addr; else new_id.s_addr = new->peer->remote_id.s_addr; - if (exist->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID)) - exist_id.s_addr = exist->attr->extra->originator_id.s_addr; + if (existattr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID)) + exist_id.s_addr = existattre->originator_id.s_addr; else exist_id.s_addr = exist->peer->remote_id.s_addr; @@ -518,14 +523,12 @@ bgp_info_cmp (struct bgp *bgp, struct bgp_info *new, struct bgp_info *exist, return 0; /* 12. Cluster length comparision. */ - if (new->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST)) - new_cluster = new->attr->extra->cluster->length; - else - new_cluster = 0; - if (exist->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST)) - exist_cluster = exist->attr->extra->cluster->length; - else - exist_cluster = 0; + new_cluster = exist_cluster = 0; + + if (newattr->flag & ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST)) + new_cluster = newattre->cluster->length; + if (existattr->flag & ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST)) + exist_cluster = existattre->cluster->length; if (new_cluster < exist_cluster) return 1; -- cgit v1.2.1