bgpd: Convert the bgp_advertise_attr->adv to a fifo

BGP is storing outgoing updates in a couple of different
fifo's.  This is to ensure proper packet packing of
all bgp_dests that happen to use the same attribute.

How it's all put together currently:  On initial update
BGP walks through all the bgp_dest's in a table.  For each
path being sent a bgp_advertise is created.  This bgp_advertise
is placed in fifo order on the bgp_synchronize->update queue.
The bgp_advertise has a pointer to the bgp_advertise_attr which
is associated iwth the actual attribute that is being sent to
it's peer.  In turn this bgp_advertise is placed in a fifo off
of the bgp_advertise_attr structure.  As such as we have paths
that share an attribute, the path/dest is placed on the
bgp_syncrhonize->update fifo as well as being placed on the fifo
associated with the advertised attribute.

On actual creation of a packet.  The first item in the
bgp_synchronize->update fifo is popped.  The bgp_advertise_attr
pointer is grabbed, we fill out the nlri part of the bgp packet
and then walk the bgp_advertise_attr fifo to place paths/dests in
the packet.  As each path/dest is placed in the packet it is removed
from both the bgp_synchronize->update fifo and the bgp_advertise_attr
fifo.

The whole point of this change is to switch the *next, *prev
pointers in the bgp_advertise structure with a typesafe data
structure.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>
(cherry picked from commit b2e0c12d723a6464f67491ceb912225f35c9427a)

# Conflicts:
#	bgpd/bgp_advertise.c

diff --git a/bgpd/bgp_advertise.c b/bgpd/bgp_advertise.c
index da7b496d65f29f502aabd6857c32a5c1c34bfe0d..7abb49a07ab46bca48532591cd4601059a91f70e 100644 (file)
--- a/bgpd/bgp_advertise.c
+++ b/bgpd/bgp_advertise.c
@@ -36,6 +36,8 @@ struct bgp_advertise_attr *bgp_advertise_attr_new(void)
 
 void bgp_advertise_attr_free(struct bgp_advertise_attr *baa)
 {
+       bgp_advertise_attr_fifo_fini(&baa->fifo);
+
        XFREE(MTYPE_BGP_ADVERTISE_ATTR, baa);
 }
 
@@ -46,6 +48,9 @@ static void *bgp_advertise_attr_hash_alloc(void *p)
 
        baa = bgp_advertise_attr_new();
        baa->attr = ref->attr;
+
+       bgp_advertise_attr_fifo_init(&baa->fifo);
+
        return baa;
 }
 
@@ -83,21 +88,13 @@ void bgp_advertise_free(struct bgp_advertise *adv)
 void bgp_advertise_add(struct bgp_advertise_attr *baa,
                       struct bgp_advertise *adv)
 {
-       adv->next = baa->adv;
-       if (baa->adv)
-               baa->adv->prev = adv;
-       baa->adv = adv;
+       bgp_advertise_attr_fifo_add_tail(&baa->fifo, adv);
 }
 
 void bgp_advertise_delete(struct bgp_advertise_attr *baa,
                          struct bgp_advertise *adv)
 {
-       if (adv->next)
-               adv->next->prev = adv->prev;
-       if (adv->prev)
-               adv->prev->next = adv->next;
-       else
-               baa->adv = adv->next;
+       bgp_advertise_attr_fifo_del(&baa->fifo, adv);
 }
 
 struct bgp_advertise_attr *bgp_advertise_attr_intern(struct hash *hash,

diff --git a/bgpd/bgp_advertise.h b/bgpd/bgp_advertise.h
index a063208b6d10a3c379c4cdcffbc0bfac2e06dc96..04271b5309e1f7ef9fcdb329d9a6462d8e883cfd 100644 (file)
--- a/bgpd/bgp_advertise.h
+++ b/bgpd/bgp_advertise.h
@@ -11,26 +11,19 @@
 PREDECL_DLIST(bgp_adv_fifo);
 
 struct update_subgroup;
+struct bgp_advertise;
 
-/* BGP advertise attribute.  */
-struct bgp_advertise_attr {
-       /* Head of advertisement pointer. */
-       struct bgp_advertise *adv;
+PREDECL_DLIST(bgp_advertise_attr_fifo);
 
-       /* Reference counter.  */
-       unsigned long refcnt;
-
-       /* Attribute pointer to be announced.  */
-       struct attr *attr;
-};
+struct bgp_advertise_attr;
 
+/* BGP advertise attribute.  */
 struct bgp_advertise {
        /* FIFO for advertisement.  */
        struct bgp_adv_fifo_item fifo;
 
-       /* Link list for same attribute advertise.  */
-       struct bgp_advertise *next;
-       struct bgp_advertise *prev;
+       /* FIFO for this item in the bgp_advertise_attr fifo */
+       struct bgp_advertise_attr_fifo_item item;
 
        /* Prefix information.  */
        struct bgp_dest *dest;
@@ -45,8 +38,21 @@ struct bgp_advertise {
        struct bgp_path_info *pathi;
 };
 
+DECLARE_DLIST(bgp_advertise_attr_fifo, struct bgp_advertise, item);
 DECLARE_DLIST(bgp_adv_fifo, struct bgp_advertise, fifo);
 
+/* BGP advertise attribute.  */
+struct bgp_advertise_attr {
+       /* Head of advertisement pointer. */
+       struct bgp_advertise_attr_fifo_head fifo;
+
+       /* Reference counter.  */
+       unsigned long refcnt;
+
+       /* Attribute pointer to be announced.  */
+       struct attr *attr;
+};
+
 /* BGP adjacency out.  */
 struct bgp_adj_out {
        /* RB Tree of adjacency entries */

diff --git a/bgpd/bgp_updgrp_adv.c b/bgpd/bgp_updgrp_adv.c
index 2516a4e1c4864b2c70ba278b02756429f39b7455..89469ffee3d871412761f29f2772cb0f2a26fa3c 100644 (file)
--- a/bgpd/bgp_updgrp_adv.c
+++ b/bgpd/bgp_updgrp_adv.c
@@ -426,7 +426,7 @@ bgp_advertise_clean_subgroup(struct update_subgroup *subgrp,
                bgp_advertise_delete(baa, adv);
 
                /* Fetch next advertise candidate. */
-               next = baa->adv;
+               next = bgp_advertise_attr_fifo_first(&baa->fifo);
 
                /* Unintern BGP advertise attribute.  */
                bgp_advertise_attr_unintern(subgrp->hash, baa);