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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-11-18 17:18:42 +00:00

Merge commit '97476e00' into thread-next

Had to fix route source locking inside BGP export table as we need to
keep the route sources properly allocated until even last BGP pending
update is sent out, therefore the export table printout is accurate.
This commit is contained in:
Maria Matejka 2022-08-03 14:07:53 +02:00
commit 5a96b9b124
5 changed files with 126 additions and 79 deletions

View File

@ -10,6 +10,8 @@
#ifndef _BIRD_LIB_ROUTE_H_ #ifndef _BIRD_LIB_ROUTE_H_
#define _BIRD_LIB_ROUTE_H_ #define _BIRD_LIB_ROUTE_H_
#undef RT_SOURCE_DEBUG
#include "lib/type.h" #include "lib/type.h"
#include "lib/rcu.h" #include "lib/rcu.h"
#include "lib/hash.h" #include "lib/hash.h"
@ -87,6 +89,11 @@ struct rte_src *rt_get_source_o(struct rte_owner *o, u32 id);
struct rte_src *rt_find_source_global(u32 id); struct rte_src *rt_find_source_global(u32 id);
#ifdef RT_SOURCE_DEBUG
#define rt_lock_source _rt_lock_source_internal
#define rt_unlock_source _rt_unlock_source_internal
#endif
static inline void rt_lock_source(struct rte_src *src) static inline void rt_lock_source(struct rte_src *src)
{ {
/* Locking a source is trivial; somebody already holds it so we just increase /* Locking a source is trivial; somebody already holds it so we just increase
@ -139,6 +146,14 @@ static inline void rt_unlock_source(struct rte_src *src)
rcu_read_unlock(); rcu_read_unlock();
} }
#ifdef RT_SOURCE_DEBUG
#undef rt_lock_source
#undef rt_unlock_source
#define rt_lock_source(x) ( log(L_INFO "Lock source %uG at %s:%d", (x)->global_id, __FILE__, __LINE__), _rt_lock_source_internal(x) )
#define rt_unlock_source(x) ( log(L_INFO "Unlock source %uG at %s:%d", (x)->global_id, __FILE__, __LINE__), _rt_unlock_source_internal(x) )
#endif
void rt_init_sources(struct rte_owner *, const char *name, event_list *list); void rt_init_sources(struct rte_owner *, const char *name, event_list *list);
void rt_destroy_sources(struct rte_owner *, event *); void rt_destroy_sources(struct rte_owner *, event *);

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@ -1522,8 +1522,8 @@ bgp_finish_attrs(struct bgp_parse_state *s, ea_list **to)
HASH_DEFINE_REHASH_FN(RBH, struct bgp_bucket) HASH_DEFINE_REHASH_FN(RBH, struct bgp_bucket)
void static void
bgp_init_bucket_table(struct bgp_channel *c) bgp_init_bucket_table(struct bgp_pending_tx *c)
{ {
HASH_INIT(c->bucket_hash, c->pool, 8); HASH_INIT(c->bucket_hash, c->pool, 8);
@ -1531,24 +1531,8 @@ bgp_init_bucket_table(struct bgp_channel *c)
c->withdraw_bucket = NULL; c->withdraw_bucket = NULL;
} }
void
bgp_free_bucket_table(struct bgp_channel *c)
{
HASH_FREE(c->bucket_hash);
struct bgp_bucket *b;
WALK_LIST_FIRST(b, c->bucket_queue)
{
rem_node(&b->send_node);
mb_free(b);
}
mb_free(c->withdraw_bucket);
c->withdraw_bucket = NULL;
}
static struct bgp_bucket * static struct bgp_bucket *
bgp_get_bucket(struct bgp_channel *c, ea_list *new) bgp_get_bucket(struct bgp_pending_tx *c, ea_list *new)
{ {
/* Hash and lookup */ /* Hash and lookup */
u32 hash = ea_hash(new); u32 hash = ea_hash(new);
@ -1577,7 +1561,7 @@ bgp_get_bucket(struct bgp_channel *c, ea_list *new)
} }
static struct bgp_bucket * static struct bgp_bucket *
bgp_get_withdraw_bucket(struct bgp_channel *c) bgp_get_withdraw_bucket(struct bgp_pending_tx *c)
{ {
if (!c->withdraw_bucket) if (!c->withdraw_bucket)
{ {
@ -1589,15 +1573,17 @@ bgp_get_withdraw_bucket(struct bgp_channel *c)
} }
static void static void
bgp_free_bucket_xx(struct bgp_channel *c, struct bgp_bucket *b) bgp_free_bucket(struct bgp_pending_tx *c, struct bgp_bucket *b)
{ {
HASH_REMOVE2(c->bucket_hash, RBH, c->pool, b); HASH_REMOVE2(c->bucket_hash, RBH, c->pool, b);
mb_free(b); mb_free(b);
} }
int int
bgp_done_bucket(struct bgp_channel *c, struct bgp_bucket *b) bgp_done_bucket(struct bgp_channel *bc, struct bgp_bucket *b)
{ {
struct bgp_pending_tx *c = bc->ptx;
/* Won't free the withdraw bucket */ /* Won't free the withdraw bucket */
if (b == c->withdraw_bucket) if (b == c->withdraw_bucket)
return 0; return 0;
@ -1608,21 +1594,23 @@ bgp_done_bucket(struct bgp_channel *c, struct bgp_bucket *b)
if (b->px_uc || !EMPTY_LIST(b->prefixes)) if (b->px_uc || !EMPTY_LIST(b->prefixes))
return 0; return 0;
bgp_free_bucket_xx(c, b); bgp_free_bucket(c, b);
return 1; return 1;
} }
void void
bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b) bgp_defer_bucket(struct bgp_channel *bc, struct bgp_bucket *b)
{ {
struct bgp_pending_tx *c = bc->ptx;
rem_node(&b->send_node); rem_node(&b->send_node);
add_tail(&c->bucket_queue, &b->send_node); add_tail(&c->bucket_queue, &b->send_node);
} }
void void
bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b) bgp_withdraw_bucket(struct bgp_channel *bc, struct bgp_bucket *b)
{ {
struct bgp_proto *p = (void *) c->c.proto; struct bgp_proto *p = (void *) bc->c.proto;
struct bgp_pending_tx *c = bc->ptx;
struct bgp_bucket *wb = bgp_get_withdraw_bucket(c); struct bgp_bucket *wb = bgp_get_withdraw_bucket(c);
log(L_ERR "%s: Attribute list too long", p->p.name); log(L_ERR "%s: Attribute list too long", p->p.name);
@ -1643,7 +1631,7 @@ bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b)
#define PXH_KEY(px) px->net, px->path_id, px->hash #define PXH_KEY(px) px->net, px->path_id, px->hash
#define PXH_NEXT(px) px->next #define PXH_NEXT(px) px->next
#define PXH_EQ(n1,i1,h1,n2,i2,h2) h1 == h2 && (c->add_path_tx ? (i1 == i2) : 1) && net_equal(n1, n2) #define PXH_EQ(n1,i1,h1,n2,i2,h2) h1 == h2 && (add_path_tx ? (i1 == i2) : 1) && net_equal(n1, n2)
#define PXH_FN(n,i,h) h #define PXH_FN(n,i,h) h
#define PXH_REHASH bgp_pxh_rehash #define PXH_REHASH bgp_pxh_rehash
@ -1652,29 +1640,21 @@ bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b)
HASH_DEFINE_REHASH_FN(PXH, struct bgp_prefix) HASH_DEFINE_REHASH_FN(PXH, struct bgp_prefix)
void static void
bgp_init_prefix_table(struct bgp_channel *c) bgp_init_prefix_table(struct bgp_channel *bc)
{ {
struct bgp_pending_tx *c = bc->ptx;
HASH_INIT(c->prefix_hash, c->pool, 8); HASH_INIT(c->prefix_hash, c->pool, 8);
uint alen = net_addr_length[c->c.net_type]; uint alen = net_addr_length[bc->c.net_type];
c->prefix_slab = alen ? sl_new(c->pool, sizeof(struct bgp_prefix) + alen) : NULL; c->prefix_slab = alen ? sl_new(c->pool, sizeof(struct bgp_prefix) + alen) : NULL;
} }
void
bgp_free_prefix_table(struct bgp_channel *c)
{
HASH_FREE(c->prefix_hash);
rfree(c->prefix_slab);
c->prefix_slab = NULL;
}
static struct bgp_prefix * static struct bgp_prefix *
bgp_get_prefix(struct bgp_channel *c, const net_addr *net, struct rte_src *src) bgp_get_prefix(struct bgp_pending_tx *c, const net_addr *net, struct rte_src *src, int add_path_tx)
{ {
u32 path_id = src->global_id; u32 path_id = src->global_id;
u32 path_id_hash = c->add_path_tx ? path_id : 0; u32 path_id_hash = add_path_tx ? path_id : 0;
/* We must use a different hash function than the rtable */ /* We must use a different hash function than the rtable */
u32 hash = u32_hash(net_hash(net) ^ u32_hash(path_id_hash)); u32 hash = u32_hash(net_hash(net) ^ u32_hash(path_id_hash));
struct bgp_prefix *px = HASH_FIND(c->prefix_hash, PXH, net, path_id_hash, hash); struct bgp_prefix *px = HASH_FIND(c->prefix_hash, PXH, net, path_id_hash, hash);
@ -1698,15 +1678,16 @@ bgp_get_prefix(struct bgp_channel *c, const net_addr *net, struct rte_src *src)
return px; return px;
} }
static void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *px); static void bgp_free_prefix(struct bgp_pending_tx *c, struct bgp_prefix *px);
static inline int static inline int
bgp_update_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket *b) bgp_update_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket *b)
{ {
#define IS_WITHDRAW_BUCKET(b) ((b) == c->ptx->withdraw_bucket)
#define BPX_TRACE(what) do { \ #define BPX_TRACE(what) do { \
if (c->c.debug & D_ROUTES) log(L_TRACE "%s.%s < %s %N %uG %s", \ if (c->c.debug & D_ROUTES) log(L_TRACE "%s.%s < %s %N %uG %s", \
c->c.proto->name, c->c.name, what, \ c->c.proto->name, c->c.name, what, \
px->net, px->path_id, (b == c->withdraw_bucket) ? "withdraw" : "update"); } while (0) px->net, px->path_id, IS_WITHDRAW_BUCKET(b) ? "withdraw" : "update"); } while (0)
px->lastmod = current_time(); px->lastmod = current_time();
/* Already queued for the same bucket */ /* Already queued for the same bucket */
@ -1724,7 +1705,7 @@ bgp_update_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucke
} }
/* The new bucket is the same as we sent before */ /* The new bucket is the same as we sent before */
if ((px->last == b) || c->c.out_table && !px->last && (b == c->withdraw_bucket)) if ((px->last == b) || c->c.out_table && !px->last && IS_WITHDRAW_BUCKET(b))
{ {
if (px->cur) if (px->cur)
BPX_TRACE("reverted"); BPX_TRACE("reverted");
@ -1733,15 +1714,15 @@ bgp_update_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucke
/* Well, we haven't sent anything yet */ /* Well, we haven't sent anything yet */
if (!px->last) if (!px->last)
bgp_free_prefix(c, px); bgp_free_prefix(c->ptx, px);
px->cur = NULL; px->cur = NULL;
return 0; return 0;
} }
/* Enqueue the bucket if it has been empty */ /* Enqueue the bucket if it has been empty */
if ((b != c->withdraw_bucket) && EMPTY_LIST(b->prefixes)) if (!IS_WITHDRAW_BUCKET(b) && EMPTY_LIST(b->prefixes))
add_tail(&c->bucket_queue, &b->send_node); add_tail(&c->ptx->bucket_queue, &b->send_node);
/* Enqueue to the new bucket and indicate the change */ /* Enqueue to the new bucket and indicate the change */
add_tail(&b->prefixes, &px->buck_node_xx); add_tail(&b->prefixes, &px->buck_node_xx);
@ -1754,7 +1735,7 @@ bgp_update_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucke
} }
static void static void
bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *px) bgp_free_prefix(struct bgp_pending_tx *c, struct bgp_prefix *px)
{ {
HASH_REMOVE2(c->prefix_hash, PXH, c->pool, px); HASH_REMOVE2(c->prefix_hash, PXH, c->pool, px);
@ -1784,7 +1765,7 @@ bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket
px->last->px_uc--; px->last->px_uc--;
/* Ref the current sent version */ /* Ref the current sent version */
if (buck != c->withdraw_bucket) if (!IS_WITHDRAW_BUCKET(buck))
{ {
px->last = buck; px->last = buck;
px->last->px_uc++; px->last->px_uc++;
@ -1794,7 +1775,49 @@ bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket
/* Prefixes belonging to the withdraw bucket are freed always */ /* Prefixes belonging to the withdraw bucket are freed always */
} }
bgp_free_prefix(c, px); bgp_free_prefix(c->ptx, px);
}
static void
bgp_pending_tx_rfree(resource *r)
{
struct bgp_pending_tx *ptx = SKIP_BACK(struct bgp_pending_tx, r, r);
HASH_WALK(ptx->prefix_hash, next, n)
rt_unlock_source(rt_find_source_global(n->path_id));
HASH_WALK_END;
}
static void bgp_pending_tx_dump(resource *r UNUSED) { debug("\n"); }
static struct resclass bgp_pending_tx_class = {
.name = "BGP Pending TX",
.size = sizeof(struct bgp_pending_tx),
.free = bgp_pending_tx_rfree,
.dump = bgp_pending_tx_dump,
};
void
bgp_init_pending_tx(struct bgp_channel *c)
{
ASSERT_DIE(!c->ptx);
pool *p = rp_new(c->pool, "BGP Pending TX");
c->ptx = ralloc(p, &bgp_pending_tx_class);
c->ptx->pool = p;
bgp_init_bucket_table(c->ptx);
bgp_init_prefix_table(c);
}
void
bgp_free_pending_tx(struct bgp_channel *c)
{
ASSERT_DIE(c->ptx);
ASSERT_DIE(c->ptx->pool);
rfree(c->ptx->pool);
c->ptx = NULL;
} }
@ -1806,7 +1829,8 @@ static void
bgp_out_table_feed(void *data) bgp_out_table_feed(void *data)
{ {
struct rt_export_hook *hook = data; struct rt_export_hook *hook = data;
struct bgp_channel *c = SKIP_BACK(struct bgp_channel, prefix_exporter, hook->table); struct bgp_channel *bc = SKIP_BACK(struct bgp_channel, prefix_exporter, hook->table);
struct bgp_pending_tx *c = bc->ptx;
int max = 512; int max = 512;
@ -1901,8 +1925,8 @@ bgp_out_table_feed(void *data)
static struct rt_export_hook * static struct rt_export_hook *
bgp_out_table_export_start(struct rt_exporter *re, struct rt_export_request *req UNUSED) bgp_out_table_export_start(struct rt_exporter *re, struct rt_export_request *req UNUSED)
{ {
struct bgp_channel *c = SKIP_BACK(struct bgp_channel, prefix_exporter, re); struct bgp_channel *bc = SKIP_BACK(struct bgp_channel, prefix_exporter, re);
pool *p = rp_new(c->c.proto->pool, "Export hook"); pool *p = rp_new(bc->c.proto->pool, "Export hook");
struct rt_export_hook *hook = mb_allocz(p, sizeof(struct rt_export_hook)); struct rt_export_hook *hook = mb_allocz(p, sizeof(struct rt_export_hook));
hook->pool = p; hook->pool = p;
hook->event = ev_new_init(p, bgp_out_table_feed, hook); hook->event = ev_new_init(p, bgp_out_table_feed, hook);
@ -2134,16 +2158,16 @@ bgp_rt_notify(struct proto *P, struct channel *C, const net_addr *n, rte *new, c
log(L_ERR "%s: Invalid route %N withdrawn", p->p.name, n); log(L_ERR "%s: Invalid route %N withdrawn", p->p.name, n);
/* If attributes are invalid, we fail back to withdraw */ /* If attributes are invalid, we fail back to withdraw */
buck = attrs ? bgp_get_bucket(c, attrs) : bgp_get_withdraw_bucket(c); buck = attrs ? bgp_get_bucket(c->ptx, attrs) : bgp_get_withdraw_bucket(c->ptx);
path = new->src; path = new->src;
} }
else else
{ {
buck = bgp_get_withdraw_bucket(c); buck = bgp_get_withdraw_bucket(c->ptx);
path = old->src; path = old->src;
} }
if (bgp_update_prefix(c, bgp_get_prefix(c, n, path), buck)) if (bgp_update_prefix(c, bgp_get_prefix(c->ptx, n, path, c->add_path_tx), buck))
bgp_schedule_packet(p->conn, c, PKT_UPDATE); bgp_schedule_packet(p->conn, c, PKT_UPDATE);
} }

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@ -518,6 +518,12 @@ bgp_stop(struct bgp_proto *p, int subcode, byte *data, uint len)
p->uncork_ev->data = NULL; p->uncork_ev->data = NULL;
bgp_graceful_close_conn(&p->outgoing_conn, subcode, data, len); bgp_graceful_close_conn(&p->outgoing_conn, subcode, data, len);
bgp_graceful_close_conn(&p->incoming_conn, subcode, data, len); bgp_graceful_close_conn(&p->incoming_conn, subcode, data, len);
struct bgp_channel *c;
WALK_LIST(c, p->p.channels)
if (c->ptx)
bgp_free_pending_tx(c);
ev_schedule(p->event); ev_schedule(p->event);
} }
@ -787,10 +793,8 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
} }
/* Reset bucket and prefix tables */ /* Reset bucket and prefix tables */
bgp_free_bucket_table(c); bgp_free_pending_tx(c);
bgp_free_prefix_table(c); bgp_init_pending_tx(c);
bgp_init_bucket_table(c);
bgp_init_prefix_table(c);
c->packets_to_send = 0; c->packets_to_send = 0;
} }
@ -1806,8 +1810,7 @@ bgp_channel_start(struct channel *C)
if (c->cf->export_table) if (c->cf->export_table)
bgp_setup_out_table(c); bgp_setup_out_table(c);
bgp_init_bucket_table(c); bgp_init_pending_tx(c);
bgp_init_prefix_table(c);
c->stale_timer = tm_new_init(c->pool, bgp_long_lived_stale_timeout, c, 0, 0); c->stale_timer = tm_new_init(c->pool, bgp_long_lived_stale_timeout, c, 0, 0);

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@ -351,14 +351,8 @@ struct bgp_channel {
/* Rest are zeroed when down */ /* Rest are zeroed when down */
pool *pool; pool *pool;
HASH(struct bgp_bucket) bucket_hash; /* Hash table of route buckets */ struct bgp_pending_tx *ptx; /* Routes waiting to be sent */
struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */ struct rt_exporter prefix_exporter; /* Table-like exporter for ptx */
list bucket_queue; /* Queue of buckets to send (struct bgp_bucket) */
HASH(struct bgp_prefix) prefix_hash; /* Prefixes to be sent */
slab *prefix_slab; /* Slab holding prefix nodes */
struct rt_exporter prefix_exporter; /* Table-like exporter for prefix_hash */
ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */ ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
ip_addr link_addr; /* Link-local version of next_hop_addr */ ip_addr link_addr; /* Link-local version of next_hop_addr */
@ -401,6 +395,18 @@ struct bgp_bucket {
ea_list eattrs[0]; /* Per-bucket extended attributes */ ea_list eattrs[0]; /* Per-bucket extended attributes */
}; };
struct bgp_pending_tx {
resource r;
pool *pool;
HASH(struct bgp_bucket) bucket_hash; /* Hash table of route buckets */
struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */
list bucket_queue; /* Queue of buckets to send (struct bgp_bucket) */
HASH(struct bgp_prefix) prefix_hash; /* Prefixes to be sent */
slab *prefix_slab; /* Slab holding prefix nodes */
};
struct bgp_export_state { struct bgp_export_state {
struct bgp_proto *proto; struct bgp_proto *proto;
struct bgp_channel *channel; struct bgp_channel *channel;
@ -567,13 +573,12 @@ void bgp_finish_attrs(struct bgp_parse_state *s, ea_list **to);
void bgp_setup_out_table(struct bgp_channel *c); void bgp_setup_out_table(struct bgp_channel *c);
void bgp_init_bucket_table(struct bgp_channel *c); void bgp_init_pending_tx(struct bgp_channel *c);
void bgp_free_bucket_table(struct bgp_channel *c); void bgp_free_pending_tx(struct bgp_channel *c);
void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b); void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
int bgp_done_bucket(struct bgp_channel *c, struct bgp_bucket *b); int bgp_done_bucket(struct bgp_channel *c, struct bgp_bucket *b);
void bgp_init_prefix_table(struct bgp_channel *c);
void bgp_free_prefix_table(struct bgp_channel *c);
void bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket *buck); void bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket *buck);
int bgp_rte_better(struct rte *, struct rte *); int bgp_rte_better(struct rte *, struct rte *);

View File

@ -2169,7 +2169,7 @@ bgp_create_ip_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *bu
* var IPv4 Network Layer Reachability Information * var IPv4 Network Layer Reachability Information
*/ */
ASSERT_DIE(s->channel->withdraw_bucket != buck); ASSERT_DIE(s->channel->ptx->withdraw_bucket != buck);
int lr, la; int lr, la;
@ -2192,7 +2192,7 @@ bgp_create_ip_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *bu
static byte * static byte *
bgp_create_mp_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end) bgp_create_mp_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
{ {
ASSERT_DIE(s->channel->withdraw_bucket != buck); ASSERT_DIE(s->channel->ptx->withdraw_bucket != buck);
/* /*
* 2 B IPv4 Withdrawn Routes Length (zero) * 2 B IPv4 Withdrawn Routes Length (zero)
@ -2332,7 +2332,7 @@ again: ;
}; };
/* Try unreachable bucket */ /* Try unreachable bucket */
if ((buck = c->withdraw_bucket) && !EMPTY_LIST(buck->prefixes)) if ((buck = c->ptx->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
{ {
res = (c->afi == BGP_AF_IPV4) && !c->ext_next_hop ? res = (c->afi == BGP_AF_IPV4) && !c->ext_next_hop ?
bgp_create_ip_unreach(&s, buck, buf, end): bgp_create_ip_unreach(&s, buck, buf, end):
@ -2342,9 +2342,9 @@ again: ;
} }
/* Try reachable buckets */ /* Try reachable buckets */
if (!EMPTY_LIST(c->bucket_queue)) if (!EMPTY_LIST(c->ptx->bucket_queue))
{ {
buck = HEAD(c->bucket_queue); buck = HEAD(c->ptx->bucket_queue);
/* Cleanup empty buckets */ /* Cleanup empty buckets */
if (bgp_done_bucket(c, buck)) if (bgp_done_bucket(c, buck))