/* BGP Keepalives.
- *
- * Implemented server-style in a pthread.
- * --------------------------------------
+ * Implements a producer thread to generate BGP keepalives for peers.
* Copyright (C) 2017 Cumulus Networks, Inc.
+ * Quentin Young
*
- * This file is part of Free Range Routing.
+ * This file is part of FRRouting.
*
- * Free Range Routing is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2, or (at your option) any later
+ * FRRouting is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2, or (at your option) any later
* version.
*
- * Free Range Routing is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
+ * FRRouting is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
*
- * You should have received a copy of the GN5U General Public License along
- * with Free Range Routing; see the file COPYING. If not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
- * 02111-1307, USA.
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
+
+/* clang-format off */
#include <zebra.h>
-#include <signal.h>
-#include <sys/time.h>
+#include <pthread.h> // for pthread_mutex_lock, pthread_mutex_unlock
-#include "thread.h"
-#include "log.h"
-#include "vty.h"
-#include "monotime.h"
+#include "frr_pthread.h" // for frr_pthread
+#include "hash.h" // for hash, hash_clean, hash_create_size...
+#include "log.h" // for zlog_debug
+#include "memory.h" // for MTYPE_TMP, XFREE, XCALLOC, XMALLOC
+#include "monotime.h" // for monotime, monotime_since
-#include "bgpd/bgpd.h"
+#include "bgpd/bgpd.h" // for peer, PEER_THREAD_KEEPALIVES_ON, peer...
+#include "bgpd/bgp_debug.h" // for bgp_debug_neighbor_events
+#include "bgpd/bgp_packet.h" // for bgp_keepalive_send
#include "bgpd/bgp_keepalives.h"
-#include "bgpd/bgp_debug.h"
-#include "bgpd/bgp_attr.h"
-#include "bgpd/bgp_packet.h"
+/* clang-format on */
-/**
+/*
* Peer KeepAlive Timer.
* Associates a peer with the time of its last keepalive.
*/
struct pkat {
- // the peer to send keepalives to
+ /* the peer to send keepalives to */
struct peer *peer;
- // absolute time of last keepalive sent
+ /* absolute time of last keepalive sent */
struct timeval last;
};
/* List of peers we are sending keepalives for, and associated mutex. */
-static pthread_mutex_t peerlist_mtx = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t peerlist_cond;
-static struct list *peerlist;
-
-/* Thread control flag. */
-bool bgp_keepalives_thread_run;
+static pthread_mutex_t *peerhash_mtx;
+static pthread_cond_t *peerhash_cond;
+static struct hash *peerhash;
static struct pkat *pkat_new(struct peer *peer)
{
{
XFREE(MTYPE_TMP, pkat);
}
-/**
- * Cleanup thread resources at termination.
- *
- * @param arg not used
- */
-static void cleanup_handler(void *arg)
-{
- if (peerlist)
- list_delete(peerlist);
- peerlist = NULL;
-
- pthread_mutex_unlock(&peerlist_mtx);
- pthread_cond_destroy(&peerlist_cond);
- memset(&peerlist_cond, 0, sizeof(peerlist_cond));
-}
/*
- * Walks the list of peers, sending keepalives to those that are due for them.
+ * Callback for hash_iterate. Determines if a peer needs a keepalive and if so,
+ * generates and sends it.
*
* For any given peer, if the elapsed time since its last keepalive exceeds its
* configured keepalive timer, a keepalive is sent to the peer and its
*
* @return maximum time to wait until next update (0 if infinity)
*/
-static struct timeval update()
+static void peer_process(struct hash_backet *hb, void *arg)
{
- struct listnode *ln;
- struct pkat *pkat;
+ struct pkat *pkat = hb->data;
+
+ struct timeval *next_update = arg;
- int update_set = 0; // whether next_update has been set
- struct timeval next_update; // max sleep until next tick
static struct timeval elapsed; // elapsed time since keepalive
static struct timeval ka = {0}; // peer->v_keepalive as a timeval
static struct timeval diff; // ka - elapsed
- // see function comment
static struct timeval tolerance = {0, 100000};
- for (ALL_LIST_ELEMENTS_RO(peerlist, ln, pkat)) {
- // calculate elapsed time since last keepalive
- monotime_since(&pkat->last, &elapsed);
+ /* calculate elapsed time since last keepalive */
+ monotime_since(&pkat->last, &elapsed);
- // calculate difference between elapsed time and configured time
- ka.tv_sec = pkat->peer->v_keepalive;
- timersub(&ka, &elapsed, &diff);
+ /* calculate difference between elapsed time and configured time */
+ ka.tv_sec = pkat->peer->v_keepalive;
+ timersub(&ka, &elapsed, &diff);
- int send_keepalive = elapsed.tv_sec >= ka.tv_sec
- || timercmp(&diff, &tolerance, <);
+ int send_keepalive =
+ elapsed.tv_sec >= ka.tv_sec || timercmp(&diff, &tolerance, <);
- if (send_keepalive) {
- if (bgp_debug_neighbor_events(pkat->peer))
- zlog_debug(
- "%s [FSM] Timer (keepalive timer expire)",
- pkat->peer->host);
+ if (send_keepalive) {
+ if (bgp_debug_neighbor_events(pkat->peer))
+ zlog_debug("%s [FSM] Timer (keepalive timer expire)",
+ pkat->peer->host);
- bgp_keepalive_send(pkat->peer);
- monotime(&pkat->last);
- memset(&elapsed, 0x00, sizeof(struct timeval));
- diff = ka; // time until next keepalive == peer
- // keepalive time
- }
+ bgp_keepalive_send(pkat->peer);
+ monotime(&pkat->last);
+ memset(&elapsed, 0x00, sizeof(struct timeval));
+ diff = ka;
+ }
- // if calculated next update for this peer < current delay, use
- // it
- if (!update_set || timercmp(&diff, &next_update, <)) {
- next_update = diff;
- update_set = 1;
- }
+ /* if calculated next update for this peer < current delay, use it */
+ if (next_update->tv_sec < 0 || timercmp(&diff, next_update, <))
+ *next_update = diff;
+}
+
+static bool peer_hash_cmp(const void *f, const void *s)
+{
+ const struct pkat *p1 = f;
+ const struct pkat *p2 = s;
+
+ return p1->peer == p2->peer;
+}
+
+static unsigned int peer_hash_key(void *arg)
+{
+ struct pkat *pkat = arg;
+ return (uintptr_t)pkat->peer;
+}
+
+/* Cleanup handler / deinitializer. */
+static void bgp_keepalives_finish(void *arg)
+{
+ if (peerhash) {
+ hash_clean(peerhash, pkat_del);
+ hash_free(peerhash);
}
- return next_update;
+ peerhash = NULL;
+
+ pthread_mutex_unlock(peerhash_mtx);
+ pthread_mutex_destroy(peerhash_mtx);
+ pthread_cond_destroy(peerhash_cond);
+
+ XFREE(MTYPE_TMP, peerhash_mtx);
+ XFREE(MTYPE_TMP, peerhash_cond);
}
-void *peer_keepalives_start(void *arg)
+/*
+ * Entry function for peer keepalive generation pthread.
+ */
+void *bgp_keepalives_start(void *arg)
{
+ struct frr_pthread *fpt = arg;
+ fpt->master->owner = pthread_self();
+
struct timeval currtime = {0, 0};
+ struct timeval aftertime = {0, 0};
struct timeval next_update = {0, 0};
struct timespec next_update_ts = {0, 0};
- // initialize synchronization primitives
- pthread_mutex_lock(&peerlist_mtx);
+ peerhash_mtx = XCALLOC(MTYPE_TMP, sizeof(pthread_mutex_t));
+ peerhash_cond = XCALLOC(MTYPE_TMP, sizeof(pthread_cond_t));
- // use monotonic clock with condition variable
+ /* initialize mutex */
+ pthread_mutex_init(peerhash_mtx, NULL);
+
+ /* use monotonic clock with condition variable */
pthread_condattr_t attrs;
pthread_condattr_init(&attrs);
pthread_condattr_setclock(&attrs, CLOCK_MONOTONIC);
- pthread_cond_init(&peerlist_cond, &attrs);
+ pthread_cond_init(peerhash_cond, &attrs);
+ pthread_condattr_destroy(&attrs);
+
+ frr_pthread_set_name(fpt, NULL, "bgpd_ka");
- // initialize peerlist
- peerlist = list_new();
- peerlist->del = pkat_del;
+ /* initialize peer hashtable */
+ peerhash = hash_create_size(2048, peer_hash_key, peer_hash_cmp, NULL);
+ pthread_mutex_lock(peerhash_mtx);
- // register cleanup handlers
- pthread_cleanup_push(&cleanup_handler, NULL);
+ /* register cleanup handler */
+ pthread_cleanup_push(&bgp_keepalives_finish, NULL);
- bgp_keepalives_thread_run = true;
+ /* notify anybody waiting on us that we are done starting up */
+ frr_pthread_notify_running(fpt);
- while (bgp_keepalives_thread_run) {
- if (peerlist->count > 0)
- pthread_cond_timedwait(&peerlist_cond, &peerlist_mtx,
+ while (atomic_load_explicit(&fpt->running, memory_order_relaxed)) {
+ if (peerhash->count > 0)
+ pthread_cond_timedwait(peerhash_cond, peerhash_mtx,
&next_update_ts);
else
- while (peerlist->count == 0
- && bgp_keepalives_thread_run)
- pthread_cond_wait(&peerlist_cond,
- &peerlist_mtx);
+ while (peerhash->count == 0
+ && atomic_load_explicit(&fpt->running,
+ memory_order_relaxed))
+ pthread_cond_wait(peerhash_cond, peerhash_mtx);
monotime(&currtime);
- next_update = update();
+
+ next_update.tv_sec = -1;
+
+ hash_iterate(peerhash, peer_process, &next_update);
+ if (next_update.tv_sec == -1)
+ memset(&next_update, 0x00, sizeof(next_update));
+
+ monotime_since(&currtime, &aftertime);
+
timeradd(&currtime, &next_update, &next_update);
TIMEVAL_TO_TIMESPEC(&next_update, &next_update_ts);
}
- // clean up
+ /* clean up */
pthread_cleanup_pop(1);
return NULL;
/* --- thread external functions ------------------------------------------- */
-void peer_keepalives_on(struct peer *peer)
+void bgp_keepalives_on(struct peer *peer)
{
- pthread_mutex_lock(&peerlist_mtx);
+ if (CHECK_FLAG(peer->thread_flags, PEER_THREAD_KEEPALIVES_ON))
+ return;
+
+ struct frr_pthread *fpt = bgp_pth_ka;
+ assert(fpt->running);
+
+ /* placeholder bucket data to use for fast key lookups */
+ static struct pkat holder = {0};
+
+ /*
+ * We need to ensure that bgp_keepalives_init was called first
+ */
+ assert(peerhash_mtx);
+
+ pthread_mutex_lock(peerhash_mtx);
{
- struct listnode *ln, *nn;
- struct pkat *pkat;
-
- for (ALL_LIST_ELEMENTS(peerlist, ln, nn, pkat))
- if (pkat->peer == peer) {
- pthread_mutex_unlock(&peerlist_mtx);
- return;
- }
-
- pkat = pkat_new(peer);
- listnode_add(peerlist, pkat);
- peer_lock(peer);
+ holder.peer = peer;
+ if (!hash_lookup(peerhash, &holder)) {
+ struct pkat *pkat = pkat_new(peer);
+ hash_get(peerhash, pkat, hash_alloc_intern);
+ peer_lock(peer);
+ }
SET_FLAG(peer->thread_flags, PEER_THREAD_KEEPALIVES_ON);
}
- pthread_mutex_unlock(&peerlist_mtx);
- peer_keepalives_wake();
+ pthread_mutex_unlock(peerhash_mtx);
+ bgp_keepalives_wake();
}
-void peer_keepalives_off(struct peer *peer)
+void bgp_keepalives_off(struct peer *peer)
{
- pthread_mutex_lock(&peerlist_mtx);
- {
- struct listnode *ln, *nn;
- struct pkat *pkat;
+ if (!CHECK_FLAG(peer->thread_flags, PEER_THREAD_KEEPALIVES_ON))
+ return;
- for (ALL_LIST_ELEMENTS(peerlist, ln, nn, pkat))
- if (pkat->peer == peer) {
- XFREE(MTYPE_TMP, pkat);
- list_delete_node(peerlist, ln);
- peer_unlock(peer);
- }
+ struct frr_pthread *fpt = bgp_pth_ka;
+ assert(fpt->running);
+ /* placeholder bucket data to use for fast key lookups */
+ static struct pkat holder = {0};
+
+ /*
+ * We need to ensure that bgp_keepalives_init was called first
+ */
+ assert(peerhash_mtx);
+
+ pthread_mutex_lock(peerhash_mtx);
+ {
+ holder.peer = peer;
+ struct pkat *res = hash_release(peerhash, &holder);
+ if (res) {
+ pkat_del(res);
+ peer_unlock(peer);
+ }
UNSET_FLAG(peer->thread_flags, PEER_THREAD_KEEPALIVES_ON);
}
- pthread_mutex_unlock(&peerlist_mtx);
+ pthread_mutex_unlock(peerhash_mtx);
}
-void peer_keepalives_wake()
+void bgp_keepalives_wake()
{
- pthread_mutex_lock(&peerlist_mtx);
+ pthread_mutex_lock(peerhash_mtx);
{
- pthread_cond_signal(&peerlist_cond);
+ pthread_cond_signal(peerhash_cond);
}
- pthread_mutex_unlock(&peerlist_mtx);
+ pthread_mutex_unlock(peerhash_mtx);
+}
+
+int bgp_keepalives_stop(struct frr_pthread *fpt, void **result)
+{
+ assert(fpt->running);
+
+ atomic_store_explicit(&fpt->running, false, memory_order_relaxed);
+ bgp_keepalives_wake();
+
+ pthread_join(fpt->thread, result);
+ return 0;
}