gbproxy: Add new VTY-managed timer: link-list clean-stale-timer
This timer allows periodically cleaning up stale links in link-list of
each gbproxy_peer. Previous to this patch, this kind of cleanup
(gbproxy_remove_stale_link_infos) was being done only as a consequence
of external events being triggered, such as a message from that peer
being received.
It was found in a production network agreggating several BSS that some
of them were offline for a longtime but gbproxy was still caching big
amounts of really old link_info for the NSEI assigned to those BSS,
because since they were probably turned off abruptely, no new messages
were received from it which would trigger the cleanup.
As a consequence, it has been observed that a timer to periodically
clean up old entries (link-list max-age) is requird in case w don't
receive messages from that NSEI periodically.
Related: SYS#4431
Change-Id: Ic777016f6d4f0e30fb736484774ca46878f17b7a
diff --git a/src/gprs/gb_proxy_vty.c b/src/gprs/gb_proxy_vty.c
index d743355..52c39fd 100644
--- a/src/gprs/gb_proxy_vty.c
+++ b/src/gprs/gb_proxy_vty.c
@@ -120,6 +120,9 @@
vty_out(vty, " secondary-sgsn nsei %u%s", g_cfg->nsip_sgsn2_nsei,
VTY_NEWLINE);
+ if (g_cfg->clean_stale_timer_freq > 0)
+ vty_out(vty, " link-list clean-stale-timer %u%s",
+ g_cfg->clean_stale_timer_freq, VTY_NEWLINE);
if (g_cfg->tlli_max_age > 0)
vty_out(vty, " link-list max-age %d%s",
g_cfg->tlli_max_age, VTY_NEWLINE);
@@ -407,6 +410,44 @@
#define GBPROXY_LINK_LIST_STR "Set TLLI list parameters\n"
#define GBPROXY_LINK_STR "Set TLLI parameters\n"
+
+#define GBPROXY_CLEAN_STALE_TIMER_STR "Periodic timer to clean stale links\n"
+
+DEFUN(cfg_gbproxy_link_list_clean_stale_timer,
+ cfg_gbproxy_link_list_clean_stale_timer_cmd,
+ "link-list clean-stale-timer <1-999999>",
+ GBPROXY_LINK_LIST_STR GBPROXY_CLEAN_STALE_TIMER_STR
+ "Frequency at which the periodic timer is fired (in seconds)\n")
+{
+ struct gbproxy_peer *peer;
+ g_cfg->clean_stale_timer_freq = (unsigned int) atoi(argv[0]);
+
+ /* Re-schedule running timers soon in case prev frequency was really big
+ and new frequency is desired to be lower. After initial run, periodic
+ time is used. Use random() to avoid firing timers for all peers at
+ the same time */
+ llist_for_each_entry(peer, &g_cfg->bts_peers, list)
+ osmo_timer_schedule(&peer->clean_stale_timer,
+ random() % 5, random() % 1000000);
+
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_gbproxy_link_list_no_clean_stale_timer,
+ cfg_gbproxy_link_list_no_clean_stale_timer_cmd,
+ "no link-list clean-stale-timer",
+ NO_STR GBPROXY_LINK_LIST_STR GBPROXY_CLEAN_STALE_TIMER_STR)
+
+{
+ struct gbproxy_peer *peer;
+ g_cfg->clean_stale_timer_freq = 0;
+
+ llist_for_each_entry(peer, &g_cfg->bts_peers, list)
+ osmo_timer_del(&peer->clean_stale_timer);
+
+ return CMD_SUCCESS;
+}
+
#define GBPROXY_MAX_AGE_STR "Limit maximum age\n"
DEFUN(cfg_gbproxy_link_list_max_age,
@@ -846,6 +887,7 @@
install_element(GBPROXY_NODE, &cfg_gbproxy_secondary_sgsn_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_patch_ptmsi_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_acquire_imsi_cmd);
+ install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_clean_stale_timer_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_max_age_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_max_len_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_keep_mode_cmd);
@@ -857,6 +899,7 @@
install_element(GBPROXY_NODE, &cfg_gbproxy_no_secondary_sgsn_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_no_patch_ptmsi_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_no_acquire_imsi_cmd);
+ install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_no_clean_stale_timer_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_no_max_age_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_list_no_max_len_cmd);
install_element(GBPROXY_NODE, &cfg_gbproxy_link_no_stored_msgs_max_len_cmd);