isisd: add a slight delay to lsp_regenerate_schedule
isisd implements a holdoff interval and will refrain from regenerating
an lsp if the difference between the current time and its last refresh
is less than the holdoff interval. Instead, it will schedule a timer
to regenerate the lsp after the holdoff interval has passed.
This implementation has one disadvantage in the case where there is a
succession of calls to lsp_regenerate_schedule. In such a case, the
first call will trigger an immediate regeneration of the lsp, while the
other calls will only schedule the regeneration timer. This leads to
cases where it takes holdoff interval time for information to propagate,
just because the information was only available e.g. at the second call
of lsp_regenerate_schedule in such a succession of calls.
By not immediately regenerating an lsp if the last generation time
is sufficiently long ago, but instead scheduling the regeneration with a
very small delay, we allow all information from such a succession of
calls to be considered.
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Acked-by: Donald Sharp <sharpd@cumulusnetworks.com>
diff --git a/isisd/isis_lsp.c b/isisd/isis_lsp.c
index 74a86c8..9ac0221 100644
--- a/isisd/isis_lsp.c
+++ b/isisd/isis_lsp.c
@@ -1681,10 +1681,13 @@
lsp_build (newlsp, area);
/* time to calculate our checksum */
lsp_seqnum_update (newlsp);
+ newlsp->last_generated = time(NULL);
lsp_set_all_srmflags (newlsp);
refresh_time = lsp_refresh_time (newlsp, rem_lifetime);
+
THREAD_TIMER_OFF (area->t_lsp_refresh[level - 1]);
+ area->lsp_regenerate_pending[level - 1] = 0;
if (level == IS_LEVEL_1)
THREAD_TIMER_ON (master, area->t_lsp_refresh[level - 1],
lsp_l1_refresh, area, refresh_time);
@@ -1704,6 +1707,8 @@
ntohs (newlsp->lsp_header->rem_lifetime),
refresh_time);
}
+ sched_debug("ISIS (%s): Built L%d LSP. Set triggered regenerate to non-pending.",
+ area->area_tag, level);
return ISIS_OK;
}
@@ -1766,6 +1771,7 @@
else if (level == IS_LEVEL_2)
THREAD_TIMER_ON (master, area->t_lsp_refresh[level - 1],
lsp_l2_refresh, area, refresh_time);
+ area->lsp_regenerate_pending[level - 1] = 0;
if (isis->debugs & DEBUG_UPDATE_PACKETS)
{
@@ -1779,6 +1785,8 @@
ntohs (lsp->lsp_header->rem_lifetime),
refresh_time);
}
+ sched_debug("ISIS (%s): Rebuilt L%d LSP. Set triggered regenerate to non-pending.",
+ area->area_tag, level);
return ISIS_OK;
}
@@ -1800,6 +1808,7 @@
if ((area->is_type & IS_LEVEL_1) == 0)
return ISIS_ERROR;
+ sched_debug("ISIS (%s): LSP L1 refresh timer expired. Refreshing LSP...", area->area_tag);
return lsp_regenerate (area, IS_LEVEL_1);
}
@@ -1817,6 +1826,7 @@
if ((area->is_type & IS_LEVEL_2) == 0)
return ISIS_ERROR;
+ sched_debug("ISIS (%s): LSP L2 refresh timer expired. Refreshing LSP...", area->area_tag);
return lsp_regenerate (area, IS_LEVEL_2);
}
@@ -1826,6 +1836,7 @@
struct isis_lsp *lsp;
u_char id[ISIS_SYS_ID_LEN + 2];
time_t now, diff;
+ long timeout;
struct listnode *cnode;
struct isis_circuit *circuit;
int lvl;
@@ -1833,6 +1844,9 @@
if (area == NULL)
return ISIS_ERROR;
+ sched_debug("ISIS (%s): Scheduling regeneration of %s LSPs, %sincluding PSNs",
+ area->area_tag, circuit_t2string(level), all_pseudo ? "" : "not ");
+
memcpy (id, isis->sysid, ISIS_SYS_ID_LEN);
LSP_PSEUDO_ID (id) = LSP_FRAGMENT (id) = 0;
now = time (NULL);
@@ -1842,29 +1856,38 @@
if (!((level & lvl) && (area->is_type & lvl)))
continue;
+ sched_debug("ISIS (%s): Checking whether L%d needs to be scheduled",
+ area->area_tag, lvl);
+
if (area->lsp_regenerate_pending[lvl - 1])
- continue;
+ {
+ struct timeval remain = thread_timer_remain(area->t_lsp_refresh[lvl - 1]);
+ sched_debug("ISIS (%s): Regeneration is already pending, nothing todo."
+ " (Due in %lld.%03lld seconds)", area->area_tag,
+ (long long)remain.tv_sec, (long long)remain.tv_usec / 1000);
+ continue;
+ }
lsp = lsp_search (id, area->lspdb[lvl - 1]);
if (!lsp)
- continue;
+ {
+ sched_debug("ISIS (%s): We do not have any LSPs to regenerate, nothing todo.",
+ area->area_tag);
+ continue;
+ }
/*
* Throttle avoidance
*/
+ sched_debug("ISIS (%s): Will schedule regen timer. Last run was: %lld, Now is: %lld",
+ area->area_tag, (long long)lsp->last_generated, (long long)now);
THREAD_TIMER_OFF (area->t_lsp_refresh[lvl - 1]);
diff = now - lsp->last_generated;
if (diff < area->lsp_gen_interval[lvl - 1])
{
- area->lsp_regenerate_pending[lvl - 1] = 1;
- if (lvl == IS_LEVEL_1)
- THREAD_TIMER_ON (master, area->t_lsp_refresh[lvl - 1],
- lsp_l1_refresh, area,
- area->lsp_gen_interval[lvl - 1] - diff);
- else if (lvl == IS_LEVEL_2)
- THREAD_TIMER_ON (master, area->t_lsp_refresh[lvl - 1],
- lsp_l2_refresh, area,
- area->lsp_gen_interval[lvl - 1] - diff);
+ timeout = 1000 * (area->lsp_gen_interval[lvl - 1] - diff);
+ sched_debug("ISIS (%s): Scheduling in %ld ms to match configured lsp_gen_interval",
+ area->area_tag, timeout);
}
else
{
@@ -1873,13 +1896,21 @@
* directly. However if the lsp_regenerate call is queued for
* later execution it works.
*/
- area->lsp_regenerate_pending[lvl - 1] = 1;
- if (lvl == IS_LEVEL_1)
- THREAD_TIMER_ON (master, area->t_lsp_refresh[lvl - 1],
- lsp_l1_refresh, area, 0);
- else if (lvl == IS_LEVEL_2)
- THREAD_TIMER_ON (master, area->t_lsp_refresh[lvl - 1],
- lsp_l2_refresh, area, 0);
+ timeout = 100;
+ sched_debug("ISIS (%s): Last generation was more than lsp_gen_interval ago."
+ " Scheduling for execution in %ld ms.", area->area_tag, timeout);
+ }
+
+ area->lsp_regenerate_pending[lvl - 1] = 1;
+ if (lvl == IS_LEVEL_1)
+ {
+ THREAD_TIMER_MSEC_ON(master, area->t_lsp_refresh[lvl - 1],
+ lsp_l1_refresh, area, timeout);
+ }
+ else if (lvl == IS_LEVEL_2)
+ {
+ THREAD_TIMER_MSEC_ON(master, area->t_lsp_refresh[lvl - 1],
+ lsp_l2_refresh, area, timeout);
}
}
@@ -2231,13 +2262,18 @@
struct isis_lsp *lsp;
u_char lsp_id[ISIS_SYS_ID_LEN + 2];
time_t now, diff;
+ long timeout;
int lvl;
+ struct isis_area *area = circuit->area;
if (circuit == NULL ||
circuit->circ_type != CIRCUIT_T_BROADCAST ||
circuit->state != C_STATE_UP)
return ISIS_OK;
+ sched_debug("ISIS (%s): Scheduling regeneration of %s pseudo LSP for interface %s",
+ area->area_tag, circuit_t2string(level), circuit->interface->name);
+
memcpy (lsp_id, isis->sysid, ISIS_SYS_ID_LEN);
LSP_PSEUDO_ID (lsp_id) = circuit->circuit_id;
LSP_FRAGMENT (lsp_id) = 0;
@@ -2245,39 +2281,74 @@
for (lvl = IS_LEVEL_1; lvl <= IS_LEVEL_2; lvl++)
{
- if (!((level & lvl) && (circuit->is_type & lvl)))
- continue;
+ sched_debug("ISIS (%s): Checking whether L%d pseudo LSP needs to be scheduled",
+ area->area_tag, lvl);
- if (circuit->u.bc.is_dr[lvl - 1] == 0 ||
- circuit->lsp_regenerate_pending[lvl - 1])
- continue;
+ if (!((level & lvl) && (circuit->is_type & lvl)))
+ {
+ sched_debug("ISIS (%s): Level is not active on circuit",
+ area->area_tag);
+ continue;
+ }
+
+ if (circuit->u.bc.is_dr[lvl - 1] == 0)
+ {
+ sched_debug("ISIS (%s): This IS is not DR, nothing to do.",
+ area->area_tag);
+ continue;
+ }
+
+ if (circuit->lsp_regenerate_pending[lvl - 1])
+ {
+ struct timeval remain =
+ thread_timer_remain(circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1]);
+ sched_debug("ISIS (%s): Regenerate is already pending, nothing todo."
+ " (Due in %lld.%03lld seconds)", area->area_tag,
+ (long long)remain.tv_sec, (long long)remain.tv_usec/1000);
+ continue;
+ }
lsp = lsp_search (lsp_id, circuit->area->lspdb[lvl - 1]);
if (!lsp)
- continue;
+ {
+ sched_debug("ISIS (%s): Pseudonode LSP does not exist yet, nothing to regenerate.",
+ area->area_tag);
+ continue;
+ }
/*
* Throttle avoidance
*/
+ sched_debug("ISIS (%s): Will schedule PSN regen timer. Last run was: %lld, Now is: %lld",
+ area->area_tag, (long long)lsp->last_generated, (long long) now);
THREAD_TIMER_OFF (circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1]);
diff = now - lsp->last_generated;
if (diff < circuit->area->lsp_gen_interval[lvl - 1])
{
- circuit->lsp_regenerate_pending[lvl - 1] = 1;
- if (lvl == IS_LEVEL_1)
- THREAD_TIMER_ON (master,
- circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1],
- lsp_l1_refresh_pseudo, circuit,
- circuit->area->lsp_gen_interval[lvl - 1] - diff);
- else if (lvl == IS_LEVEL_2)
- THREAD_TIMER_ON (master,
- circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1],
- lsp_l2_refresh_pseudo, circuit,
- circuit->area->lsp_gen_interval[lvl - 1] - diff);
+ timeout = 1000 * (circuit->area->lsp_gen_interval[lvl - 1] - diff);
+ sched_debug("ISIS (%s): Sechduling in %ld ms to match configured lsp_gen_interval",
+ area->area_tag, timeout);
}
else
{
- lsp_regenerate_pseudo (circuit, lvl);
+ timeout = 100;
+ sched_debug("ISIS (%s): Last generation was more than lsp_gen_interval ago."
+ " Scheduling for execution in %ld ms.", area->area_tag, timeout);
+ }
+
+ circuit->lsp_regenerate_pending[lvl - 1] = 1;
+
+ if (lvl == IS_LEVEL_1)
+ {
+ THREAD_TIMER_MSEC_ON(master,
+ circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1],
+ lsp_l1_refresh_pseudo, circuit, timeout);
+ }
+ else if (lvl == IS_LEVEL_2)
+ {
+ THREAD_TIMER_MSEC_ON(master,
+ circuit->u.bc.t_refresh_pseudo_lsp[lvl - 1],
+ lsp_l2_refresh_pseudo, circuit, timeout);
}
}