init / exit function ordering
The vlib init function subsystem now supports a mix of procedural and
formally-specified ordering constraints. We should eliminate procedural
knowledge wherever possible.
The following schemes are *roughly* equivalent:
static clib_error_t *init_runs_first (vlib_main_t *vm)
{
clib_error_t *error;
... do some stuff...
if ((error = vlib_call_init_function (init_runs_next)))
return error;
...
}
VLIB_INIT_FUNCTION (init_runs_first);
and
static clib_error_t *init_runs_first (vlib_main_t *vm)
{
... do some stuff...
}
VLIB_INIT_FUNCTION (init_runs_first) =
{
.runs_before = VLIB_INITS("init_runs_next"),
};
The first form will [most likely] call "init_runs_next" on the
spot. The second form means that "init_runs_first" runs before
"init_runs_next," possibly much earlier in the sequence.
Please DO NOT construct sets of init functions where A before B
actually means A *right before* B. It's not necessary - simply combine
A and B - and it leads to hugely annoying debugging exercises when
trying to switch from ad-hoc procedural ordering constraints to formal
ordering constraints.
Change-Id: I5e4353503bf43b4acb11a45fb33c79a5ade8426c
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/src/vnet/dpo/dpo.c b/src/vnet/dpo/dpo.c
index df78456..13ae37a 100644
--- a/src/vnet/dpo/dpo.c
+++ b/src/vnet/dpo/dpo.c
@@ -16,7 +16,7 @@
* @brief
* A Data-Path Object is an object that represents actions that are
* applied to packets are they are switched through VPP.
- *
+ *
* The DPO is a base class that is specialised by other objects to provide
* concrete actions
*
@@ -267,10 +267,10 @@
* the destination is written in a single u64 write - hence atomically w.r.t
* any packets inflight.
*/
- *((u64*)dst) = *(u64*)src;
+ *((u64*)dst) = *(u64*)src;
dpo_lock(dst);
- dpo_unlock(&tmp);
+ dpo_unlock(&tmp);
}
int
@@ -592,7 +592,12 @@
return (NULL);
}
-VLIB_INIT_FUNCTION(dpo_module_init);
+/* *INDENT-OFF* */
+VLIB_INIT_FUNCTION(dpo_module_init) =
+{
+ .runs_before = VLIB_INITS ("ip_main_init"),
+};
+/* *INDENT-ON* */
static clib_error_t *
dpo_memory_show (vlib_main_t * vm,