api: better segregate client and server code

 - move memory and server specific vl_msg_api_handler_with_vm_node()
   to memory server code only
 - keep api_global_main static

Apart from being cleaner, this also helps avoiding symbols conflict
when both client and server libs are loaded in the same process, as is
done by the prom plugin.
Those symbols conflict confuse ASan and can be nasty to debug.

Type: improvement

Change-Id: Iaf58596cc753ad8d3fedd8d65c4bf480ac129c2c
Signed-off-by: Benoît Ganne <bganne@cisco.com>

1 files changed, 144 insertions, 3 deletions

diff --git a/src/vlibmemory/memory_api.c b/src/vlibmemory/memory_api.c
index 6c066a152f4..a16110f2fa1 100644
--- a/src/vlibmemory/memory_api.c
+++ b/src/vlibmemory/memory_api.c
@@ -674,6 +674,147 @@ vl_mem_api_dead_client_scan (api_main_t * am, vl_shmem_hdr_t * shm, f64 now)
     }
 }
 
+void (*vl_mem_api_fuzz_hook) (u16, void *);
+
+/* This is only to be called from a vlib/vnet app */
+static void
+vl_mem_api_handler_with_vm_node (api_main_t *am, svm_region_t *vlib_rp,
+				 void *the_msg, vlib_main_t *vm,
+				 vlib_node_runtime_t *node, u8 is_private)
+{
+  u16 id = clib_net_to_host_u16 (*((u16 *) the_msg));
+  u8 *(*handler) (void *, void *, void *);
+  u8 *(*print_fp) (void *, void *);
+  svm_region_t *old_vlib_rp;
+  void *save_shmem_hdr;
+  int is_mp_safe = 1;
+
+  if (PREDICT_FALSE (am->elog_trace_api_messages))
+    {
+      ELOG_TYPE_DECLARE (e) = {
+	.format = "api-msg: %s",
+	.format_args = "T4",
+      };
+      struct
+      {
+	u32 c;
+      } * ed;
+      ed = ELOG_DATA (am->elog_main, e);
+      if (id < vec_len (am->msg_names) && am->msg_names[id])
+	ed->c = elog_string (am->elog_main, (char *) am->msg_names[id]);
+      else
+	ed->c = elog_string (am->elog_main, "BOGUS");
+    }
+
+  if (id < vec_len (am->msg_handlers) && am->msg_handlers[id])
+    {
+      handler = (void *) am->msg_handlers[id];
+
+      if (PREDICT_FALSE (am->rx_trace && am->rx_trace->enabled))
+	vl_msg_api_trace (am, am->rx_trace, the_msg);
+
+      if (PREDICT_FALSE (am->msg_print_flag))
+	{
+	  fformat (stdout, "[%d]: %s\n", id, am->msg_names[id]);
+	  print_fp = (void *) am->msg_print_handlers[id];
+	  if (print_fp == 0)
+	    {
+	      fformat (stdout, "  [no registered print fn for msg %d]\n", id);
+	    }
+	  else
+	    {
+	      (*print_fp) (the_msg, vm);
+	    }
+	}
+      is_mp_safe = am->is_mp_safe[id];
+
+      if (!is_mp_safe)
+	{
+	  vl_msg_api_barrier_trace_context (am->msg_names[id]);
+	  vl_msg_api_barrier_sync ();
+	}
+      if (is_private)
+	{
+	  old_vlib_rp = am->vlib_rp;
+	  save_shmem_hdr = am->shmem_hdr;
+	  am->vlib_rp = vlib_rp;
+	  am->shmem_hdr = (void *) vlib_rp->user_ctx;
+	}
+
+      if (PREDICT_FALSE (vl_mem_api_fuzz_hook != 0))
+	(*vl_mem_api_fuzz_hook) (id, the_msg);
+
+      if (am->is_autoendian[id])
+	{
+	  void (*endian_fp) (void *);
+	  endian_fp = am->msg_endian_handlers[id];
+	  (*endian_fp) (the_msg);
+	}
+      if (PREDICT_FALSE (vec_len (am->perf_counter_cbs) != 0))
+	clib_call_callbacks (am->perf_counter_cbs, am, id, 0 /* before */);
+
+      (*handler) (the_msg, vm, node);
+
+      if (PREDICT_FALSE (vec_len (am->perf_counter_cbs) != 0))
+	clib_call_callbacks (am->perf_counter_cbs, am, id, 1 /* after */);
+      if (is_private)
+	{
+	  am->vlib_rp = old_vlib_rp;
+	  am->shmem_hdr = save_shmem_hdr;
+	}
+      if (!is_mp_safe)
+	vl_msg_api_barrier_release ();
+    }
+  else
+    {
+      clib_warning ("no handler for msg id %d", id);
+    }
+
+  /*
+   * Special-case, so we can e.g. bounce messages off the vnet
+   * main thread without copying them...
+   */
+  if (id >= vec_len (am->message_bounce) || !(am->message_bounce[id]))
+    {
+      if (is_private)
+	{
+	  old_vlib_rp = am->vlib_rp;
+	  save_shmem_hdr = am->shmem_hdr;
+	  am->vlib_rp = vlib_rp;
+	  am->shmem_hdr = (void *) vlib_rp->user_ctx;
+	}
+      vl_msg_api_free (the_msg);
+      if (is_private)
+	{
+	  am->vlib_rp = old_vlib_rp;
+	  am->shmem_hdr = save_shmem_hdr;
+	}
+    }
+
+  if (PREDICT_FALSE (am->elog_trace_api_messages))
+    {
+      ELOG_TYPE_DECLARE (e) = { .format = "api-msg-done(%s): %s",
+				.format_args = "t4T4",
+				.n_enum_strings = 2,
+				.enum_strings = {
+				  "barrier",
+				  "mp-safe",
+				} };
+
+      struct
+      {
+	u32 barrier;
+	u32 c;
+      } * ed;
+      ed = ELOG_DATA (am->elog_main, e);
+      if (id < vec_len (am->msg_names) && am->msg_names[id])
+	ed->c = elog_string (am->elog_main, (char *) am->msg_names[id]);
+      else
+	ed->c = elog_string (am->elog_main, "BOGUS");
+      ed->barrier = is_mp_safe;
+    }
+}
+
 static inline int
 void_mem_api_handle_msg_i (api_main_t * am, svm_region_t * vlib_rp,
 			   vlib_main_t * vm, vlib_node_runtime_t * node,
@@ -687,7 +828,7 @@ void_mem_api_handle_msg_i (api_main_t * am, svm_region_t * vlib_rp,
   if (!svm_queue_sub2 (q, (u8 *) & mp))
     {
       VL_MSG_API_UNPOISON ((void *) mp);
-      vl_msg_api_handler_with_vm_node (am, vlib_rp, (void *) mp, vm, node,
+      vl_mem_api_handler_with_vm_node (am, vlib_rp, (void *) mp, vm, node,
 				       is_private);
       return 0;
     }
@@ -737,8 +878,8 @@ vl_mem_api_handle_rpc (vlib_main_t * vm, vlib_node_runtime_t * node)
       for (i = 0; i < vec_len (vm->processing_rpc_requests); i++)
 	{
 	  mp = vm->processing_rpc_requests[i];
-	  vl_msg_api_handler_with_vm_node (am, am->vlib_rp, (void *) mp, vm,
-					   node, 0 /* is_private */ );
+	  vl_mem_api_handler_with_vm_node (am, am->vlib_rp, (void *) mp, vm,
+					   node, 0 /* is_private */);
 	}
       vl_msg_api_barrier_release ();
     }