erts: Implement tracer modules

Add the possibility to use modules as trace data receivers. The functions
in the module have to be nifs as otherwise complex trace probes will be
very hard to handle (complex means trace probes for ports for example).

This commit changes the way that the ptab->tracer field works from always
being an immediate, to now be NIL if no tracer is present or else be
the tuple {TracerModule, TracerState} where TracerModule is an atom that
is later used to lookup the appropriate tracer callbacks to call and
TracerState is just passed to the tracer callback. The default process and
port tracers have been rewritten to use the new API.

This commit also changes the order which trace messages are delivered to the
potential tracer process. Any enif_send done in a tracer module may be delayed
indefinitely because of lock order issues. If a message is delayed any other
trace message send from that process is also delayed so that order is preserved
for each traced entity. This means that for some trace events (i.e. send/receive)
the events may come in an unintuitive order (receive before send) to the
trace receiver. Timestamps are taken when the trace message is generated so
trace messages from differented processes may arrive with the timestamp
out of order.

Both the erlang:trace and seq_trace:set_system_tracer accept the new tracer
module tracers and also the backwards compatible arguments.

OTP-10267

1 files changed, 65 insertions, 45 deletions

diff --git a/erts/emulator/beam/erl_message.h b/erts/emulator/beam/erl_message.h
index ad4e65274c..608cf552a2 100644
--- a/erts/emulator/beam/erl_message.h
+++ b/erts/emulator/beam/erl_message.h
@@ -182,48 +182,64 @@ typedef struct {
     Sint len;            /* queue length */
 } ErlMessageInQueue;
 
+typedef struct erl_trace_message_queue__ {
+    struct erl_trace_message_queue__ *next; /* point to the next receiver */
+    Eterm receiver;
+    ErtsMessage* first;
+    ErtsMessage** last;  /* point to the last next pointer */
+    Sint len;            /* queue length */
+} ErlTraceMessageQueue;
+
 #endif
 
 /* Get "current" message */
 #define PEEK_MESSAGE(p)  (*(p)->msg.save)
 
+#ifdef USE_VM_PROBES
+#define LINK_MESSAGE_DTAG(mp, dt) ERL_MESSAGE_DT_UTAG(mp) = dt
+#else
+#define LINK_MESSAGE_DTAG(mp, dt)
+#endif
 
-/* Add message last in private message queue */
-#define LINK_MESSAGE_PRIVQ(p, mp) do { \
-    *(p)->msg.last = (mp); \
-    (p)->msg.last = &(mp)->next; \
-    (p)->msg.len++; \
-} while (0)
-
+#define LINK_MESSAGE_IMPL(p, first_msg, last_msg, num_msgs, where) do { \
+        *(p)->where.last = (first_msg);                                 \
+        (p)->where.last = (last_msg);                                   \
+        (p)->where.len += (num_msgs);                                   \
+    } while(0)
 
 #ifdef ERTS_SMP
 
-/* Move in message queue to end of private message queue */
-#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(P)					\
-do {									\
-    if ((P)->msg_inq.first) {						\
-	*(P)->msg.last = (P)->msg_inq.first;				\
-	(P)->msg.last = (P)->msg_inq.last;				\
-	(P)->msg.len += (P)->msg_inq.len;				\
-	(P)->msg_inq.first = NULL;					\
-	(P)->msg_inq.last = &(P)->msg_inq.first;			\
-	(P)->msg_inq.len = 0;						\
-    }									\
-} while (0)
-
-/* Add message last in message queue */
-#define LINK_MESSAGE(p, mp) do { \
-    *(p)->msg_inq.last = (mp); \
-    (p)->msg_inq.last = &(mp)->next; \
-    (p)->msg_inq.len++; \
-} while(0)
+/* Add message last in private message queue */
+#define LINK_MESSAGE_PRIVQ(p, first_msg, last_msg, len)                 \
+    do {                                                                \
+        LINK_MESSAGE_IMPL(p, first_msg, last_msg, len, msg);            \
+    } while (0)
+
+/* Add message last_msg in message queue */
+#define LINK_MESSAGE(p, first_msg, last_msg, len)       \
+    LINK_MESSAGE_IMPL(p, first_msg, last_msg, len, msg_inq)
+
+#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p)                   \
+    do {                                                \
+        if (p->msg_inq.first) {                         \
+            *p->msg.last = p->msg_inq.first;            \
+            p->msg.last = p->msg_inq.last;              \
+            p->msg.len += p->msg_inq.len;               \
+            p->msg_inq.first = NULL;                    \
+            p->msg_inq.last = &p->msg_inq.first;        \
+            p->msg_inq.len = 0;                         \
+        }                                               \
+    } while (0)
 
 #else
 
-#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(P)
+#define ERTS_SMP_MSGQ_MV_INQ2PRIVQ(p)
 
-/* Add message last in message queue */
-#define LINK_MESSAGE(p, mp) LINK_MESSAGE_PRIVQ((p), (mp))
+/* Add message last_msg in message queue */
+#define LINK_MESSAGE(p, first_msg, last_msg, len)                       \
+    do {                                                                \
+        LINK_MESSAGE_IMPL(p, first_msg, last_msg, len, msg);            \
+    } while(0)
 
 #endif
 
@@ -259,23 +275,30 @@ do {									\
 	(HEAP_FRAG_P)->off_heap.overhead = 0;				\
     } while (0)
 
+#ifdef USE_VM_PROBES
+#define ERL_MESSAGE_DT_UTAG_INIT(MP) ERL_MESSAGE_DT_UTAG(MP) = NIL
+#else
+#define ERL_MESSAGE_DT_UTAG_INIT(MP) do{ } while (0)
+#endif
+
+#define ERTS_INIT_MESSAGE(MP)                           \
+    do {                                                \
+        (MP)->next = NULL;                              \
+        ERL_MESSAGE_TERM(MP) = THE_NON_VALUE;           \
+        ERL_MESSAGE_TOKEN(MP) = NIL;                    \
+        ERL_MESSAGE_DT_UTAG_INIT(MP);                   \
+        MP->data.attached = NULL;                       \
+    } while (0)
+
 void init_message(void);
 ErlHeapFragment* new_message_buffer(Uint);
 ErlHeapFragment* erts_resize_message_buffer(ErlHeapFragment *, Uint,
 					    Eterm *, Uint);
 void free_message_buffer(ErlHeapFragment *);
 void erts_queue_dist_message(Process*, ErtsProcLocks*, ErtsDistExternal *, Eterm);
-#ifdef USE_VM_PROBES
-void erts_queue_message_probe(Process*, ErtsProcLocks*, ErtsMessage*,
-                              Eterm message, Eterm seq_trace_token, Eterm dt_utag);
-#define erts_queue_message(RP,RL,BP,Msg,SEQ) \
-    erts_queue_message_probe((RP),(RL),(BP),(Msg),(SEQ),NIL)
-#else
-void erts_queue_message(Process*, ErtsProcLocks*, ErtsMessage*,
-                        Eterm message, Eterm seq_trace_token);
-#define erts_queue_message_probe(RP,RL,BP,Msg,SEQ,TAG) \
-    erts_queue_message((RP),(RL),(BP),(Msg),(SEQ))
-#endif
+Sint erts_queue_message(Process*, ErtsProcLocks*,ErtsMessage*, Eterm);
+Sint erts_queue_messages(Process*, ErtsProcLocks*,
+                         ErtsMessage*, ErtsMessage**, Uint);
 void erts_deliver_exit_message(Eterm, Process*, ErtsProcLocks *, Eterm, Eterm);
 Sint erts_send_message(Process*, Process*, ErtsProcLocks*, Eterm, unsigned);
 void erts_link_mbuf_to_proc(Process *proc, ErlHeapFragment *bp);
@@ -354,9 +377,7 @@ ERTS_GLB_FORCE_INLINE ErtsMessage *erts_alloc_message(Uint sz, Eterm **hpp)
 
     if (sz == 0) {
 	mp = erts_alloc_message_ref();
-	mp->next = NULL;
-	ERL_MESSAGE_TERM(mp) = NIL;
-	mp->data.attached = NULL;
+        ERTS_INIT_MESSAGE(mp);
 	if (hpp)
 	    *hpp = NULL;
 	return mp;
@@ -365,8 +386,7 @@ ERTS_GLB_FORCE_INLINE ErtsMessage *erts_alloc_message(Uint sz, Eterm **hpp)
     mp = erts_alloc(ERTS_ALC_T_MSG,
 		    sizeof(ErtsMessage) + (sz - 1)*sizeof(Eterm));
 
-    mp->next = NULL;
-    ERL_MESSAGE_TERM(mp) = NIL;
+    ERTS_INIT_MESSAGE(mp);
     mp->data.attached = ERTS_MSG_COMBINED_HFRAG;
     ERTS_INIT_HEAP_FRAG(&mp->hfrag, sz, sz);