erts: Fix PAM to be callable from non-scheduler thread

also simplified the interface to to run PAM from trace

3 files changed, 88 insertions, 68 deletions

diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 7d64529250..051c107d1f 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -414,19 +414,27 @@ get_match_pseudo_process(Process *c_p, Uint heap_size)
 {
     ErtsMatchPseudoProcess *mpsp;
 #ifdef ERTS_SMP
-    ErtsSchedulerData *esdp = c_p ? c_p->scheduler_data : erts_get_scheduler_data();
+    ErtsSchedulerData *esdp;
+
+    esdp = c_p ? c_p->scheduler_data : erts_get_scheduler_data();
+
+    mpsp = esdp ? esdp->match_pseudo_process :
+        (ErtsMatchPseudoProcess*) erts_smp_tsd_get(match_pseudo_process_key);
 
-    mpsp = (ErtsMatchPseudoProcess *) esdp->match_pseudo_process;
-    if (mpsp)
+    if (mpsp) {
+        ASSERT(mpsp == erts_smp_tsd_get(match_pseudo_process_key));
+        ASSERT(mpsp->process.scheduler_data == esdp);
 	cleanup_match_pseudo_process(mpsp, 0);
+    }
     else {
 	ASSERT(erts_smp_tsd_get(match_pseudo_process_key) == NULL);
 	mpsp = create_match_pseudo_process();
-	esdp->match_pseudo_process = (void *) mpsp;
+        if (esdp) {
+            esdp->match_pseudo_process = (void *) mpsp;
+        }
+        mpsp->process.scheduler_data = esdp;
 	erts_smp_tsd_set(match_pseudo_process_key, (void *) mpsp);
     }
-    ASSERT(mpsp == erts_smp_tsd_get(match_pseudo_process_key));
-    mpsp->process.scheduler_data = esdp;
 #else
     mpsp = match_pseudo_process;
     cleanup_match_pseudo_process(mpsp, 0);
@@ -1206,32 +1214,37 @@ done:
     return ret;
 }
     
-Eterm erts_match_set_run(Process *c_p,
-                         Process *self,
-                         Binary *mpsp,
-			 Eterm *args, int num_args,
-			 enum erts_pam_run_flags in_flags,
-			 Uint32 *return_flags) 
+/* Returns
+ *   am_false      if no match or
+ *                 if {message,false} has been called,
+ *   am_true       if {message,_} has NOT been called or
+ *                 if {message,true} has been called,
+ *   Msg           if {message,Msg} has been called.
+ *
+ *   If return value is_not_immed
+ *   then erts_match_set_release_result_trace() must be called to release it.
+ */
+Eterm erts_match_set_run_trace(Process *c_p,
+                               Process *self,
+                               Binary *mpsp,
+                               Eterm *args, int num_args,
+                               enum erts_pam_run_flags in_flags,
+                               Uint32 *return_flags)
 {
     Eterm ret;
 
     ret = db_prog_match(c_p, self, mpsp, NIL, args, num_args,
 			in_flags, return_flags);
-#if defined(HARDDEBUG)
-    if (is_non_value(ret)) {
-	erts_fprintf(stderr, "Failed\n");
-    } else {
-	erts_fprintf(stderr, "Returning : %T\n", ret);
+
+    ASSERT(!(is_non_value(ret) && *return_flags));
+
+    if (is_non_value(ret) || ret == am_false) {
+        erts_match_set_release_result(c_p);
+        return am_false;
     }
-#endif
+    if (is_immed(ret))
+        erts_match_set_release_result(c_p);
     return ret;
-    /* Returns 
-     *   THE_NON_VALUE if no match
-     *   am_false      if {message,false} has been called,
-     *   am_true       if {message,_} has not been called or
-     *                 if {message,true} has been called,
-     *   Msg           if {message,Msg} has been called.
-     */
 }
 
 static Eterm erts_match_set_run_ets(Process *p, Binary *mpsp,
@@ -1774,6 +1787,7 @@ Eterm db_prog_match(Process *c_p,
 #endif /* DMC_DEBUG */
 
     ERTS_UNDEF(n,0);
+    ERTS_UNDEF(current_scheduled,NULL);
 
     ASSERT(c_p || !(in_flags & ERTS_PAM_COPY_RESULT));
 
@@ -1784,8 +1798,8 @@ Eterm db_prog_match(Process *c_p,
        because of floating point exceptions. Do *after* mpsp is set!!! */
 
     esdp = ERTS_GET_SCHEDULER_DATA_FROM_PROC(psp);
-    ASSERT(esdp != NULL);
-    current_scheduled = esdp->current_process;
+    if (esdp)
+        current_scheduled = esdp->current_process;
     /* SMP: psp->scheduler_data is set by get_match_pseudo_process */
 
 #ifdef DMC_DEBUG
@@ -2517,7 +2531,8 @@ success:
     }
 #endif
 
-    esdp->current_process = current_scheduled;
+    if (esdp)
+        esdp->current_process = current_scheduled;
 
     return ret;
 #undef FAIL
@@ -5073,7 +5088,7 @@ static Eterm match_spec_test(Process *p, Eterm against, Eterm spec, int trace)
 	    }
 	    save_cp = p->cp;
 	    p->cp = NULL;
-	    res = erts_match_set_run(p, p,
+	    res = erts_match_set_run_trace(p, p,
                       mps, arr, n,
 		      ERTS_PAM_COPY_RESULT|ERTS_PAM_IGNORE_TRACE_SILENT,
 		      &ret_flags);
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index be0d2f0939..9f3341537d 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -825,13 +825,13 @@ trace_send(Process *p, Eterm to, Eterm msg)
 	Uint32 return_flags;
 	args[0] = to;
 	args[1] = msg;
-	pam_result = erts_match_set_run(p, p,
-                                        te->match_spec, args, 2,
-					ERTS_PAM_TMP_RESULT, &return_flags);
-	if (is_non_value(pam_result)
-	    || pam_result == am_false
-	    || (ERTS_TRACE_FLAGS(p) & F_TRACE_SILENT)) {
-            erts_match_set_release_result(p);
+	pam_result = erts_match_set_run_trace(p, p,
+                                              te->match_spec, args, 2,
+                                              ERTS_PAM_TMP_RESULT, &return_flags);
+	if (pam_result == am_false)
+            return;
+        if (ERTS_TRACE_FLAGS(p) & F_TRACE_SILENT) {
+            erts_match_set_release_result_trace(p, pam_result);
 	    return;
 	}
     } else
@@ -850,9 +850,9 @@ trace_send(Process *p, Eterm to, Eterm msg)
     if (is_tracer_enabled(p, ERTS_PROC_LOCK_MAIN, &p->common, &tnif,
                           TRACE_FUN_E_SEND, operation)) {
         send_to_tracer_nif(p, &p->common, p->common.id, tnif, TRACE_FUN_T_SEND,
-                operation, msg, to, pam_result);
+                           operation, msg, to, pam_result);
     }
-    erts_match_set_release_result(p);
+    erts_match_set_release_result_trace(p, pam_result);
 }
 
 /* Send {trace_ts, Pid, receive, Msg, Timestamp}
@@ -886,13 +886,13 @@ trace_receive(Process* receiver,
             args[1] = am_undefined;
         }
         args[2] = msg;
-        pam_result = erts_match_set_run(NULL, receiver,
-                                        te->match_spec, args, 3,
-                                        ERTS_PAM_TMP_RESULT, &return_flags);
-        if (is_non_value(pam_result)
-            || pam_result == am_false
-            || (ERTS_TRACE_FLAGS(receiver) & F_TRACE_SILENT)) {
-            erts_match_set_release_result(NULL);
+        pam_result = erts_match_set_run_trace(NULL, receiver,
+                                              te->match_spec, args, 3,
+                                              ERTS_PAM_TMP_RESULT, &return_flags);
+        if (pam_result == am_false)
+            return;
+        if (ERTS_TRACE_FLAGS(receiver) & F_TRACE_SILENT) {
+            erts_match_set_release_result_trace(NULL, pam_result);
             return;
         }
     } else
@@ -904,7 +904,7 @@ trace_receive(Process* receiver,
                            tnif, TRACE_FUN_T_RECEIVE,
                            am_receive, msg, THE_NON_VALUE, pam_result);
     }
-    erts_match_set_release_result(NULL);
+    erts_match_set_release_result_trace(NULL, pam_result);
 }
 
 int
@@ -1264,21 +1264,14 @@ erts_call_trace(Process* p, BeamInstr mfa[3], Binary *match_spec,
            may remove it, and we still want to generate a trace message */
         erts_tracer_update(&pre_ms_tracer, *tracer);
         tracer = &pre_ms_tracer;
-        pam_result = erts_match_set_run(p, p,
-                                        match_spec, args, arity,
-                                        ERTS_PAM_TMP_RESULT, &return_flags);
-        if (is_non_value(pam_result)) {
-            erts_match_set_release_result(p);
-            UnUseTmpHeap(ERL_SUB_BIN_SIZE,p);
-            ERTS_TRACER_CLEAR(&pre_ms_tracer);
-            return 0;
-        }
+        pam_result = erts_match_set_run_trace(p, p,
+                                              match_spec, args, arity,
+                                              ERTS_PAM_TMP_RESULT, &return_flags);
     }
 
     if (tracee_flags == &meta_flags) {
         /* Meta trace */
         if (pam_result == am_false) {
-            erts_match_set_release_result(p);
             UnUseTmpHeap(ERL_SUB_BIN_SIZE,p);
             ERTS_TRACER_CLEAR(&pre_ms_tracer);
             return return_flags;
@@ -1286,13 +1279,12 @@ erts_call_trace(Process* p, BeamInstr mfa[3], Binary *match_spec,
     } else {
         /* Non-meta trace */
         if (*tracee_flags & F_TRACE_SILENT) {
-            erts_match_set_release_result(p);
+            erts_match_set_release_result_trace(p, pam_result);
             UnUseTmpHeap(ERL_SUB_BIN_SIZE,p);
             ERTS_TRACER_CLEAR(&pre_ms_tracer);
             return 0;
         }
         if (pam_result == am_false) {
-            erts_match_set_release_result(p);
             UnUseTmpHeap(ERL_SUB_BIN_SIZE,p);
             ERTS_TRACER_CLEAR(&pre_ms_tracer);
             return return_flags;
@@ -1328,11 +1320,14 @@ erts_call_trace(Process* p, BeamInstr mfa[3], Binary *match_spec,
      * Build the trace tuple and send it to the port.
      */
     send_to_tracer_nif_raw(p, NULL, *tracer, *tracee_flags, p->common.id,
-                           tnif, TRACE_FUN_T_CALL, am_call, mfa_tuple, THE_NON_VALUE, pam_result);
-    erts_match_set_release_result(p);
+                           tnif, TRACE_FUN_T_CALL, am_call, mfa_tuple,
+                           THE_NON_VALUE, pam_result);
 
-    if (match_spec && tracer == &pre_ms_tracer)
-        ERTS_TRACER_CLEAR(&pre_ms_tracer);
+    if (match_spec) {
+        erts_match_set_release_result_trace(p, pam_result);
+        if (tracer == &pre_ms_tracer)
+            ERTS_TRACER_CLEAR(&pre_ms_tracer);
+    }
 
     return return_flags;
 }
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 328bfe344c..baa0a201d1 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -1486,6 +1486,16 @@ do {								\
 extern Binary *erts_match_set_compile(Process *p, Eterm matchexpr, Eterm MFA);
 Eterm erts_match_set_lint(Process *p, Eterm matchexpr); 
 extern void erts_match_set_release_result(Process* p);
+ERTS_GLB_INLINE void erts_match_set_release_result_trace(Process* p, Eterm);
+
+#if ERTS_GLB_INLINE_INCL_FUNC_DEF
+ERTS_GLB_INLINE
+void erts_match_set_release_result_trace(Process* p, Eterm pam_result)
+{
+    if (is_not_immed(pam_result))
+        erts_match_set_release_result(p);
+}
+#endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
 enum erts_pam_run_flags {
     ERTS_PAM_TMP_RESULT=1,
@@ -1493,12 +1503,12 @@ enum erts_pam_run_flags {
     ERTS_PAM_CONTIGUOUS_TUPLE=4,
     ERTS_PAM_IGNORE_TRACE_SILENT=8
 };
-extern Eterm erts_match_set_run(Process *p,
-                                Process *self,
-                                Binary *mpsp,
-				Eterm *args, int num_args,
-				enum erts_pam_run_flags in_flags,
-				Uint32 *return_flags);
+extern Eterm erts_match_set_run_trace(Process *p,
+                                      Process *self,
+                                      Binary *mpsp,
+                                      Eterm *args, int num_args,
+                                      enum erts_pam_run_flags in_flags,
+                                      Uint32 *return_flags);
 extern Eterm erts_match_set_get_source(Binary *mpsp);
 extern void erts_match_prog_foreach_offheap(Binary *b,
 					    void (*)(ErlOffHeap *, void *),