Merge branch 'rickard/process-status/OTP-9197' into maint-r14

* rickard/process-status/OTP-9197:
  Fix thread unsafe access
  Fix lost wakeup when process garbage collected by other
  Only set status P_WAITING when needed
  Add testcase for process_info() badarg bug

4 files changed, 80 insertions, 11 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index 7b2aac0908..47bff4a427 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -3419,7 +3419,8 @@ void process_main(void)
 		r(0) = c_p->def_arg_reg[0];
 		x(1) = c_p->def_arg_reg[1];
 		x(2) = c_p->def_arg_reg[2];
-		if (c_p->status == P_WAITING) {
+		if (c_p->flags & F_HIBERNATE_SCHED) {
+		    c_p->flags &= ~F_HIBERNATE_SCHED;
 		    goto do_schedule;
 		}
 		Dispatch();
@@ -5224,6 +5225,7 @@ void process_main(void)
  OpCase(i_hibernate): {
      SWAPOUT;
      if (erts_hibernate(c_p, r(0), x(1), x(2), reg)) {
+	 c_p->flags &= ~F_HIBERNATE_SCHED;
 	 goto do_schedule;
      } else {
 	 I = handle_error(c_p, I, reg, hibernate_3);
@@ -6276,15 +6278,17 @@ erts_hibernate(Process* c_p, Eterm module, Eterm function, Eterm args, Eterm* re
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	c_p->status = P_WAITING;
 #ifdef ERTS_SMP
 	ERTS_SMP_MSGQ_MV_INQ2PRIVQ(c_p);
 	if (c_p->msg.len > 0)
 	    erts_add_to_runq(c_p);
+	else
 #endif
+	    c_p->status = P_WAITING;
     }
     erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MSGQ|ERTS_PROC_LOCK_STATUS);
     c_p->current = bif_export[BIF_hibernate_3]->code;
+    c_p->flags |= F_HIBERNATE_SCHED; /* Needed also when woken! */
     return 1;
 }
 
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index 428ca12eb1..21625921d5 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -2857,7 +2857,6 @@ resume_process(Process *p)
 	return;
     switch(p->rstatus) {
     case P_RUNABLE:
-	*statusp = P_WAITING;  /* make erts_add_to_runq work */
 	erts_add_to_runq(p);
 	break;
     case P_WAITING:
@@ -4653,7 +4652,7 @@ internal_add_to_runq(ErtsRunQueue *runq, Process *p)
     if (p->status_flags & ERTS_PROC_SFLG_INRUNQ)
 	return NULL;
     else if (p->runq_flags & ERTS_PROC_RUNQ_FLG_RUNNING) {
-	ASSERT(p->status != P_SUSPENDED);
+	ASSERT(p->rcount == 0);
 	ERTS_DBG_CHK_PROCS_RUNQ_NOPROC(runq, p);
 	p->status_flags |= ERTS_PROC_SFLG_PENDADD2SCHEDQ;
 	return NULL;
@@ -4664,9 +4663,8 @@ internal_add_to_runq(ErtsRunQueue *runq, Process *p)
     ERTS_DBG_CHK_PROCS_RUNQ_NOPROC(runq, p);
 #ifndef ERTS_SMP
     /* Never schedule a suspended process (ok in smp case) */
-    ASSERT(p->status != P_SUSPENDED);
+    ASSERT(p->rcount == 0);
     add_runq = runq;
-
 #else
     ASSERT(!p->bound_runq || p->bound_runq == p->run_queue);
     if (p->bound_runq) {
@@ -5166,7 +5164,7 @@ Process *schedule(Process *p, int calls)
 	    handle_pending_suspend(p,
 				   ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_STATUS);
 	    ASSERT(!(p->status_flags & ERTS_PROC_SFLG_PENDADD2SCHEDQ)
-		   || p->status != P_SUSPENDED);
+		   || p->rcount == 0);
 	}
 #endif
 	erts_smp_runq_lock(rq);
@@ -7611,10 +7609,28 @@ timeout_proc(Process* p)
     p->flags |= F_TIMO;
     p->flags &= ~F_INSLPQUEUE;
 
-    if (p->status == P_WAITING)
-	erts_add_to_runq(p); 
-    if (p->status == P_SUSPENDED)
+    switch (p->status) {
+    case P_GARBING:
+	switch (p->gcstatus) {
+	case P_SUSPENDED:
+	    goto suspended;
+	case P_WAITING:
+	    goto waiting;
+	default:
+	    break;
+	}
+	break;
+    case P_WAITING:
+    waiting:
+	erts_add_to_runq(p);
+	break;
+    case P_SUSPENDED:
+    suspended:
 	p->rstatus = P_RUNABLE;   /* MUST set resume status to runnable */
+	break;
+    default:
+	break;
+    }
 }
 
 
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 8f78a7d76e..334ae5573f 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -895,6 +895,7 @@ extern struct erts_system_profile_flags_t erts_system_profile_flags;
 #define F_HAVE_BLCKD_MSCHED  (1 <<  8) /* Process has blocked multi-scheduling */
 #define F_P2PNR_RESCHED      (1 <<  9) /* Process has been rescheduled via erts_pid2proc_not_running() */
 #define F_FORCE_GC           (1 << 10) /* Force gc at process in-scheduling */
+#define F_HIBERNATE_SCHED    (1 << 11) /* Schedule out after hibernate op */
 
 /* process trace_flags */
 #define F_SENSITIVE          (1 << 0)
diff --git a/erts/emulator/test/process_SUITE.erl b/erts/emulator/test/process_SUITE.erl
index a731f09e4c..36bae908aa 100644
--- a/erts/emulator/test/process_SUITE.erl
+++ b/erts/emulator/test/process_SUITE.erl
@@ -39,6 +39,7 @@
 	 process_info_other_dist_msg/1,
 	 process_info_2_list/1, process_info_lock_reschedule/1,
 	 process_info_lock_reschedule2/1,
+	 process_info_lock_reschedule3/1,
 	 bump_reductions/1, low_prio/1, binary_owner/1, yield/1, yield2/1,
 	 process_status_exiting/1,
 	 otp_4725/1, bad_register/1, garbage_collect/1, otp_6237/1,
@@ -65,7 +66,8 @@ all() ->
      t_process_info, process_info_other_msg,
      process_info_other_dist_msg, process_info_2_list,
      process_info_lock_reschedule,
-     process_info_lock_reschedule2, process_status_exiting,
+     process_info_lock_reschedule2,
+     process_info_lock_reschedule3, process_status_exiting,
      bump_reductions, low_prio, yield, yield2, otp_4725,
      bad_register, garbage_collect, process_info_messages,
      process_flag_badarg, process_flag_heap_size,
@@ -702,6 +704,52 @@ process_info_lock_reschedule2(Config) when is_list(Config) ->
     ?line unlink(P6), exit(P6, bang),
     ?line ok.
 
+many_args(0,_B,_C,_D,_E,_F,_G,_H,_I,_J) ->
+    ok;
+many_args(A,B,C,D,E,F,G,H,I,J) ->
+    many_args(A-1,B,C,D,E,F,G,H,I,J).
+
+do_pi_msg_len(PT, AT) ->
+    lists:map(fun (_) -> ok end, [a,b,c,d]),
+    {message_queue_len, _} = process_info(element(2,PT), element(2,AT)).
+    
+process_info_lock_reschedule3(doc) ->
+    [];
+process_info_lock_reschedule3(suite) ->
+    [];
+process_info_lock_reschedule3(Config) when is_list(Config) ->
+    %% We need a process that is running and an item that requires
+    %% process_info to take the main process lock.
+    ?line Target1 = spawn_link(fun tok_loop/0),
+    ?line Name1 = process_info_lock_reschedule_running,
+    ?line register(Name1, Target1),
+    ?line Target2 = spawn_link(fun () -> receive after infinity -> ok end end),
+    ?line Name2 = process_info_lock_reschedule_waiting,
+    ?line register(Name2, Target2),
+    ?line PI = fun(N) ->
+		       case N rem 10 of
+			   0 -> erlang:yield();
+			   _ -> ok
+		       end,
+		       ?line do_pi_msg_len({proc, Target1},
+					   {arg, message_queue_len})
+	       end,
+    ?line many_args(100000,1,2,3,4,5,6,7,8,9),
+    ?line lists:foreach(PI, lists:seq(1,1000000)),
+    %% Make sure Target1 still is willing to "tok loop"
+    ?line case process_info(Target1, status) of
+	      {status, OkStatus} when OkStatus == runnable;
+				      OkStatus == running;
+				      OkStatus == garbage_collecting ->
+		  ?line unlink(Target1),
+		  ?line unlink(Target2),
+		  ?line exit(Target1, bang),
+		  ?line exit(Target2, bang),
+		  ?line OkStatus;
+	      {status, BadStatus} ->
+		  ?line ?t:fail(BadStatus)
+	  end.
+
 process_status_exiting(Config) when is_list(Config) ->
     %% Make sure that erts_debug:get_internal_state({process_status,P})
     %% returns exiting if it is in status P_EXITING.