Paranoid RunQueue errors. (#27948)

* Verbose RunQueue errors.

* Looser tracking

* Add line numbers.

* Point fingers at subsystems.

* SSinput debugging, useless debugging cleanup

code/controllers/master.dm

@@ -49,8 +49,8 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 	/// Did inits finish with no one logged in
 	var/initializations_finished_with_no_players_logged_in
 
-	/// The type of the last subsystem to be fire()'d.
-	var/last_type_processed
+	/// The last subsystem to be fire()'d.
+	var/datum/controller/subsystem/last_processed
 
 	/// Cache for the loading screen - cleared after
 	var/list/ss_in_init_order = list()
@@ -172,7 +172,7 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 					msg += "\t [varname] = [varval]\n"
 	log_world(msg)
 
-	var/datum/controller/subsystem/BadBoy = Master.last_type_processed
+	var/datum/controller/subsystem/BadBoy = Master.last_processed
 	var/FireHim = FALSE
 	if(istype(BadBoy))
 		msg = null
@@ -431,8 +431,8 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 			continue
 
 		if(queue_head)
-			if(RunQueue() <= 0) //error running queue
-				stack_trace("MC: RunQueue failed. Current error_level is [round(error_level, 0.25)]")
+			if(!RunQueue())
+				stack_trace("MC: RunQueue returned early during [last_processed.name] ([last_processed.last_task()]). Current error_level is [round(error_level, 0.25)].")
 				if(error_level > 1) //skip the first error,
 					if(!SoftReset(tickersubsystems, runlevel_sorted_subsystems))
 						error_level++
@@ -501,7 +501,6 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 /// RunQueue - Run thru the queue of subsystems to run, running them while balancing out their allocated tick precentage
 /// Returns 0 if runtimed, a negitive number for logic errors, and a positive number if the operation completed without errors
 /datum/controller/master/proc/RunQueue()
-	. = 0
 	var/datum/controller/subsystem/queue_node
 	var/queue_node_flags
 	var/queue_node_priority
@@ -537,9 +536,9 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 					bg_calc = TRUE
 			else if(bg_calc)
 				//error state, do sane fallback behavior
-				if(. == 0)
-					log_world("MC: Queue logic failure, non-background subsystem queued to run after a background subsystem: [queue_node] queue_prev:[queue_node.queue_prev]")
-				. = -1
+				var/message = "MC: Queue logic failure, non-background subsystem queued to run after a background subsystem: [queue_node] queue_prev:[queue_node.queue_prev]"
+				log_world(message)
+				stack_trace(message)
 				current_tick_budget = queue_priority_count //this won't even be right, but is the best we have.
 				bg_calc = FALSE
 
@@ -551,9 +550,9 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 				tick_precentage = tick_remaining * (queue_node_priority / current_tick_budget)
 			else
 				//error state
-				if(. == 0)
-					log_world("MC: tick_budget sync error. [json_encode(list(current_tick_budget, queue_priority_count, queue_priority_count_bg, bg_calc, queue_node, queue_node_priority))]")
-				. = -1
+				var/message = "MC: tick_budget sync error. [json_encode(list(current_tick_budget, queue_priority_count, queue_priority_count_bg, bg_calc, queue_node, queue_node_priority))]"
+				log_world(message)
+				stack_trace(message)
 				tick_precentage = tick_remaining //just because we lost track of priority calculations doesn't mean we can't try to finish off the run, if the error state persists, we don't want to stop ticks from happening
 
 			tick_precentage = max(tick_precentage*0.5, tick_precentage-queue_node.tick_overrun)
@@ -563,7 +562,7 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 			ran = TRUE
 
 			queue_node_paused = (queue_node.state == SS_PAUSED || queue_node.state == SS_PAUSING)
-			last_type_processed = queue_node
+			last_processed = queue_node
 
 			queue_node.state = SS_RUNNING
 
@@ -613,8 +612,7 @@ GLOBAL_REAL(Master, /datum/controller/master) = new
 
 			queue_node = queue_node.queue_next
 
-	if(. == 0)
-		. = 1
+	return TRUE
 
 //resets the queue, and all subsystems, while filtering out the subsystem lists
 // called if any mc's queue procs runtime or exit improperly.

code/controllers/subsystem.dm

@@ -353,3 +353,7 @@
 	out["sleep_count"] = fire_sleep_count
 	out["custom"] = list() // Override as needed on child
 	return out
+
+/// Allows a subsystem to report what it was doing in case of a silent crash.
+/datum/controller/subsystem/proc/last_task()
+	return "No task specified."

code/controllers/subsystem/SSinput.dm

@@ -15,6 +15,11 @@ SUBSYSTEM_DEF(input)
 	/// List of clients whose input to process in loop.
 	var/list/client/processing = list()
 
+	var/last_ckey
+	var/last_x
+	var/last_y
+	var/last_z
+
 /datum/controller/subsystem/input/Initialize()
 	refresh_client_macro_sets()
 
@@ -26,6 +31,10 @@ SUBSYSTEM_DEF(input)
 	set waitfor = FALSE
 	var/list/to_cull
 	for(var/client/C in processing)
+		last_ckey = C.ckey
+		last_x = C.mob?.x
+		last_y = C.mob?.y
+		last_z = C.mob?.z
 		if(processing[C] + AUTO_CULL_TIME < world.time)
 			if(!length(C.input_data.keys_held))
 				LAZYADD(to_cull, C)
@@ -42,4 +51,7 @@ SUBSYSTEM_DEF(input)
 		var/client/user = clients[i]
 		user.set_macros()
 
+/datum/controller/subsystem/input/last_task()
+	return "[last_ckey] at [last_x], [last_y], [last_z]"
+
 #undef AUTO_CULL_TIME