1 (* Title: Pure/Concurrent/task_queue.ML
4 Ordered queue of grouped tasks.
11 val name_of_task: task -> string
12 val pri_of_task: task -> int
13 val str_of_task: task -> string
14 val timing_of_task: task -> Time.time * Time.time * string list
16 val new_group: group option -> group
17 val group_id: group -> int
18 val eq_group: group * group -> bool
19 val cancel_group: group -> exn -> unit
20 val is_canceled: group -> bool
21 val group_status: group -> exn list
22 val str_of_group: group -> string
25 val all_passive: queue -> bool
26 val status: queue -> {ready: int, pending: int, running: int, passive: int}
27 val cancel: queue -> group -> bool
28 val cancel_all: queue -> group list
29 val finish: task -> queue -> bool * queue
30 val enqueue_passive: group -> (unit -> bool) -> queue -> task * queue
31 val enqueue: string -> group -> task list -> int -> (bool -> bool) ->
32 queue -> (task * bool) * queue
33 val extend: task -> (bool -> bool) -> queue -> queue option
34 val dequeue_passive: Thread.thread -> task -> queue -> bool * queue
35 val dequeue: Thread.thread -> queue -> (task * group * (bool -> bool) list) option * queue
37 val init_deps: task list -> deps
38 val finished_deps: deps -> bool
39 val dequeue_deps: Thread.thread -> deps -> queue ->
40 (((task * group * (bool -> bool) list) option * deps) * queue)
41 val running: task -> (unit -> 'a) -> 'a
42 val joining: task -> (unit -> 'a) -> 'a
43 val waiting: task -> deps -> (unit -> 'a) -> 'a
46 structure Task_Queue: TASK_QUEUE =
49 val new_id = Synchronized.counter ();
56 type timing = Time.time * Time.time * string list; (*run, wait, wait dependencies*)
59 Synchronized.var "timing" ((Time.zeroTime, Time.zeroTime, []): timing);
61 abstype task = Task of
65 timing: timing Synchronized.var}
68 val dummy_task = Task {name = "", id = ~1, pri = NONE, timing = new_timing ()};
69 fun new_task name pri = Task {name = name, id = new_id (), pri = pri, timing = new_timing ()};
71 fun name_of_task (Task {name, ...}) = name;
72 fun pri_of_task (Task {pri, ...}) = the_default 0 pri;
73 fun str_of_task (Task {name, id, ...}) =
74 if name = "" then string_of_int id else string_of_int id ^ " (" ^ name ^ ")";
76 fun timing_of_task (Task {timing, ...}) = Synchronized.value timing;
78 fun update_timing update (Task {timing, ...}) e =
80 val start = Time.now ();
81 val result = Exn.capture e ();
82 val t = Time.- (Time.now (), start);
83 val _ = Synchronized.change timing (update t);
84 in Exn.release result end;
86 fun task_ord (Task {id = id1, pri = pri1, ...}, Task {id = id2, pri = pri2, ...}) =
87 prod_ord (rev_order o option_ord int_ord) int_ord ((pri1, id1), (pri2, id2));
89 val eq_task = is_equal o task_ord;
93 structure Task_Graph = Graph(type key = task val ord = task_ord);
98 abstype group = Group of
99 {parent: group option,
101 status: exn list Synchronized.var}
104 fun make_group (parent, id, status) = Group {parent = parent, id = id, status = status};
106 fun new_group parent = make_group (parent, new_id (), Synchronized.var "group" []);
108 fun group_id (Group {id, ...}) = id;
109 fun eq_group (group1, group2) = group_id group1 = group_id group2;
111 fun group_ancestry (Group {parent, id, ...}) =
112 id :: (case parent of NONE => [] | SOME group => group_ancestry group);
117 fun cancel_group (Group {status, ...}) exn =
118 Synchronized.change status
120 if not (Exn.is_interrupt exn) orelse null exns then exn :: exns
123 fun is_canceled (Group {parent, status, ...}) =
124 not (null (Synchronized.value status)) orelse
125 (case parent of NONE => false | SOME group => is_canceled group);
127 fun group_status (Group {parent, status, ...}) =
128 Synchronized.value status @
129 (case parent of NONE => [] | SOME group => group_status group);
131 fun str_of_group group =
132 (is_canceled group ? enclose "(" ")") (string_of_int (group_id group));
137 (** queue of jobs and groups **)
142 Job of (bool -> bool) list |
143 Running of Thread.thread |
144 Passive of unit -> bool;
146 type jobs = (group * job) Task_Graph.T;
148 fun get_group (jobs: jobs) task = #1 (Task_Graph.get_node jobs task);
149 fun get_job (jobs: jobs) task = #2 (Task_Graph.get_node jobs task);
150 fun set_job task job (jobs: jobs) = Task_Graph.map_node task (fn (group, _) => (group, job)) jobs;
152 fun add_job task dep (jobs: jobs) =
153 Task_Graph.add_edge (dep, task) jobs handle Task_Graph.UNDEF _ => jobs;
155 fun get_deps (jobs: jobs) task =
156 Task_Graph.imm_preds jobs task handle Task_Graph.UNDEF _ => [];
161 datatype queue = Queue of
162 {groups: task list Inttab.table, (*groups with presently active members*)
163 jobs: jobs}; (*job dependency graph*)
165 fun make_queue groups jobs = Queue {groups = groups, jobs = jobs};
167 val empty = make_queue Inttab.empty Task_Graph.empty;
172 fun ready_job task ((group, Job list), ([], _)) = SOME (task, group, rev list)
173 | ready_job task ((group, Passive abort), ([], _)) =
174 if is_canceled group then SOME (task, group, [fn _ => abort ()])
176 | ready_job _ _ = NONE;
178 fun active_job (_, Job _) = SOME ()
179 | active_job (_, Running _) = SOME ()
180 | active_job (group, Passive _) = if is_canceled group then SOME () else NONE;
182 fun all_passive (Queue {jobs, ...}) =
183 is_none (Task_Graph.get_first (active_job o #1 o #2) jobs);
188 fun status (Queue {jobs, ...}) =
191 Task_Graph.fold (fn (_, ((_, job), (deps, _))) => fn (x, y, z, w) =>
193 Job _ => if null deps then (x + 1, y, z, w) else (x, y + 1, z, w)
194 | Running _ => (x, y, z + 1, w)
195 | Passive _ => (x, y, z, w + 1)))
197 in {ready = x, pending = y, running = z, passive = w} end;
201 (** task queue operations **)
203 (* cancel -- peers and sub-groups *)
205 fun cancel (Queue {groups, jobs}) group =
207 val _ = cancel_group group Exn.Interrupt;
208 val tasks = Inttab.lookup_list groups (group_id group);
210 fold (get_job jobs #> (fn Running t => insert Thread.equal t | _ => I)) tasks [];
211 val _ = List.app Simple_Thread.interrupt running;
214 fun cancel_all (Queue {jobs, ...}) =
216 fun cancel_job (group, job) (groups, running) =
217 (cancel_group group Exn.Interrupt;
219 Running t => (insert eq_group group groups, insert Thread.equal t running)
220 | _ => (groups, running)));
221 val (running_groups, running) = Task_Graph.fold (cancel_job o #1 o #2) jobs ([], []);
222 val _ = List.app Simple_Thread.interrupt running;
223 in running_groups end;
228 fun finish task (Queue {groups, jobs}) =
230 val group = get_group jobs task;
232 |> fold (fn gid => Inttab.remove_list eq_task (gid, task)) (group_ancestry group);
233 val jobs' = Task_Graph.del_node task jobs;
234 val maximal = null (Task_Graph.imm_succs jobs task);
235 in (maximal, make_queue groups' jobs') end;
240 fun enqueue_passive group abort (Queue {groups, jobs}) =
242 val task = new_task "passive" NONE;
244 |> fold (fn gid => Inttab.cons_list (gid, task)) (group_ancestry group);
245 val jobs' = jobs |> Task_Graph.new_node (task, (group, Passive abort));
246 in (task, make_queue groups' jobs') end;
248 fun enqueue name group deps pri job (Queue {groups, jobs}) =
250 val task = new_task name (SOME pri);
252 |> fold (fn gid => Inttab.cons_list (gid, task)) (group_ancestry group);
254 |> Task_Graph.new_node (task, (group, Job [job]))
255 |> fold (add_job task) deps
256 |> fold (fold (add_job task) o get_deps jobs) deps;
257 val minimal = null (get_deps jobs' task);
258 in ((task, minimal), make_queue groups' jobs') end;
260 fun extend task job (Queue {groups, jobs}) =
261 (case try (get_job jobs) task of
262 SOME (Job list) => SOME (make_queue groups (set_job task (Job (job :: list)) jobs))
268 fun dequeue_passive thread task (queue as Queue {groups, jobs}) =
269 (case try (get_job jobs) task of
271 let val jobs' = set_job task (Running thread) jobs
272 in (true, make_queue groups jobs') end
273 | _ => (false, queue));
275 fun dequeue thread (queue as Queue {groups, jobs}) =
276 (case Task_Graph.get_first (uncurry ready_job) jobs of
277 SOME (result as (task, _, _)) =>
278 let val jobs' = set_job task (Running thread) jobs
279 in (SOME result, make_queue groups jobs') end
280 | NONE => (NONE, queue));
283 (* dequeue wrt. dynamic dependencies *)
285 abstype deps = Deps of task list
288 fun init_deps tasks = Deps tasks;
289 fun finished_deps (Deps tasks) = null tasks;
291 fun insert_deps (Deps tasks) = fold (insert (op =) o name_of_task) tasks;
293 fun dequeue_deps thread (Deps deps) (queue as Queue {groups, jobs}) =
295 fun ready task = ready_job task (Task_Graph.get_entry jobs task);
296 val tasks = filter (can (Task_Graph.get_node jobs)) deps;
297 fun result (res as (task, _, _)) =
298 let val jobs' = set_job task (Running thread) jobs
299 in ((SOME res, Deps tasks), make_queue groups jobs') end;
301 (case get_first ready tasks of
302 SOME res => result res
304 (case get_first (get_first ready o get_deps jobs) tasks of
305 SOME res => result res
306 | NONE => ((NONE, Deps tasks), queue)))
315 update_timing (fn t => fn (a, b, ds) => (Time.+ (a, t), b, ds)) task;
318 update_timing (fn t => fn (a, b, ds) => (Time.- (a, t), b, ds)) task;
320 fun waiting task deps =
321 update_timing (fn t => fn (a, b, ds) => (Time.- (a, t), Time.+ (b, t), insert_deps deps ds)) task;