1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
(************************************************************************)
(* * The Coq Proof Assistant / The Coq Development Team *)
(* v * Copyright INRIA, CNRS and contributors *)
(* <O___,, * (see version control and CREDITS file for authors & dates) *)
(* \VV/ **************************************************************)
(* // * This file is distributed under the terms of the *)
(* * GNU Lesser General Public License Version 2.1 *)
(* * (see LICENSE file for the text of the license) *)
(************************************************************************)
module PriorityQueue : sig
type 'a t
val create : unit -> 'a t
val set_rel : ('a -> 'a -> int) -> 'a t -> unit
val is_empty : 'a t -> bool
val exists : ('a -> bool) -> 'a t -> bool
val pop : ?picky:('a -> bool) -> 'a t -> 'a
val push : 'a t -> 'a -> unit
val clear : 'a t -> unit
val length : 'a t -> int
end = struct
type 'a item = int * 'a
type 'a rel = 'a item -> 'a item -> int
type 'a t = ('a item list * 'a rel) ref
let sort_timestamp (i,_) (j,_) = i - j
let age = ref 0
let create () = ref ([],sort_timestamp)
let is_empty t = fst !t = []
let exists p t = List.exists (fun (_,x) -> p x) (fst !t)
let pop ?(picky=(fun _ -> true)) t =
let (l, rel) = !t in
let rec aux acc = function
| [] -> raise Queue.Empty
| (_,x) :: xs when picky x -> t := (List.rev acc @ xs, rel); x
| (_,x) as hd :: xs -> aux (hd :: acc) xs in
aux [] l
let push t x =
let (xs, rel) = !t in
incr age;
(* re-roting the whole list is not the most efficient way... *)
t := (List.sort rel (xs @ [!age,x]), rel)
let clear t = t := ([], snd !t)
let set_rel rel t =
let rel (_,x) (_,y) = rel x y in
t := (List.sort rel (fst !t), rel)
let length t = List.length (fst !t)
end
type 'a t = {
queue: 'a PriorityQueue.t;
lock : Mutex.t;
cond : Condition.t;
mutable nwaiting : int;
cond_waiting : Condition.t;
mutable release : bool;
}
exception BeingDestroyed
let create () = {
queue = PriorityQueue.create ();
lock = Mutex.create ();
cond = Condition.create ();
nwaiting = 0;
cond_waiting = Condition.create ();
release = false;
}
let pop ?(picky=(fun _ -> true)) ?(destroy=ref false) tq =
let { queue = q; lock = m; cond = c; cond_waiting = cn } = tq in
CThread.with_lock m ~scope:(fun () ->
if tq.release then raise BeingDestroyed;
while not (PriorityQueue.exists picky q || !destroy) do
tq.nwaiting <- tq.nwaiting + 1;
Condition.broadcast cn;
Condition.wait c m;
tq.nwaiting <- tq.nwaiting - 1;
if tq.release || !destroy then raise BeingDestroyed
done;
if !destroy then raise BeingDestroyed;
let x = PriorityQueue.pop ~picky q in
Condition.signal c;
Condition.signal cn;
x)
let broadcast tq =
let { lock = m; cond = c } = tq in
CThread.with_lock m ~scope:(fun () ->
Condition.broadcast c)
let push tq x =
let { queue = q; lock = m; cond = c; release } = tq in
if release then CErrors.anomaly(Pp.str
"TQueue.push while being destroyed! Only 1 producer/destroyer allowed.");
CThread.with_lock m ~scope:(fun () ->
PriorityQueue.push q x;
Condition.broadcast c)
let length tq =
let { queue = q; lock = m } = tq in
CThread.with_lock m ~scope:(fun () ->
PriorityQueue.length q)
let clear tq =
let { queue = q; lock = m; cond = c } = tq in
CThread.with_lock m ~scope:(fun () ->
PriorityQueue.clear q)
let clear_saving tq f =
let { queue = q; lock = m; cond = c } = tq in
let saved = ref [] in
CThread.with_lock m ~scope:(fun () ->
while not (PriorityQueue.is_empty q) do
let elem = PriorityQueue.pop q in
match f elem with
| Some x -> saved := x :: !saved
| None -> ()
done);
List.rev !saved
let is_empty tq = PriorityQueue.is_empty tq.queue
let destroy tq =
tq.release <- true;
while tq.nwaiting > 0 do
CThread.with_lock tq.lock ~scope:(fun () ->
Condition.broadcast tq.cond)
done;
tq.release <- false
let wait_until_n_are_waiting_and_queue_empty j tq =
CThread.with_lock tq.lock ~scope:(fun () ->
while not (PriorityQueue.is_empty tq.queue) || tq.nwaiting < j do
Condition.wait tq.cond_waiting tq.lock
done)
let wait_until_n_are_waiting_then_snapshot j tq =
let l = ref [] in
CThread.with_lock tq.lock ~scope:(fun () ->
while not (PriorityQueue.is_empty tq.queue) do
l := PriorityQueue.pop tq.queue :: !l
done;
while tq.nwaiting < j do Condition.wait tq.cond_waiting tq.lock done;
List.iter (PriorityQueue.push tq.queue) (List.rev !l);
if !l <> [] then Condition.broadcast tq.cond);
List.rev !l
let set_order tq rel =
CThread.with_lock tq.lock ~scope:(fun () ->
PriorityQueue.set_rel rel tq.queue)
|
