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
|
(************************************************************************)
(* v * The Coq Proof Assistant / The Coq Development Team *)
(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2015 *)
(* \VV/ **************************************************************)
(* // * This file is distributed under the terms of the *)
(* * GNU Lesser General Public License Version 2.1 *)
(************************************************************************)
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
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)) ({ contents = (l, rel) } as t) =
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 ({ contents = (xs, rel) } as t) x =
incr age;
(* re-roting the whole list is not the most efficient way... *)
t := (List.sort rel (xs @ [!age,x]), rel)
let clear ({ contents = (l, rel) } as t) = t := ([], rel)
let set_rel rel ({ contents = (xs, _) } as t) =
let rel (_,x) (_,y) = rel x y in
t := (List.sort rel xs, rel)
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)
({ queue = q; lock = m; cond = c; cond_waiting = cn } as tq)
=
Mutex.lock m;
if tq.release then (Mutex.unlock m; 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 (Mutex.unlock m; raise BeingDestroyed)
done;
if !destroy then (Mutex.unlock m; raise BeingDestroyed);
let x = PriorityQueue.pop ~picky q in
Condition.signal c;
Condition.signal cn;
Mutex.unlock m;
x
let broadcast { lock = m; cond = c } =
Mutex.lock m;
Condition.broadcast c;
Mutex.unlock m
let push { queue = q; lock = m; cond = c; release } x =
if release then Errors.anomaly(Pp.str
"TQueue.push while being destroyed! Only 1 producer/destroyer allowed");
Mutex.lock m;
PriorityQueue.push q x;
Condition.broadcast c;
Mutex.unlock m
let clear { queue = q; lock = m; cond = c } =
Mutex.lock m;
PriorityQueue.clear q;
Mutex.unlock m
let is_empty { queue = q } = PriorityQueue.is_empty q
let destroy tq =
tq.release <- true;
while tq.nwaiting > 0 do
Mutex.lock tq.lock;
Condition.broadcast tq.cond;
Mutex.unlock tq.lock;
done;
tq.release <- false
let wait_until_n_are_waiting_and_queue_empty j tq =
Mutex.lock tq.lock;
while not (PriorityQueue.is_empty tq.queue) || tq.nwaiting < j do
Condition.wait tq.cond_waiting tq.lock
done;
Mutex.unlock tq.lock
let wait_until_n_are_waiting_then_snapshot j tq =
let l = ref [] in
Mutex.lock tq.lock;
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;
Mutex.unlock tq.lock;
List.rev !l
let set_order tq rel =
Mutex.lock tq.lock;
PriorityQueue.set_rel rel tq.queue;
Mutex.unlock tq.lock
|
