Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source
Page
Library
Module
Module type
Parameter
Class
Class type
Source
scheduler.ml
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216
open Stdune open Core type fill = Fill : 'a ivar * 'a -> fill module Jobs = struct type t = | Empty | Job : context * ('a -> eff) * 'a * t -> t | Concat : t * t -> t let concat a b = match (a, b) with | Empty, x | x, Empty -> x | _ -> Concat (a, b) let rec enqueue_readers (readers : (_, [ `Empty ]) ivar_state) x jobs = match readers with | Empty -> jobs | Empty_with_readers (ctx, k, readers) -> enqueue_readers readers x (Job (ctx, k, x, jobs)) let fill_ivar ivar x jobs = match ivar.state with | Full _ -> failwith "Fiber.Ivar.fill" | Empty -> ivar.state <- Full x; jobs | Empty_with_readers (ctx, k, readers) -> ivar.state <- Full x; let jobs = Job (ctx, k, x, jobs) in enqueue_readers readers x jobs let rec exec_fills fills acc = match fills with | [] -> acc | Fill (ivar, x) :: fills -> let acc = fill_ivar ivar x acc in exec_fills fills acc let exec_fills fills = exec_fills (List.rev fills) Empty end type step' = | Done of value | Stalled module type Witness = sig type t type value += X of t end type 'a stalled = (module Witness with type t = 'a) type 'a step = | Done of 'a | Stalled of 'a stalled let rec loop : Jobs.t -> step' = function | Empty -> Stalled | Job (ctx, run, x, jobs) -> exec ctx run x jobs | Concat (a, b) -> loop2 a b and loop2 a b = match a with | Empty -> loop b | Job (ctx, run, x, a) -> exec ctx run x (Jobs.concat a b) | Concat (a1, a2) -> loop2 a1 (Jobs.concat a2 b) and exec : 'a. context -> ('a -> eff) -> 'a -> Jobs.t -> step' = fun ctx k x jobs -> match k x with | exception exn -> let exn = Exn_with_backtrace.capture exn in exec ctx.on_error.ctx ctx.on_error.run exn jobs | Done v -> Done v | Toplevel_exception exn -> Exn_with_backtrace.reraise exn | Unwind (k, x) -> exec ctx.parent k x jobs | Read_ivar (ivar, k) -> ( match ivar.state with | (Empty | Empty_with_readers _) as readers -> ivar.state <- Empty_with_readers (ctx, k, readers); loop jobs | Full x -> exec ctx k x jobs) | Fill_ivar (ivar, x, k) -> let jobs = Jobs.concat jobs (Jobs.fill_ivar ivar x Empty) in exec ctx k () jobs | Suspend (f, k) -> let k = { ctx; run = k } in f k; loop jobs | Resume (suspended, x, k) -> exec ctx k () (Jobs.concat jobs (Job (suspended.ctx, suspended.run, x, Empty))) | Get_var (key, k) -> exec ctx k (Univ_map.find ctx.vars key) jobs | Set_var (key, x, k) -> let ctx = { ctx with parent = ctx; vars = Univ_map.set ctx.vars key x } in exec ctx k () jobs | Unset_var (key, k) -> let ctx = { ctx with parent = ctx; vars = Univ_map.remove ctx.vars key } in exec ctx k () jobs | With_error_handler (on_error, k) -> let on_error = { ctx; run = (fun exn -> on_error exn Nothing.unreachable_code) } in let ctx = { ctx with parent = ctx; on_error } in exec ctx k () jobs | Map_reduce_errors (m, on_error, f, k) -> map_reduce_errors ctx m on_error f k jobs | End_of_fiber () -> let (Map_reduce_context r) = ctx.map_reduce_context in deref r jobs | Unwind_map_reduce (k, x) -> let (Map_reduce_context r) = ctx.map_reduce_context in let ref_count = r.ref_count - 1 in r.ref_count <- ref_count; assert (ref_count = 0); exec ctx.parent k x jobs | End_of_map_reduce_error_handler map_reduce_context -> deref map_reduce_context jobs | Never () -> loop jobs | Fork (a, b) -> let (Map_reduce_context r) = ctx.map_reduce_context in r.ref_count <- r.ref_count + 1; exec ctx Fun.id a (Job (ctx, b, (), jobs)) | Reraise exn -> let { ctx; run } = ctx.on_error in exec ctx run exn jobs | Reraise_all exns -> ( match length_and_rev exns with | 0, _ -> loop jobs | n, exns -> let (Map_reduce_context r) = ctx.map_reduce_context in r.ref_count <- r.ref_count + (n - 1); let { ctx; run } = ctx.on_error in let jobs = List.fold_left exns ~init:jobs ~f:(fun jobs exn -> Jobs.Job (ctx, run, exn, jobs)) in loop jobs) and deref : 'a 'b. ('a, 'b) map_reduce_context' -> Jobs.t -> step' = fun r jobs -> let ref_count = r.ref_count - 1 in r.ref_count <- ref_count; match ref_count with | 0 -> exec r.k.ctx r.k.run (Error r.errors) jobs | _ -> assert (ref_count > 0); loop jobs and map_reduce_errors : type errors b. context -> (module Monoid with type t = errors) -> (Exn_with_backtrace.t -> errors t) -> (unit -> eff) -> ((b, errors) result -> eff) -> Jobs.t -> step' = fun ctx (module M : Monoid with type t = errors) on_error f k jobs -> let map_reduce_context = { k = { ctx; run = k }; ref_count = 1; errors = M.empty } in let on_error = { ctx ; run = (fun exn -> on_error exn (fun m -> map_reduce_context.errors <- M.combine map_reduce_context.errors m; End_of_map_reduce_error_handler map_reduce_context)) } in let ctx = { ctx with parent = ctx ; on_error ; map_reduce_context = Map_reduce_context map_reduce_context } in exec ctx f () jobs let repack_step (type a) (module W : Witness with type t = a) (step' : step') = match step' with | Done (W.X a) -> Done a | Done _ -> Code_error.raise "advance: it's illegal to call advance with a fiber created in a \ different scheduler" [] | Stalled -> Stalled (module W) let advance (type a) (module W : Witness with type t = a) fill : a step = fill |> Nonempty_list.to_list |> Jobs.exec_fills |> loop |> repack_step (module W) let start (type a) (t : a t) = let module W = struct type t = a type value += X of a end in let rec ctx = { parent = ctx ; on_error = { ctx; run = (fun exn -> Toplevel_exception exn) } ; vars = Univ_map.empty ; map_reduce_context = Map_reduce_context { k = { ctx; run = (fun _ -> assert false) } ; ref_count = 1 ; errors = () } } in exec ctx t (fun x -> Done (W.X x)) Empty |> repack_step (module W)