742 lines
30 KiB
Rust
742 lines
30 KiB
Rust
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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/*!**************************************************************************
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* Spawning & linked failure
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*
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* Several data structures are involved in task management to allow properly
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* propagating failure across linked/supervised tasks.
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*
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* (1) The "taskgroup_arc" is an unsafe::exclusive which contains a hashset of
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* all tasks that are part of the group. Some tasks are 'members', which
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* means if they fail, they will kill everybody else in the taskgroup.
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* Other tasks are 'descendants', which means they will not kill tasks
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* from this group, but can be killed by failing members.
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*
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* A new one of these is created each spawn_linked or spawn_supervised.
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*
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* (2) The "tcb" is a per-task control structure that tracks a task's spawn
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* configuration. It contains a reference to its taskgroup_arc, a
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* reference to its node in the ancestor list (below), a flag for
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* whether it's part of the 'main'/'root' taskgroup, and an optionally
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* configured notification port. These are stored in TLS.
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*
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* (3) The "ancestor_list" is a cons-style list of unsafe::exclusives which
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* tracks 'generations' of taskgroups -- a group's ancestors are groups
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* which (directly or transitively) spawn_supervised-ed them. Each task
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* is recorded in the 'descendants' of each of its ancestor groups.
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*
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* Spawning a supervised task is O(n) in the number of generations still
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* alive, and exiting (by success or failure) that task is also O(n).
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*
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* This diagram depicts the references between these data structures:
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*
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* linked_________________________________
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* ___/ _________ \___
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* / \ | group X | / \
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* ( A ) - - - - - - - > | {A,B} {}|< - - -( B )
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* \___/ |_________| \___/
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* unlinked
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* | __ (nil)
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* | //| The following code causes this:
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* |__ // /\ _________
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* / \ // || | group Y | fn taskA() {
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* ( C )- - - ||- - - > |{C} {D,E}| spawn(taskB);
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* \___/ / \=====> |_________| spawn_unlinked(taskC);
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* supervise /gen \ ...
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* | __ \ 00 / }
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* | //| \__/ fn taskB() { ... }
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* |__ // /\ _________ fn taskC() {
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* / \/ || | group Z | spawn_supervised(taskD);
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* ( D )- - - ||- - - > | {D} {E} | ...
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* \___/ / \=====> |_________| }
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* supervise /gen \ fn taskD() {
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* | __ \ 01 / spawn_supervised(taskE);
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* | //| \__/ ...
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* |__ // _________ }
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* / \/ | group W | fn taskE() { ... }
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* ( E )- - - - - - - > | {E} {} |
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* \___/ |_________|
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*
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* "tcb" "taskgroup_arc"
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* "ancestor_list"
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*
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****************************************************************************/
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#[doc(hidden)]; // FIXME #3538
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use cast;
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use cell::Cell;
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use container::Map;
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use option;
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use comm::{Chan, GenericChan, GenericPort, Port, stream};
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use pipes;
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use prelude::*;
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use unstable;
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use ptr;
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use hashmap::linear::LinearSet;
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use task::local_data_priv::{local_get, local_set};
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use task::rt::rust_task;
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use task::rt::rust_closure;
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use task::rt;
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use task::{Failure, ManualThreads, PlatformThread, SchedOpts, SingleThreaded};
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use task::{Success, TaskOpts, TaskResult, ThreadPerCore, ThreadPerTask};
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use task::{ExistingScheduler, SchedulerHandle};
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use task::{default_task_opts, unkillable};
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use uint;
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use util;
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macro_rules! move_it (
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{ $x:expr } => ( unsafe { let y = *ptr::addr_of(&($x)); y } )
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)
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type TaskSet = LinearSet<*rust_task>;
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fn new_taskset() -> TaskSet {
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LinearSet::new()
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}
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fn taskset_insert(tasks: &mut TaskSet, task: *rust_task) {
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let didnt_overwrite = tasks.insert(task);
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assert didnt_overwrite;
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}
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fn taskset_remove(tasks: &mut TaskSet, task: *rust_task) {
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let was_present = tasks.remove(&task);
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assert was_present;
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}
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pub fn taskset_each(tasks: &TaskSet, blk: fn(v: *rust_task) -> bool) {
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tasks.each(|k| blk(*k))
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}
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// One of these per group of linked-failure tasks.
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struct TaskGroupData {
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// All tasks which might kill this group. When this is empty, the group
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// can be "GC"ed (i.e., its link in the ancestor list can be removed).
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mut members: TaskSet,
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// All tasks unidirectionally supervised by (directly or transitively)
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// tasks in this group.
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mut descendants: TaskSet,
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}
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type TaskGroupArc = unstable::Exclusive<Option<TaskGroupData>>;
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type TaskGroupInner = &mut Option<TaskGroupData>;
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// A taskgroup is 'dead' when nothing can cause it to fail; only members can.
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pure fn taskgroup_is_dead(tg: &TaskGroupData) -> bool {
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(&tg.members).is_empty()
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}
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// A list-like structure by which taskgroups keep track of all ancestor groups
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// which may kill them. Needed for tasks to be able to remove themselves from
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// ancestor groups upon exit. The list has a node for each "generation", and
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// ends either at the root taskgroup (which has no ancestors) or at a
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// taskgroup which was spawned-unlinked. Tasks from intermediate generations
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// have references to the middle of the list; when intermediate generations
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// die, their node in the list will be collected at a descendant's spawn-time.
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struct AncestorNode {
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// Since the ancestor list is recursive, we end up with references to
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// exclusives within other exclusives. This is dangerous business (if
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// circular references arise, deadlock and memory leaks are imminent).
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// Hence we assert that this counter monotonically decreases as we
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// approach the tail of the list.
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// FIXME(#3068): Make the generation counter togglable with #[cfg(debug)].
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generation: uint,
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// Should really be an immutable non-option. This way appeases borrowck.
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mut parent_group: Option<TaskGroupArc>,
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// Recursive rest of the list.
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mut ancestors: AncestorList,
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}
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enum AncestorList = Option<unstable::Exclusive<AncestorNode>>;
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// Accessors for taskgroup arcs and ancestor arcs that wrap the unsafety.
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#[inline(always)]
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fn access_group<U>(x: &TaskGroupArc, blk: fn(TaskGroupInner) -> U) -> U {
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unsafe { x.with(blk) }
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}
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#[inline(always)]
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fn access_ancestors<U>(x: &unstable::Exclusive<AncestorNode>,
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blk: fn(x: &mut AncestorNode) -> U) -> U {
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unsafe { x.with(blk) }
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}
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// Iterates over an ancestor list.
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// (1) Runs forward_blk on each ancestral taskgroup in the list
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// (2) If forward_blk "break"s, runs optional bail_blk on all ancestral
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// taskgroups that forward_blk already ran on successfully (Note: bail_blk
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// is NOT called on the block that forward_blk broke on!).
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// (3) As a bonus, coalesces away all 'dead' taskgroup nodes in the list.
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// FIXME(#2190): Change Option<@fn(...)> to Option<&fn(...)>, to save on
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// allocations. Once that bug is fixed, changing the sigil should suffice.
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fn each_ancestor(list: &mut AncestorList,
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bail_opt: Option<@fn(TaskGroupInner)>,
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forward_blk: fn(TaskGroupInner) -> bool)
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-> bool {
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// "Kickoff" call - there was no last generation.
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return !coalesce(list, bail_opt, forward_blk, uint::max_value);
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// Recursively iterates, and coalesces afterwards if needed. Returns
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// whether or not unwinding is needed (i.e., !successful iteration).
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fn coalesce(list: &mut AncestorList,
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bail_opt: Option<@fn(TaskGroupInner)>,
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forward_blk: fn(TaskGroupInner) -> bool,
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last_generation: uint) -> bool {
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// Need to swap the list out to use it, to appease borrowck.
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let tmp_list = util::replace(&mut *list, AncestorList(None));
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let (coalesce_this, early_break) =
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iterate(&tmp_list, bail_opt, forward_blk, last_generation);
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// What should our next ancestor end up being?
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if coalesce_this.is_some() {
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// Needed coalesce. Our next ancestor becomes our old
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// ancestor's next ancestor. ("next = old_next->next;")
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*list = option::unwrap(coalesce_this);
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} else {
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// No coalesce; restore from tmp. ("next = old_next;")
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*list = tmp_list;
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}
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return early_break;
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}
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// Returns an optional list-to-coalesce and whether unwinding is needed.
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// Option<ancestor_list>:
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// Whether or not the ancestor taskgroup being iterated over is
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// dead or not; i.e., it has no more tasks left in it, whether or not
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// it has descendants. If dead, the caller shall coalesce it away.
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// bool:
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// True if the supplied block did 'break', here or in any recursive
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// calls. If so, must call the unwinder on all previous nodes.
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fn iterate(ancestors: &AncestorList,
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bail_opt: Option<@fn(TaskGroupInner)>,
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forward_blk: &fn(TaskGroupInner) -> bool,
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last_generation: uint)
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-> (Option<AncestorList>, bool) {
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// At each step of iteration, three booleans are at play which govern
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// how the iteration should behave.
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// 'nobe_is_dead' - Should the list should be coalesced at this point?
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// Largely unrelated to the other two.
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// 'need_unwind' - Should we run the bail_blk at this point? (i.e.,
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// do_continue was false not here, but down the line)
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// 'do_continue' - Did the forward_blk succeed at this point? (i.e.,
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// should we recurse? or should our callers unwind?)
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// The map defaults to None, because if ancestors is None, we're at
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// the end of the list, which doesn't make sense to coalesce.
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return do (**ancestors).map_default((None,false)) |ancestor_arc| {
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// NB: Takes a lock! (this ancestor node)
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do access_ancestors(ancestor_arc) |nobe| {
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// Check monotonicity
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assert last_generation > nobe.generation;
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/*##########################################################*
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* Step 1: Look at this ancestor group (call iterator block).
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*##########################################################*/
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let mut nobe_is_dead = false;
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let do_continue =
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// NB: Takes a lock! (this ancestor node's parent group)
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do with_parent_tg(&mut nobe.parent_group) |tg_opt| {
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// Decide whether this group is dead. Note that the
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// group being *dead* is disjoint from it *failing*.
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nobe_is_dead = match *tg_opt {
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Some(ref tg) => taskgroup_is_dead(tg),
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None => nobe_is_dead
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};
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// Call iterator block. (If the group is dead, it's
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// safe to skip it. This will leave our *rust_task
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// hanging around in the group even after it's freed,
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// but that's ok because, by virtue of the group being
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// dead, nobody will ever kill-all (foreach) over it.)
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if nobe_is_dead { true } else { forward_blk(tg_opt) }
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};
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/*##########################################################*
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* Step 2: Recurse on the rest of the list; maybe coalescing.
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*##########################################################*/
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// 'need_unwind' is only set if blk returned true above, *and*
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// the recursive call early-broke.
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let mut need_unwind = false;
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if do_continue {
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// NB: Takes many locks! (ancestor nodes & parent groups)
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need_unwind = coalesce(&mut nobe.ancestors, bail_opt,
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forward_blk, nobe.generation);
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}
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/*##########################################################*
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* Step 3: Maybe unwind; compute return info for our caller.
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*##########################################################*/
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if need_unwind && !nobe_is_dead {
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do bail_opt.iter |bail_blk| {
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do with_parent_tg(&mut nobe.parent_group) |tg_opt| {
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(*bail_blk)(tg_opt)
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}
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}
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}
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// Decide whether our caller should unwind.
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need_unwind = need_unwind || !do_continue;
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// Tell caller whether or not to coalesce and/or unwind
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if nobe_is_dead {
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// Swap the list out here; the caller replaces us with it.
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let rest = util::replace(&mut nobe.ancestors,
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AncestorList(None));
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(Some(rest), need_unwind)
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} else {
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(None, need_unwind)
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}
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}
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};
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// Wrapper around exclusive::with that appeases borrowck.
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fn with_parent_tg<U>(parent_group: &mut Option<TaskGroupArc>,
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blk: fn(TaskGroupInner) -> U) -> U {
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// If this trips, more likely the problem is 'blk' failed inside.
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let tmp_arc = option::swap_unwrap(&mut *parent_group);
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let result = do access_group(&tmp_arc) |tg_opt| { blk(tg_opt) };
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*parent_group = Some(tmp_arc);
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result
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}
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}
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}
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// One of these per task.
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struct TCB {
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me: *rust_task,
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// List of tasks with whose fates this one's is intertwined.
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tasks: TaskGroupArc, // 'none' means the group has failed.
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// Lists of tasks who will kill us if they fail, but whom we won't kill.
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mut ancestors: AncestorList,
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is_main: bool,
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notifier: Option<AutoNotify>,
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}
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impl Drop for TCB {
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// Runs on task exit.
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fn finalize(&self) {
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unsafe {
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// If we are failing, the whole taskgroup needs to die.
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if rt::rust_task_is_unwinding(self.me) {
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self.notifier.iter(|x| { x.failed = true; });
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// Take everybody down with us.
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do access_group(&self.tasks) |tg| {
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kill_taskgroup(tg, self.me, self.is_main);
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}
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} else {
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// Remove ourselves from the group(s).
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do access_group(&self.tasks) |tg| {
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leave_taskgroup(tg, self.me, true);
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}
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}
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// It doesn't matter whether this happens before or after dealing
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// with our own taskgroup, so long as both happen before we die.
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// We remove ourself from every ancestor we can, so no cleanup; no
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// break.
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for each_ancestor(&mut self.ancestors, None) |ancestor_group| {
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leave_taskgroup(ancestor_group, self.me, false);
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};
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}
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}
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}
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fn TCB(me: *rust_task, tasks: TaskGroupArc, ancestors: AncestorList,
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is_main: bool, notifier: Option<AutoNotify>) -> TCB {
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let notifier = notifier;
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notifier.iter(|x| { x.failed = false; });
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TCB {
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me: me,
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tasks: tasks,
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ancestors: ancestors,
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is_main: is_main,
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notifier: notifier
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}
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}
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struct AutoNotify {
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notify_chan: Chan<TaskResult>,
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mut failed: bool,
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}
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impl Drop for AutoNotify {
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fn finalize(&self) {
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let result = if self.failed { Failure } else { Success };
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self.notify_chan.send(result);
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}
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}
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fn AutoNotify(chan: Chan<TaskResult>) -> AutoNotify {
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AutoNotify {
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notify_chan: chan,
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failed: true // Un-set above when taskgroup successfully made.
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}
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}
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fn enlist_in_taskgroup(state: TaskGroupInner, me: *rust_task,
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is_member: bool) -> bool {
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let newstate = util::replace(&mut *state, None);
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// If 'None', the group was failing. Can't enlist.
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if newstate.is_some() {
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let group = option::unwrap(newstate);
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taskset_insert(if is_member { &mut group.members }
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else { &mut group.descendants }, me);
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*state = Some(group);
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true
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} else {
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false
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}
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}
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// NB: Runs in destructor/post-exit context. Can't 'fail'.
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fn leave_taskgroup(state: TaskGroupInner, me: *rust_task,
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is_member: bool) {
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let newstate = util::replace(&mut *state, None);
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// If 'None', already failing and we've already gotten a kill signal.
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if newstate.is_some() {
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let group = option::unwrap(newstate);
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taskset_remove(if is_member { &mut group.members }
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else { &mut group.descendants }, me);
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*state = Some(group);
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}
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}
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// NB: Runs in destructor/post-exit context. Can't 'fail'.
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fn kill_taskgroup(state: TaskGroupInner, me: *rust_task, is_main: bool) {
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unsafe {
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// NB: We could do the killing iteration outside of the group arc, by
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// having "let mut newstate" here, swapping inside, and iterating
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// after. But that would let other exiting tasks fall-through and exit
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// while we were trying to kill them, causing potential
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// use-after-free. A task's presence in the arc guarantees it's alive
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// only while we hold the lock, so if we're failing, all concurrently
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// exiting tasks must wait for us. To do it differently, we'd have to
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// use the runtime's task refcounting, but that could leave task
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// structs around long after their task exited.
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let newstate = util::replace(state, None);
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// Might already be None, if Somebody is failing simultaneously.
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// That's ok; only one task needs to do the dirty work. (Might also
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// see 'None' if Somebody already failed and we got a kill signal.)
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if newstate.is_some() {
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let group = option::unwrap(newstate);
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for taskset_each(&group.members) |sibling| {
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// Skip self - killing ourself won't do much good.
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if sibling != me {
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rt::rust_task_kill_other(sibling);
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}
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}
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for taskset_each(&group.descendants) |child| {
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assert child != me;
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rt::rust_task_kill_other(child);
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}
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// Only one task should ever do this.
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if is_main {
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rt::rust_task_kill_all(me);
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}
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// Do NOT restore state to Some(..)! It stays None to indicate
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// that the whole taskgroup is failing, to forbid new spawns.
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}
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// (note: multiple tasks may reach this point)
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}
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}
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// FIXME (#2912): Work around core-vs-coretest function duplication. Can't use
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// a proper closure because the #[test]s won't understand. Have to fake it.
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macro_rules! taskgroup_key (
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// Use a "code pointer" value that will never be a real code pointer.
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() => (cast::transmute((-2 as uint, 0u)))
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)
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fn gen_child_taskgroup(linked: bool, supervised: bool)
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-> (TaskGroupArc, AncestorList, bool) {
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unsafe {
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let spawner = rt::rust_get_task();
|
|
/*##################################################################*
|
|
* Step 1. Get spawner's taskgroup info.
|
|
*##################################################################*/
|
|
let spawner_group = match local_get(spawner, taskgroup_key!()) {
|
|
None => {
|
|
// Main task, doing first spawn ever. Lazily initialise here.
|
|
let mut members = new_taskset();
|
|
taskset_insert(&mut members, spawner);
|
|
let tasks = unstable::exclusive(Some(TaskGroupData {
|
|
members: members,
|
|
descendants: new_taskset(),
|
|
}));
|
|
// Main task/group has no ancestors, no notifier, etc.
|
|
let group =
|
|
@TCB(spawner, tasks, AncestorList(None), true, None);
|
|
local_set(spawner, taskgroup_key!(), group);
|
|
group
|
|
}
|
|
Some(group) => group
|
|
};
|
|
/*##################################################################*
|
|
* Step 2. Process spawn options for child.
|
|
*##################################################################*/
|
|
return if linked {
|
|
// Child is in the same group as spawner.
|
|
let g = spawner_group.tasks.clone();
|
|
// Child's ancestors are spawner's ancestors.
|
|
let a = share_ancestors(&mut spawner_group.ancestors);
|
|
// Propagate main-ness.
|
|
(g, a, spawner_group.is_main)
|
|
} else {
|
|
// Child is in a separate group from spawner.
|
|
let g = unstable::exclusive(Some(TaskGroupData {
|
|
members: new_taskset(),
|
|
descendants: new_taskset(),
|
|
}));
|
|
let a = if supervised {
|
|
// Child's ancestors start with the spawner.
|
|
let old_ancestors =
|
|
share_ancestors(&mut spawner_group.ancestors);
|
|
// FIXME(#3068) - The generation counter is only used for a
|
|
// debug assertion, but initialising it requires locking a
|
|
// mutex. Hence it should be enabled only in debug builds.
|
|
let new_generation =
|
|
match *old_ancestors {
|
|
Some(ref arc) => {
|
|
access_ancestors(arc, |a| a.generation+1)
|
|
}
|
|
None => 0 // the actual value doesn't really matter.
|
|
};
|
|
assert new_generation < uint::max_value;
|
|
// Build a new node in the ancestor list.
|
|
AncestorList(Some(unstable::exclusive(AncestorNode {
|
|
generation: new_generation,
|
|
parent_group: Some(spawner_group.tasks.clone()),
|
|
ancestors: old_ancestors,
|
|
})))
|
|
} else {
|
|
// Child has no ancestors.
|
|
AncestorList(None)
|
|
};
|
|
(g, a, false)
|
|
};
|
|
}
|
|
|
|
fn share_ancestors(ancestors: &mut AncestorList) -> AncestorList {
|
|
// Appease the borrow-checker. Really this wants to be written as:
|
|
// match ancestors
|
|
// Some(ancestor_arc) { ancestor_list(Some(ancestor_arc.clone())) }
|
|
// None { ancestor_list(None) }
|
|
let tmp = util::replace(&mut **ancestors, None);
|
|
if tmp.is_some() {
|
|
let ancestor_arc = option::unwrap(tmp);
|
|
let result = ancestor_arc.clone();
|
|
**ancestors = Some(ancestor_arc);
|
|
AncestorList(Some(result))
|
|
} else {
|
|
AncestorList(None)
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn spawn_raw(opts: TaskOpts, f: ~fn()) {
|
|
let (child_tg, ancestors, is_main) =
|
|
gen_child_taskgroup(opts.linked, opts.supervised);
|
|
|
|
unsafe {
|
|
let child_data = Cell((child_tg, ancestors, f));
|
|
// Being killed with the unsafe task/closure pointers would leak them.
|
|
do unkillable {
|
|
// Agh. Get move-mode items into the closure. FIXME (#2829)
|
|
let (child_tg, ancestors, f) = child_data.take();
|
|
// Create child task.
|
|
let new_task = match opts.sched.mode {
|
|
DefaultScheduler => rt::new_task(),
|
|
_ => new_task_in_sched(opts.sched)
|
|
};
|
|
assert !new_task.is_null();
|
|
// Getting killed after here would leak the task.
|
|
let mut notify_chan = if opts.notify_chan.is_none() {
|
|
None
|
|
} else {
|
|
Some(option::swap_unwrap(&mut opts.notify_chan))
|
|
};
|
|
|
|
let child_wrapper = make_child_wrapper(new_task, child_tg,
|
|
ancestors, is_main, notify_chan, f);
|
|
|
|
let closure = cast::transmute(&child_wrapper);
|
|
|
|
// Getting killed between these two calls would free the child's
|
|
// closure. (Reordering them wouldn't help - then getting killed
|
|
// between them would leak.)
|
|
rt::start_task(new_task, closure);
|
|
cast::forget(child_wrapper);
|
|
}
|
|
}
|
|
|
|
// This function returns a closure-wrapper that we pass to the child task.
|
|
// (1) It sets up the notification channel.
|
|
// (2) It attempts to enlist in the child's group and all ancestor groups.
|
|
// (3a) If any of those fails, it leaves all groups, and does nothing.
|
|
// (3b) Otherwise it builds a task control structure and puts it in TLS,
|
|
// (4) ...and runs the provided body function.
|
|
fn make_child_wrapper(child: *rust_task, child_arc: TaskGroupArc,
|
|
ancestors: AncestorList, is_main: bool,
|
|
notify_chan: Option<Chan<TaskResult>>,
|
|
f: ~fn())
|
|
-> ~fn() {
|
|
let child_data = Cell((child_arc, ancestors));
|
|
let result: ~fn() = || {
|
|
// Agh. Get move-mode items into the closure. FIXME (#2829)
|
|
let mut (child_arc, ancestors) = child_data.take();
|
|
// Child task runs this code.
|
|
|
|
// Even if the below code fails to kick the child off, we must
|
|
// send Something on the notify channel.
|
|
|
|
//let mut notifier = None;//notify_chan.map(|c| AutoNotify(c));
|
|
let notifier = match notify_chan {
|
|
Some(ref notify_chan_value) => {
|
|
let moved_ncv = move_it!(*notify_chan_value);
|
|
Some(AutoNotify(moved_ncv))
|
|
}
|
|
_ => None
|
|
};
|
|
|
|
if enlist_many(child, &child_arc, &mut ancestors) {
|
|
let group = @TCB(child, child_arc, ancestors,
|
|
is_main, notifier);
|
|
unsafe {
|
|
local_set(child, taskgroup_key!(), group);
|
|
}
|
|
|
|
// Run the child's body.
|
|
f();
|
|
|
|
// TLS cleanup code will exit the taskgroup.
|
|
}
|
|
|
|
// Run the box annihilator.
|
|
// FIXME #4428: Crashy.
|
|
// unsafe { cleanup::annihilate(); }
|
|
};
|
|
return result;
|
|
|
|
// Set up membership in taskgroup and descendantship in all ancestor
|
|
// groups. If any enlistment fails, Some task was already failing, so
|
|
// don't let the child task run, and undo every successful enlistment.
|
|
fn enlist_many(child: *rust_task, child_arc: &TaskGroupArc,
|
|
ancestors: &mut AncestorList) -> bool {
|
|
// Join this taskgroup.
|
|
let mut result =
|
|
do access_group(child_arc) |child_tg| {
|
|
enlist_in_taskgroup(child_tg, child, true) // member
|
|
};
|
|
if result {
|
|
// Unwinding function in case any ancestral enlisting fails
|
|
let bail: @fn(TaskGroupInner) = |tg| {
|
|
leave_taskgroup(tg, child, false)
|
|
};
|
|
// Attempt to join every ancestor group.
|
|
result =
|
|
for each_ancestor(ancestors, Some(bail)) |ancestor_tg| {
|
|
// Enlist as a descendant, not as an actual member.
|
|
// Descendants don't kill ancestor groups on failure.
|
|
if !enlist_in_taskgroup(ancestor_tg, child, false) {
|
|
break;
|
|
}
|
|
};
|
|
// If any ancestor group fails, need to exit this group too.
|
|
if !result {
|
|
do access_group(child_arc) |child_tg| {
|
|
leave_taskgroup(child_tg, child, true); // member
|
|
}
|
|
}
|
|
}
|
|
result
|
|
}
|
|
}
|
|
|
|
fn new_task_in_sched(opts: SchedOpts) -> *rust_task {
|
|
if opts.foreign_stack_size != None {
|
|
fail!(~"foreign_stack_size scheduler option unimplemented");
|
|
}
|
|
|
|
let num_threads = match opts.mode {
|
|
DefaultScheduler
|
|
| CurrentScheduler
|
|
| ExistingScheduler(*)
|
|
| PlatformThread => 0u, /* Won't be used */
|
|
SingleThreaded => 1u,
|
|
ThreadPerCore => unsafe { rt::rust_num_threads() },
|
|
ThreadPerTask => {
|
|
fail!(~"ThreadPerTask scheduling mode unimplemented")
|
|
}
|
|
ManualThreads(threads) => {
|
|
if threads == 0u {
|
|
fail!(~"can not create a scheduler with no threads");
|
|
}
|
|
threads
|
|
}
|
|
};
|
|
|
|
unsafe {
|
|
let sched_id = match opts.mode {
|
|
CurrentScheduler => rt::rust_get_sched_id(),
|
|
ExistingScheduler(SchedulerHandle(id)) => id,
|
|
PlatformThread => rt::rust_osmain_sched_id(),
|
|
_ => rt::rust_new_sched(num_threads)
|
|
};
|
|
rt::rust_new_task_in_sched(sched_id)
|
|
}
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_spawn_raw_simple() {
|
|
let (po, ch) = stream();
|
|
do spawn_raw(default_task_opts()) {
|
|
ch.send(());
|
|
}
|
|
po.recv();
|
|
}
|
|
|
|
#[test]
|
|
#[ignore(cfg(windows))]
|
|
fn test_spawn_raw_unsupervise() {
|
|
let opts = task::TaskOpts {
|
|
linked: false,
|
|
notify_chan: None,
|
|
.. default_task_opts()
|
|
};
|
|
do spawn_raw(opts) {
|
|
fail!();
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
#[ignore(cfg(windows))]
|
|
fn test_spawn_raw_notify_success() {
|
|
let (notify_po, notify_ch) = comm::stream();
|
|
|
|
let opts = task::TaskOpts {
|
|
notify_chan: Some(notify_ch),
|
|
.. default_task_opts()
|
|
};
|
|
do spawn_raw(opts) {
|
|
}
|
|
assert notify_po.recv() == Success;
|
|
}
|
|
|
|
#[test]
|
|
#[ignore(cfg(windows))]
|
|
fn test_spawn_raw_notify_failure() {
|
|
// New bindings for these
|
|
let (notify_po, notify_ch) = comm::stream();
|
|
|
|
let opts = task::TaskOpts {
|
|
linked: false,
|
|
notify_chan: Some(notify_ch),
|
|
.. default_task_opts()
|
|
};
|
|
do spawn_raw(opts) {
|
|
fail!();
|
|
}
|
|
assert notify_po.recv() == Failure;
|
|
}
|