| // Copyright 2015 Colin Sherratt |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| extern crate atom; |
| |
| use atom::*; |
| use std::mem; |
| use std::sync::{Arc, Barrier}; |
| use std::thread; |
| |
| const THREADS: usize = 100; |
| |
| #[derive(Debug)] |
| struct Link { |
| next: AtomSetOnce<Box<Link>>, |
| } |
| |
| impl Drop for Link { |
| fn drop(&mut self) { |
| // This is done to avoid a recusive drop of the List |
| while let Some(mut h) = self.next.atom().take() { |
| self.next = mem::replace(&mut h.next, AtomSetOnce::empty()); |
| } |
| } |
| } |
| |
| fn main() { |
| let b = Arc::new(Barrier::new(THREADS + 1)); |
| |
| let head = Arc::new(Link { |
| next: AtomSetOnce::empty(), |
| }); |
| |
| for _ in 0..THREADS { |
| let b = b.clone(); |
| let head = head.clone(); |
| thread::spawn(move || { |
| let mut hptr = &*head; |
| |
| for _ in 0..10_000 { |
| let mut my_awesome_node = Box::new(Link { |
| next: AtomSetOnce::empty(), |
| }); |
| |
| loop { |
| while let Some(h) = hptr.next.get() { |
| hptr = h; |
| } |
| |
| my_awesome_node = match hptr.next.set_if_none(my_awesome_node) { |
| Some(v) => v, |
| None => break, |
| }; |
| } |
| } |
| b.wait(); |
| }); |
| } |
| |
| b.wait(); |
| |
| let mut hptr = &*head; |
| let mut count = 0; |
| while let Some(h) = hptr.next.get() { |
| hptr = h; |
| count += 1; |
| } |
| println!( |
| "Using {} threads we wrote {} links at the same time!", |
| THREADS, count |
| ); |
| } |