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-rw-r--r--packages/Python/lldbsuite/test/lang/go/goroutines/main.go89
1 files changed, 89 insertions, 0 deletions
diff --git a/packages/Python/lldbsuite/test/lang/go/goroutines/main.go b/packages/Python/lldbsuite/test/lang/go/goroutines/main.go
new file mode 100644
index 000000000000..bb44f7b8b716
--- /dev/null
+++ b/packages/Python/lldbsuite/test/lang/go/goroutines/main.go
@@ -0,0 +1,89 @@
+package main
+
+import (
+ "fmt"
+ "runtime"
+)
+
+type philosopher struct {
+ i int
+ forks [2]chan bool
+ eating chan int
+ done chan struct{}
+}
+
+func (p philosopher) run() {
+ for {
+ select {
+ case <-p.done:
+ return
+ case <-p.forks[0]:
+ p.eat()
+ }
+ }
+}
+
+func (p philosopher) eat() {
+ select {
+ case <-p.done:
+ return
+ case <-p.forks[1]:
+ p.eating <- p.i
+ p.forks[0] <- true
+ p.forks[1] <- true
+ runtime.Gosched()
+ }
+}
+
+func startPhilosophers(n int) (chan struct{}, chan int) {
+ philosophers := make([]*philosopher, n)
+ chans := make([]chan bool, n)
+ for i := range chans {
+ chans[i] = make(chan bool, 1)
+ chans[i] <- true
+ }
+ eating := make(chan int, n)
+ done := make(chan struct{})
+ for i := range philosophers {
+ var min, max int
+ if i == n - 1 {
+ min = 0
+ max = i
+ } else {
+ min = i
+ max = i + 1
+ }
+ philosophers[i] = &philosopher{i: i, forks: [2]chan bool{chans[min], chans[max]}, eating: eating, done: done}
+ go philosophers[i].run()
+ }
+ return done, eating
+}
+
+func wait(c chan int) {
+ fmt.Println(<- c)
+ runtime.Gosched()
+}
+
+func main() {
+ // Restrict go to 1 real thread so we can be sure we're seeing goroutines
+ // and not threads.
+ runtime.GOMAXPROCS(1)
+ // Create a bunch of goroutines
+ done, eating := startPhilosophers(20) // stop1
+ // Now turn up the number of threads so this goroutine is likely to get
+ // scheduled on a different thread.
+ runtime.GOMAXPROCS(runtime.NumCPU()) // stop2
+ // Now let things run. Hopefully we'll bounce around
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ wait(eating)
+ close(done)
+ fmt.Println("done") // stop3
+}