internal/poll: fix the intermittent build failures with pipe pool

Correlative CL 308089

Fixes #45059

Change-Id: I1ff9fbf64e6620d651f287ba2a28d40f964d78a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/308329
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>

diff --git a/src/internal/poll/splice_linux_test.go b/src/internal/poll/splice_linux_test.go
index 9ea5197242a7f4cadadbd974b7c88faef421b621..77ae912d54319d79c1644885ba4ce37d89f308e2 100644 (file)
--- a/src/internal/poll/splice_linux_test.go
+++ b/src/internal/poll/splice_linux_test.go
@@ -6,6 +6,7 @@ package poll_test
 
 import (
        "internal/poll"
+       "internal/syscall/unix"
        "runtime"
        "syscall"
        "testing"
@@ -16,8 +17,8 @@ import (
 func checkPipes(fds []int) bool {
        for _, fd := range fds {
                // Check if each pipe fd has been closed.
-               err := syscall.FcntlFlock(uintptr(fd), syscall.F_GETFD, nil)
-               if err == nil {
+               _, _, errno := syscall.Syscall(unix.FcntlSyscall, uintptr(fd), syscall.F_GETPIPE_SZ, 0)
+               if errno == 0 {
                        return false
                }
        }
@@ -37,8 +38,8 @@ func TestSplicePipePool(t *testing.T) {
                if err != nil {
                        t.Skip("failed to create pipe, skip this test")
                }
-               prfd, pwfd := poll.GetPipeFds(p)
-               fds = append(fds, prfd, pwfd)
+               _, pwfd := poll.GetPipeFds(p)
+               fds = append(fds, pwfd)
                ps = append(ps, p)
        }
        for _, p = range ps {
@@ -46,19 +47,28 @@ func TestSplicePipePool(t *testing.T) {
        }
        ps = nil
 
-       var ok bool
-       // Trigger garbage collection to free the pipes in sync.Pool and check whether or not
-       // those pipe buffers have been closed as we expected.
-       for i := 0; i < 5; i++ {
+       // Exploit the timeout of "go test" as a timer for the subsequent verification.
+       timeout := 5 * time.Minute
+       if deadline, ok := t.Deadline(); ok {
+               timeout = deadline.Sub(time.Now())
+               timeout -= timeout / 10 // Leave 10% headroom for cleanup.
+       }
+       expiredTime := time.NewTimer(timeout)
+       defer expiredTime.Stop()
+
+       // Trigger garbage collection repeatedly, waiting for all pipes in sync.Pool
+       // to either be deallocated and closed, or to time out.
+       for {
                runtime.GC()
-               time.Sleep(time.Duration(i*100+10) * time.Millisecond)
-               if ok = checkPipes(fds); ok {
+               time.Sleep(10 * time.Millisecond)
+               if checkPipes(fds) {
                        break
                }
-       }
-
-       if !ok {
-               t.Fatal("at least one pipe is still open")
+               select {
+               case <-expiredTime.C:
+                       t.Fatal("at least one pipe is still open")
+               default:
+               }
        }
 }