This patch to libgo uses Entersyscall and Exitsyscall when reading directory entries. This matters when reading a directory from something that can stall, such as NFS or a user-mounted file system. Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu. Committed to mainline.
Ian
diff -r 4700079bacc2 libgo/go/os/dir.go --- a/libgo/go/os/dir.go Tue Jun 12 13:32:45 2012 -0700 +++ b/libgo/go/os/dir.go Tue Jun 12 21:45:10 2012 -0700 @@ -42,7 +42,11 @@ if file.dirinfo == nil { file.dirinfo = new(dirInfo) file.dirinfo.buf = make([]byte, elen) - file.dirinfo.dir = libc_opendir(syscall.StringBytePtr(file.name)) + p := syscall.StringBytePtr(file.name) + syscall.Entersyscall() + r := libc_opendir(p) + syscall.Exitsyscall() + file.dirinfo.dir = r } entry_dirent := unsafe.Pointer(&file.dirinfo.buf[0]).(*syscall.Dirent) @@ -62,7 +66,10 @@ for n != 0 { var result *syscall.Dirent - i := libc_readdir_r(dir, entry_dirent, &result) + pr := &result + syscall.Entersyscall() + i := libc_readdir_r(dir, entry_dirent, pr) + syscall.Exitsyscall() if i != 0 { return names, NewSyscallError("readdir_r", i) }