do umtx_wake at userland thread exit address, so that others userland

threads can wait for a thread to exit, and safely assume that the thread
has left userland and is no longer using its userland stack, this is
necessary for pthread_join when a thread is waiting for another thread
to exit which has user customized stack, after pthread_join returns,
the userland stack can be reused for other purposes, without this change,
the joiner thread has to spin at the address to ensure the thread is really
exited.

1 files changed, 3 insertions, 3 deletions

diff --git a/sys/kern/kern_umtx.c b/sys/kern/kern_umtx.c
index c159487..9c8049e 100644
--- a/sys/kern/kern_umtx.c
+++ b/sys/kern/kern_umtx.c
@@ -687,8 +687,8 @@ out:
 	return (error);
 }
 
-static int
-do_wake(struct thread *td, void *uaddr, int n_wake)
+int
+kern_umtx_wake(struct thread *td, void *uaddr, int n_wake)
 {
 	struct umtx_key key;
 	int ret;
@@ -762,7 +762,7 @@ _umtx_op(struct thread *td, struct _umtx_op_args *uap)
 		error = do_wait(td, uap->umtx, uap->id, ts);
 		break;
 	case UMTX_OP_WAKE:
-		error = do_wake(td, uap->umtx, uap->id);
+		error = kern_umtx_wake(td, uap->umtx, uap->id);
 		break;
 	default:
 		error = EINVAL;