NaCl: Make thread exit wake pthread_join.

1 files changed, 45 insertions, 0 deletions

diff --git a/sysdeps/nacl/lowlevellock.h b/sysdeps/nacl/lowlevellock.h
new file mode 100644
index 0000000000..0b85d8d317
--- /dev/null
+++ b/sysdeps/nacl/lowlevellock.h
@@ -0,0 +1,45 @@
+/* Low-level lock implementation.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _LOWLEVELLOCK_H
+
+/* Everything except the exit handling is the same as the generic code.  */
+# include <sysdeps/nptl/lowlevellock.h>
+
+# ifndef BUSY_WAIT_NOP
+#  define BUSY_WAIT_NOP		__sync_synchronize ()
+# endif
+
+/* See exit-thread.h for details.  */
+# define NACL_EXITING_TID	1
+
+# undef lll_wait_tid
+# define lll_wait_tid(tid)				\
+  do {							\
+    __typeof (tid) __tid;				\
+    volatile __typeof (tid) *__tidp = &(tid);		\
+    while ((__tid = atomic_load_relaxed (__tidp)) != 0) \
+      {							\
+	if (__tid == NACL_EXITING_TID)			\
+	  BUSY_WAIT_NOP;				\
+	else						\
+	  lll_futex_wait (__tidp, __tid, LLL_PRIVATE);	\
+      }							\
+  } while (0)
+
+#endif	/* lowlevellock.h */