nptl: Cleanup cancellation macros

This patch wraps all uses of *_{enable,disable}_asynccancel and
and *_CANCEL_{ASYNC,RESET} in either already provided macros
(lll_futex_timed_wait_cancel) or creates new ones if the
functionality is not provided (SYSCALL_CANCEL_NCS, lll_futex_wait_cancel,
and lll_futex_timed_wait_cancel).

Also for some generic implementations, the direct call of the macros
are removed since the underlying symbols are suppose to provide
cancellation support.

This is a priliminary patch intended to simplify the work required
for BZ#12683 fix.  It is a refactor change, no semantic changes are
expected.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	* nptl/pthread_join_common.c (__pthread_timedjoin_ex): Use
	lll_wait_tid with timeout.
	* nptl/sem_wait.c (__old_sem_wait): Use lll_futex_wait_cancel.
	* sysdeps/nptl/aio_misc.h (AIO_MISC_WAIT): Use
	futex_reltimed_wait_cancelable for cancelabla mode.
	* sysdeps/nptl/gai_misc.h (GAI_MISC_WAIT): Likewise.
	* sysdeps/posix/open64.c (__libc_open64): Do not call cancelation
	macros.
	* sysdeps/posix/sigwait.c (__sigwait): Likewise.
	* sysdeps/posix/waitid.c (__sigwait): Likewise.
	* sysdeps/unix/sysdep.h (__SYSCALL_CANCEL_CALL,
	SYSCALL_CANCEL_NCS): New macro.
	* sysdeps/nptl/lowlevellock.h (lll_wait_tid): Add timeout argument.
	(lll_timedwait_tid): Remove macro.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/clock_nanosleep.c (__clock_nanosleep):
	Use INTERNAL_SYSCALL_CANCEL.
	* sysdeps/unix/sysv/linux/futex-internal.h
	(futex_reltimed_wait_cancelable): Use LIBC_CANCEL_{ASYNC,RESET}
	instead of __pthread_{enable,disable}_asynccancel.
	* sysdeps/unix/sysv/linux/lowlevellock-futex.h
	(lll_futex_wait_cancel): New macro.

1 files changed, 19 insertions, 21 deletions

diff --git a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h b/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
index e44a33f4c3..563b297655 100644
--- a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
+++ b/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
@@ -224,32 +224,30 @@ extern int __lll_timedlock_elision (int *futex, short *adapt_count,
 #define lll_islocked(futex) \
   (futex != LLL_LOCK_INITIALIZER)
 
+extern int __lll_timedwait_tid (int *, const struct timespec *)
+     attribute_hidden;
 
 /* The kernel notifies a process which uses CLONE_CHILD_CLEARTID via futex
    wake-up when the clone terminates.  The memory location contains the
    thread ID while the clone is running and is reset to zero by the kernel
    afterwards.  The kernel up to version 3.16.3 does not use the private futex
-   operations for futex wake-up when the clone terminates.  */
-#define lll_wait_tid(tid) \
-  do {					\
-    __typeof (tid) __tid;		\
-    while ((__tid = (tid)) != 0)	\
-      lll_futex_wait (&(tid), __tid, LLL_SHARED);\
-  } while (0)
-
-extern int __lll_timedwait_tid (int *, const struct timespec *)
-     attribute_hidden;
-
-/* As lll_wait_tid, but with a timeout.  If the timeout occurs then return
-   ETIMEDOUT.  If ABSTIME is invalid, return EINVAL.
-   XXX Note that this differs from the generic version in that we do the
-   error checking here and not in __lll_timedwait_tid.  */
-#define lll_timedwait_tid(tid, abstime) \
-  ({									      \
-    int __result = 0;							      \
-    if ((tid) != 0)							      \
-      __result = __lll_timedwait_tid (&(tid), (abstime));		      \
-    __result; })
+   operations for futex wake-up when the clone terminates.
+   If ABSTIME is not NULL, is used a timeout for futex call.  If the timeout
+   occurs then return ETIMEOUT, if ABSTIME is invalid, return EINVAL.
+   The futex operation are issues with cancellable versions.  */
+#define lll_wait_tid(tid, abstime)					\
+  ({									\
+    int __res = 0;							\
+    __typeof (tid) __tid;						\
+    if (abstime != NULL)						\
+      __res = __lll_timedwait_tid (&(tid), (abstime));			\
+    else								\
+      /* We need acquire MO here so that we synchronize with the 	\
+	 kernel's store to 0 when the clone terminates. (see above)  */	\
+      while ((__tid = atomic_load_acquire (&(tid))) != 0)		\
+        lll_futex_wait_cancel (&(tid), __tid, LLL_SHARED);		\
+    __res;								\
+  })
 
 extern int __lll_lock_elision (int *futex, short *adapt_count, int private)
   attribute_hidden;