Consolidate non cancellable pause call

This patch consolidates all the non cancellable pause calls to use
the __pause_nocancel identifier.  For non cancellable targets it will
be just a macro to call the default respective symbol while on Linux
will be a internal one.

Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu.

	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full): Replace
	pause_not_cancel with __pause_nocancel.
	* sysdeps/generic/not-cancel.h (pause_not_cancel): Remove macro.
	(__pause_nocancel): New macro.
	* sysdeps/unix/sysv/linux/not-cancel.h (pause_not_cancel): Remove
	macro.
	(__pause_nocancel): New prototype.
	* sysdeps/unix/sysv/linux/pause.c (__pause_nocancel): New function.

ChangeLog

@@ -1,3 +1,14 @@
+2017-08-22  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
+
+	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full): Replace
+	pause_not_cancel with __pause_nocancel.
+	* sysdeps/generic/not-cancel.h (pause_not_cancel): Remove macro.
+	(__pause_nocancel): New macro.
+	* sysdeps/unix/sysv/linux/not-cancel.h (pause_not_cancel): Remove
+	macro.
+	(__pause_nocancel): New prototype.
+	* sysdeps/unix/sysv/linux/pause.c (__pause_nocancel): New function.
+
 2017-08-22  Martin Sebor  <msebor@redhat.com>
 
 	* include/libc-symbols.h (__ifunc_resolver): Declare resolver

include/unistd.h

@@ -172,8 +172,6 @@ extern __pid_t __libc_fork (void);
 /* Suspend the process until a signal arrives.
    This always returns -1 and sets `errno' to EINTR.  */
 extern int __libc_pause (void);
-/* Not cancelable variant.  */
-extern int __pause_nocancel (void) attribute_hidden;
 
 extern int __getlogin_r_loginuid (char *name, size_t namesize)
      attribute_hidden;

nptl/pthread_mutex_lock.c

@@ -428,7 +428,7 @@ __pthread_mutex_lock_full (pthread_mutex_t *mutex)
 
 		/* Delay the thread indefinitely.  */
 		while (1)
-		  pause_not_cancel ();
+		  __pause_nocancel ();
 	      }
 
 	    oldval = mutex->__data.__lock;

sysdeps/generic/not-cancel.h

@@ -38,7 +38,7 @@
   (void) __writev (fd, iov, n)
 # define __waitpid_nocancel(pid, stat_loc, options) \
   __waitpid (pid, stat_loc, options)
-#define pause_not_cancel() \
+#define __pause_nocancel() \
   __pause ()
 #define nanosleep_not_cancel(requested_time, remaining) \
   __nanosleep (requested_time, remaining)

sysdeps/posix/pause.c

@@ -39,18 +39,3 @@ __libc_pause (void)
 weak_alias (__libc_pause, pause)
 
 LIBC_CANCEL_HANDLED ();		/* sigsuspend handles our cancellation.  */
-
-#ifndef NO_CANCELLATION
-# include <not-cancel.h>
-
-int
-__pause_nocancel (void)
-{
-  sigset_t set;
-
-  __sigemptyset (&set);
-  __sigprocmask (SIG_BLOCK, NULL, &set);
-
-  return sigsuspend_not_cancel (&set);
-}
-#endif

sysdeps/unix/sysv/linux/not-cancel.h

@@ -77,14 +77,8 @@ __typeof (waitpid) __waitpid_nocancel;
 libc_hidden_proto (__waitpid_nocancel)
 
 /* Uncancelable pause.  */
-#define pause_not_cancel() \
-  ({ sigset_t set; 							     \
-     int __rc = INLINE_SYSCALL (rt_sigprocmask, 4, SIG_BLOCK, NULL, &set,    \
-				_NSIG / 8);				     \
-     if (__rc == 0)							     \
-       __rc = INLINE_SYSCALL (rt_sigsuspend, 2, &set, _NSIG / 8);	     \
-     __rc;								     \
-  })
+__typeof (pause) __pause_nocancel;
+libc_hidden_proto (__pause_nocancel)
 
 /* Uncancelable nanosleep.  */
 #define nanosleep_not_cancel(requested_time, remaining) \

sysdeps/unix/sysv/linux/pause.c

@@ -19,10 +19,10 @@
 #include <signal.h>
 #include <unistd.h>
 #include <sysdep-cancel.h>
+#include <not-cancel.h>
 
 /* Suspend the process until a signal arrives.
    This always returns -1 and sets errno to EINTR.  */
-
 int
 __libc_pause (void)
 {
@@ -33,3 +33,14 @@ __libc_pause (void)
 #endif
 }
 weak_alias (__libc_pause, pause)
+
+int
+__pause_nocancel (void)
+{
+#ifdef __NR_pause
+  return INLINE_SYSCALL_CALL (pause);
+#else
+  return INLINE_SYSCALL_CALL (ppoll, NULL, 0, NULL, NULL);
+#endif
+}
+libc_hidden_def (__pause_nocancel)