librt additions that are now possible with nptl

 * clock_getcpuclockid, clock_gettime, clock_nanosleep, mq_receive,
   mq_send, mq_timedreceive, mq_timedsend, _SC_MONOTONIC_CLOCK

Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

10 files changed, 613 insertions, 52 deletions

diff --git a/librt/Makefile.in b/librt/Makefile.in
index aaa19185a..ea1d03eb8 100644
--- a/librt/Makefile.in
+++ b/librt/Makefile.in
@@ -9,7 +9,12 @@ subdirs += librt
 
 CFLAGS-librt := -DNOT_IN_libc -DIS_IN_librt $(SSP_ALL_CFLAGS)
 
-LDFLAGS-librt.so := $(LDFLAGS) $(call link.asneeded,-lc)
+ifeq ($(UCLIBC_HAS_THREADS_NATIVE),y)
+LDFLAGS-librt.so := $(LDFLAGS) $(top_builddir)lib/libdl.so	\
+		    $(top_builddir)lib/libpthread.so
+else
+LDFLAGS-librt.so := $(LDFLAGS)
+endif
 
 LIBS-librt.so := $(LIBS)
 
@@ -19,22 +24,36 @@ librt_DIR := $(top_srcdir)librt
 librt_OUT := $(top_builddir)librt
 
 ifeq ($(UCLIBC_HAS_REALTIME),y)
-librt_SRC := $(wildcard $(librt_DIR)/*.c)
-librt_OBJ := $(patsubst $(librt_DIR)/%.c,$(librt_OUT)/%.o,$(librt_SRC))
+ifeq ($(UCLIBC_HAS_THREADS_NATIVE),y)
+librt_CSRC := $(filter-out mq_notify.c timer_create.c timer_delete.c	\
+	      timer_getoverr.c timer_gettime.c timer_settime.c,	\
+	      $(notdir $(wildcard $(librt_DIR)/*.c)))
+librt_SSRC := $(wildcard $(librt_DIR)/*.S)
+librt_OBJ := $(patsubst %.c,$(librt_OUT)/%.o,$(librt_CSRC))
+librt_OBJ += $(patsubst $(librt_DIR)/%.S,$(librt_OUT)/%.o,$(librt_SSRC))
+else
+librt_SRC := $(filter-out clock_nanosleep.c clock_getcpuclockid.c clock_gettime.c,	\
+	     $(notdir $(wildcard $(librt_DIR)/*.c)))
+librt_OBJ := $(patsubst %.c,$(librt_OUT)/%.o,$(librt_SRC))
+endif
+
+ASFLAGS-mq_timedreceive.S = -D_LIBC_REENTRANT
+ASFLAGS-mq_timedsend.S = -D_LIBC_REENTRANT
 
 ifeq ($(DOPIC),y)
 librt-a-y += $(librt_OBJ:.o=.os)
 else
 librt-a-y += $(librt_OBJ)
 endif
-librt-so-y += $(librt_OBJ:.o=.os)
+librt-so-y += $(librt_OBJ:.o=.oS)
 
 lib-a-y += $(top_builddir)lib/librt.a
 lib-so-y += $(top_builddir)lib/librt.so
 endif
 
-ifeq ($(DOPIC),y)
-$(top_builddir)lib/librt.so: $(top_builddir)lib/librt.a $(libc.depend)
+
+ifeq ($(DOPIC)$(UCLIBC_HAS_THREADS_NATIVE),yn)
+$(top_builddir)lib/librt.so: $(top_builddir)lib/librt.a $(libc.dpend)
 else
 $(top_builddir)lib/librt.so: $(librt_OUT)/librt_so.a $(libc.depend)
 endif
diff --git a/librt/clock_getcpuclockid.c b/librt/clock_getcpuclockid.c
new file mode 100644
index 000000000..704c57402
--- /dev/null
+++ b/librt/clock_getcpuclockid.c
@@ -0,0 +1,104 @@
+/* clock_getcpuclockid -- Get a clockid_t for process CPU time.  Linux version.
+   Copyright (C) 2004, 2005 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <time.h>
+#include <sysdep.h>
+#include <unistd.h>
+#include <bits/kernel-features.h>
+#include "kernel-posix-cpu-timers.h"
+
+#ifndef HAS_CPUCLOCK
+# define HAS_CPUCLOCK 1
+#endif
+
+int
+clock_getcpuclockid (pid_t pid, clockid_t *clock_id)
+{
+#ifdef __NR_clock_getres
+  /* The clockid_t value is a simple computation from the PID.
+     But we do a clock_getres call to validate it.  */
+
+  const clockid_t pidclock = MAKE_PROCESS_CPUCLOCK (pid, CPUCLOCK_SCHED);
+
+# if !(__ASSUME_POSIX_CPU_TIMERS > 0)
+  extern int __libc_missing_posix_cpu_timers attribute_hidden;
+#  if !(__ASSUME_POSIX_TIMERS > 0)
+  extern int __libc_missing_posix_timers attribute_hidden;
+  if (__libc_missing_posix_timers && !__libc_missing_posix_cpu_timers)
+    __libc_missing_posix_cpu_timers = 1;
+#  endif
+  if (!__libc_missing_posix_cpu_timers)
+# endif
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      int r = INTERNAL_SYSCALL (clock_getres, err, 2, pidclock, NULL);
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+	{
+	  *clock_id = pidclock;
+	  return 0;
+	}
+
+# if !(__ASSUME_POSIX_TIMERS > 0)
+      if (INTERNAL_SYSCALL_ERRNO (r, err) == ENOSYS)
+	{
+	  /* The kernel doesn't support these calls at all.  */
+	  __libc_missing_posix_timers = 1;
+	  __libc_missing_posix_cpu_timers = 1;
+	}
+      else
+# endif
+	if (INTERNAL_SYSCALL_ERRNO (r, err) == EINVAL)
+	  {
+# if !(__ASSUME_POSIX_CPU_TIMERS > 0)
+	    if (pidclock == MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED)
+		|| INTERNAL_SYSCALL_ERROR_P (INTERNAL_SYSCALL
+					     (clock_getres, err, 2,
+					      MAKE_PROCESS_CPUCLOCK
+					      (0, CPUCLOCK_SCHED), NULL),
+					     err))
+	      /* The kernel doesn't support these clocks at all.  */
+	      __libc_missing_posix_cpu_timers = 1;
+	    else
+# endif
+	      /* The clock_getres system call checked the PID for us.  */
+	      return ESRCH;
+	  }
+	else
+	  return INTERNAL_SYSCALL_ERRNO (r, err);
+    }
+#endif
+
+  /* We don't allow any process ID but our own.  */
+  if (pid != 0 && pid != getpid ())
+    return EPERM;
+
+#ifdef CLOCK_PROCESS_CPUTIME_ID
+  if (HAS_CPUCLOCK)
+    {
+      /* Store the number.  */
+      *clock_id = CLOCK_PROCESS_CPUTIME_ID;
+
+      return 0;
+    }
+#endif
+
+  /* We don't have a timer for that.  */
+  return ENOENT;
+}
diff --git a/librt/clock_gettime.c b/librt/clock_gettime.c
new file mode 100644
index 000000000..8308329b2
--- /dev/null
+++ b/librt/clock_gettime.c
@@ -0,0 +1,301 @@
+/* clock_gettime -- Get current time from a POSIX clockid_t.  Linux version.
+   Copyright (C) 2003, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#include <errno.h>
+#include <time.h>
+#include "kernel-posix-cpu-timers.h"
+#include <bits/kernel-features.h>
+
+
+#define SYSCALL_GETTIME \
+  retval = INLINE_SYSCALL (clock_gettime, 2, clock_id, tp); \
+  break
+
+#ifdef __ASSUME_POSIX_TIMERS
+
+/* This means the REALTIME and MONOTONIC clock are definitely
+   supported in the kernel.  */
+# define SYSDEP_GETTIME							      \
+  SYSDEP_GETTIME_CPUTIME						      \
+  case CLOCK_REALTIME:							      \
+  case CLOCK_MONOTONIC:							      \
+    SYSCALL_GETTIME
+
+# define __libc_missing_posix_timers 0
+#elif defined __NR_clock_gettime
+/* Is the syscall known to exist?  */
+int __libc_missing_posix_timers attribute_hidden;
+
+static inline int
+maybe_syscall_gettime (clockid_t clock_id, struct timespec *tp)
+{
+  int e = EINVAL;
+
+  if (!__libc_missing_posix_timers)
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      int r = INTERNAL_SYSCALL (clock_gettime, err, 2, clock_id, tp);
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+	return 0;
+
+      e = INTERNAL_SYSCALL_ERRNO (r, err);
+      if (e == ENOSYS)
+	{
+	  __libc_missing_posix_timers = 1;
+	  e = EINVAL;
+	}
+    }
+
+  return e;
+}
+
+/* The REALTIME and MONOTONIC clock might be available.  Try the
+   syscall first.  */
+# define SYSDEP_GETTIME							      \
+  SYSDEP_GETTIME_CPUTIME						      \
+  case CLOCK_REALTIME:							      \
+  case CLOCK_MONOTONIC:							      \
+    retval = maybe_syscall_gettime (clock_id, tp);			      \
+    if (retval == 0)							      \
+      break;								      \
+    /* Fallback code.  */						      \
+    if (retval == EINVAL && clock_id == CLOCK_REALTIME)			      \
+      retval = realtime_gettime (tp);					      \
+    else 								      \
+      {									      \
+	__set_errno (retval);						      \
+	retval = -1;							      \
+      }									      \
+    break;
+#endif
+
+#ifdef __NR_clock_gettime
+/* We handled the REALTIME clock here.  */
+# define HANDLED_REALTIME	1
+# define HANDLED_CPUTIME	1
+
+# if __ASSUME_POSIX_CPU_TIMERS > 0
+
+#  define SYSDEP_GETTIME_CPU SYSCALL_GETTIME
+#  define SYSDEP_GETTIME_CPUTIME	/* Default catches them too.  */
+
+# else
+
+int __libc_missing_posix_cpu_timers attribute_hidden;
+
+static int
+maybe_syscall_gettime_cpu (clockid_t clock_id, struct timespec *tp)
+{
+  int e = EINVAL;
+
+  if (!__libc_missing_posix_cpu_timers)
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      int r = INTERNAL_SYSCALL (clock_gettime, err, 2, clock_id, tp);
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+	return 0;
+
+      e = INTERNAL_SYSCALL_ERRNO (r, err);
+# ifndef __ASSUME_POSIX_TIMERS
+      if (e == ENOSYS)
+	{
+	  __libc_missing_posix_timers = 1;
+	  __libc_missing_posix_cpu_timers = 1;
+	  e = EINVAL;
+	}
+      else
+# endif
+	{
+	  if (e == EINVAL)
+	    {
+	      /* Check whether the kernel supports CPU clocks at all.
+		 If not, record it for the future.  */
+	      r = INTERNAL_SYSCALL (clock_getres, err, 2,
+				    MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED),
+				    NULL);
+	      if (INTERNAL_SYSCALL_ERROR_P (r, err))
+		__libc_missing_posix_cpu_timers = 1;
+	    }
+	}
+    }
+
+  return e;
+}
+
+#  define SYSDEP_GETTIME_CPU						      \
+  retval = maybe_syscall_gettime_cpu (clock_id, tp);			      \
+  if (retval == 0)							      \
+    break;								      \
+  if (retval != EINVAL || !__libc_missing_posix_cpu_timers)		      \
+    {									      \
+      __set_errno (retval);						      \
+      retval = -1;							      \
+      break;								      \
+    }									      \
+  retval = -1 /* Otherwise continue on to the HP_TIMING version.  */;
+
+static inline int
+maybe_syscall_gettime_cputime (clockid_t clock_id, struct timespec *tp)
+{
+  return maybe_syscall_gettime_cpu
+    (clock_id == CLOCK_THREAD_CPUTIME_ID
+     ? MAKE_THREAD_CPUCLOCK (0, CPUCLOCK_SCHED)
+     : MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED),
+     tp);
+}
+
+#  define SYSDEP_GETTIME_CPUTIME					      \
+    case CLOCK_PROCESS_CPUTIME_ID:					      \
+    case CLOCK_THREAD_CPUTIME_ID:					      \
+      retval = maybe_syscall_gettime_cputime (clock_id, tp);		      \
+      if (retval == 0)							      \
+	break;								      \
+      if (retval != EINVAL || !__libc_missing_posix_cpu_timers)		      \
+	{								      \
+	  __set_errno (retval);						      \
+	  retval = -1;							      \
+	  break;							      \
+	}								      \
+      retval = hp_timing_gettime (clock_id, tp);			      \
+      break;
+#  if !HP_TIMING_AVAIL
+#   define hp_timing_gettime(clock_id, tp) (__set_errno (EINVAL), -1)
+#  endif
+
+# endif
+#endif
+
+#include <errno.h>
+#include <stdint.h>
+#include <time.h>
+#include <sys/time.h>
+#include <libc-internal.h>
+#include <ldsodefs.h>
+
+
+#if HP_TIMING_AVAIL
+/* Clock frequency of the processor.  We make it a 64-bit variable
+   because some jokers are already playing with processors with more
+   than 4GHz.  */
+static hp_timing_t freq;
+
+
+/* This function is defined in the thread library.  */
+extern int __pthread_clock_gettime (clockid_t clock_id, hp_timing_t freq,
+				    struct timespec *tp)
+     __attribute__ ((__weak__));
+
+static int
+hp_timing_gettime (clockid_t clock_id, struct timespec *tp)
+{
+  hp_timing_t tsc;
+
+  if (__builtin_expect (freq == 0, 0))
+    {
+      /* This can only happen if we haven't initialized the `freq'
+	 variable yet.  Do this now. We don't have to protect this
+	 code against multiple execution since all of them should
+	 lead to the same result.  */
+      freq = __get_clockfreq ();
+      if (__builtin_expect (freq == 0, 0))
+	/* Something went wrong.  */
+	return -1;
+    }
+
+  if (clock_id != CLOCK_PROCESS_CPUTIME_ID
+      && __pthread_clock_gettime != NULL)
+    return __pthread_clock_gettime (clock_id, freq, tp);
+
+  /* Get the current counter.  */
+  HP_TIMING_NOW (tsc);
+
+  /* Compute the offset since the start time of the process.  */
+  tsc -= GL(dl_cpuclock_offset);
+
+  /* Compute the seconds.  */
+  tp->tv_sec = tsc / freq;
+
+  /* And the nanoseconds.  This computation should be stable until
+     we get machines with about 16GHz frequency.  */
+  tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;
+
+  return 0;
+}
+#endif
+
+
+static inline int
+realtime_gettime (struct timespec *tp)
+{
+  struct timeval tv;
+  int retval = gettimeofday (&tv, NULL);
+  if (retval == 0)
+    /* Convert into `timespec'.  */
+    TIMEVAL_TO_TIMESPEC (&tv, tp);
+  return retval;
+}
+
+librt_hidden_proto (clock_gettime)
+/* Get current value of CLOCK and store it in TP.  */
+int
+clock_gettime (clockid_t clock_id, struct timespec *tp)
+{
+  int retval = -1;
+#ifndef HANDLED_REALTIME
+  struct timeval tv;
+#endif
+
+  switch (clock_id)
+    {
+#ifdef SYSDEP_GETTIME
+      SYSDEP_GETTIME;
+#endif
+
+#ifndef HANDLED_REALTIME
+    case CLOCK_REALTIME:
+      retval = gettimeofday (&tv, NULL);
+      if (retval == 0)
+	TIMEVAL_TO_TIMESPEC (&tv, tp);
+      break;
+#endif
+
+    default:
+#ifdef SYSDEP_GETTIME_CPU
+      SYSDEP_GETTIME_CPU;
+#endif
+#if HP_TIMING_AVAIL
+      if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
+	  == CLOCK_THREAD_CPUTIME_ID)
+	retval = hp_timing_gettime (clock_id, tp);
+      else
+#endif
+	__set_errno (EINVAL);
+      break;
+
+#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
+    case CLOCK_PROCESS_CPUTIME_ID:
+      retval = hp_timing_gettime (clock_id, tp);
+      break;
+#endif
+    }
+
+  return retval;
+}
+librt_hidden_def (clock_gettime)
diff --git a/librt/clock_nanosleep.c b/librt/clock_nanosleep.c
new file mode 100644
index 000000000..69e60087e
--- /dev/null
+++ b/librt/clock_nanosleep.c
@@ -0,0 +1,96 @@
+/* Copyright (C) 2003, 2004, 2005 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <time.h>
+#include <errno.h>
+
+#include <sysdep-cancel.h>
+#include <bits/kernel-features.h>
+#include "kernel-posix-cpu-timers.h"
+
+
+#ifdef __ASSUME_POSIX_TIMERS
+/* We can simply use the syscall.  The CPU clocks are not supported
+   with this function.  */
+int
+clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
+		 struct timespec *rem)
+{
+  INTERNAL_SYSCALL_DECL (err);
+  int r;
+
+  if (clock_id == CLOCK_THREAD_CPUTIME_ID)
+    return EINVAL;
+  if (clock_id == CLOCK_PROCESS_CPUTIME_ID)
+    clock_id = MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED);
+
+  if (SINGLE_THREAD_P)
+    r = INTERNAL_SYSCALL (clock_nanosleep, err, 4, clock_id, flags, req, rem);
+  else
+    {
+      int oldstate = LIBC_CANCEL_ASYNC ();
+
+      r = INTERNAL_SYSCALL (clock_nanosleep, err, 4, clock_id, flags, req,
+			    rem);
+
+      LIBC_CANCEL_RESET (oldstate);
+    }
+
+  return (INTERNAL_SYSCALL_ERROR_P (r, err)
+	  ? INTERNAL_SYSCALL_ERRNO (r, err) : 0);
+}
+
+#else
+# ifdef __NR_clock_nanosleep
+/* Is the syscall known to exist?  */
+extern int __libc_missing_posix_timers attribute_hidden;
+
+/* The REALTIME and MONOTONIC clock might be available.  Try the
+   syscall first.  */
+#  define SYSDEP_NANOSLEEP \
+  if (!__libc_missing_posix_timers)					      \
+    {									      \
+      clockid_t syscall_clockid;					      \
+      INTERNAL_SYSCALL_DECL (err);					      \
+									      \
+      if (clock_id == CLOCK_THREAD_CPUTIME_ID)				      \
+	return EINVAL;							      \
+      if (clock_id == CLOCK_PROCESS_CPUTIME_ID)				      \
+	syscall_clockid = MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED);	      \
+      else								      \
+	syscall_clockid = clock_id;					      \
+									      \
+      int oldstate = LIBC_CANCEL_ASYNC ();				      \
+									      \
+      int r = INTERNAL_SYSCALL (clock_nanosleep, err, 4,		      \
+				syscall_clockid, flags, req, rem);	      \
+									      \
+      LIBC_CANCEL_RESET (oldstate);					      \
+									      \
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))				      \
+	return 0;							      \
+									      \
+      if (INTERNAL_SYSCALL_ERRNO (r, err) != ENOSYS)			      \
+	return INTERNAL_SYSCALL_ERRNO (r, err);				      \
+									      \
+      __libc_missing_posix_timers = 1;					      \
+    }
+# endif
+
+# include <sysdeps/unix/clock_nanosleep.c>
+#endif
diff --git a/librt/kernel-posix-cpu-timers.h b/librt/kernel-posix-cpu-timers.h
new file mode 100644
index 000000000..164a90dde
--- /dev/null
+++ b/librt/kernel-posix-cpu-timers.h
@@ -0,0 +1,18 @@
+/* Parameters for the Linux kernel ABI for CPU clocks.  */
+
+#define CPUCLOCK_PID(clock)		((pid_t) ~((clock) >> 3))
+#define CPUCLOCK_PERTHREAD(clock) \
+	(((clock) & (clockid_t) CPUCLOCK_PERTHREAD_MASK) != 0)
+#define CPUCLOCK_PID_MASK	7
+#define CPUCLOCK_PERTHREAD_MASK	4
+#define CPUCLOCK_WHICH(clock)	((clock) & (clockid_t) CPUCLOCK_CLOCK_MASK)
+#define CPUCLOCK_CLOCK_MASK	3
+#define CPUCLOCK_PROF		0
+#define CPUCLOCK_VIRT		1
+#define CPUCLOCK_SCHED		2
+#define CPUCLOCK_MAX		3
+
+#define MAKE_PROCESS_CPUCLOCK(pid, clock) \
+	((~(clockid_t) (pid) << 3) | (clockid_t) (clock))
+#define MAKE_THREAD_CPUCLOCK(tid, clock) \
+	MAKE_PROCESS_CPUCLOCK((tid), (clock) | CPUCLOCK_PERTHREAD_MASK)
diff --git a/librt/kernel-posix-timers.h b/librt/kernel-posix-timers.h
index bf246c925..27d3f1fd7 100644
--- a/librt/kernel-posix-timers.h
+++ b/librt/kernel-posix-timers.h
@@ -10,6 +10,20 @@
 #include <pthread.h>
 #endif
 
+#ifdef __UCLIBC_HAS_THREADS_NATIVE__
+/* Nonzero if the system calls are not available.  */
+extern int __no_posix_timers attribute_hidden;
+
+/* Callback to start helper thread.  */
+extern void __start_helper_thread (void) attribute_hidden;
+
+/* Control variable for helper thread creation.  */
+extern pthread_once_t __helper_once attribute_hidden;
+
+/* TID of the helper thread.  */
+extern pid_t __helper_tid attribute_hidden;
+#endif
+
 /* Type of timers in the kernel */
 typedef int kernel_timer_t;
 
diff --git a/librt/mq_receive.c b/librt/mq_receive.c
index c0392b0f9..40447dfb9 100644
--- a/librt/mq_receive.c
+++ b/librt/mq_receive.c
@@ -6,13 +6,18 @@
 #include <stddef.h>
 #include <sys/syscall.h>
 #include <mqueue.h>
+#warning FIXME: hard dependency on ADVANCED REALTIME feature
 
+librt_hidden_proto(mq_timedreceive)
+
+#ifndef __UCLIBC_HAS_THREADS_NATIVE__
 #ifdef __NR_mq_timedreceive
 #define __NR___syscall_mq_timedreceive __NR_mq_timedreceive
-static _syscall5(int, __syscall_mq_timedreceive, int, mqdes,
-		 char *, msg_ptr, size_t, msg_len, unsigned int *,
-		 msg_prio, const void *, abs_timeout)
-# if defined __USE_XOPEN2K && defined __UCLIBC_HAS_ADVANCED_REALTIME__
+static __inline__ _syscall5(int, __syscall_mq_timedreceive, int, mqdes,
+			char *, msg_ptr, size_t, msg_len, unsigned int *,
+			msg_prio, const void *, abs_timeout);
+#endif
+
 /*
  * Receive the oldest from highest priority messages.
  * Stop waiting if abs_timeout expires.
@@ -21,31 +26,21 @@ ssize_t mq_timedreceive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
 			unsigned int *msg_prio,
 			const struct timespec *abs_timeout)
 {
+#ifdef __NR_mq_timedreceive
 	return __syscall_mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio,
 					 abs_timeout);
+#else
+	errno = ENOSYS;
+	return -1;
+#endif
 }
-# endif
+
+librt_hidden_def(mq_timedreceive)
+#endif
 
 /* Receive the oldest from highest priority messages */
 ssize_t mq_receive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
 		   unsigned int *msg_prio)
 {
-	return __syscall_mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio, NULL);
+	return mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio, NULL);
 }
-#elif defined __UCLIBC_HAS_STUBS__
-# if defined __USE_XOPEN2K && defined __UCLIBC_HAS_ADVANCED_REALTIME__
-ssize_t mq_timedreceive(mqd_t mqdes attribute_unused, char *msg_ptr attribute_unused,
-			size_t msg_len attribute_unused, unsigned int *msg_prio attribute_unused,
-			const struct timespec *abs_timeout attribute_unused)
-{
-	__set_errno(ENOSYS);
-	return -1;
-}
-# endif
-ssize_t mq_receive(mqd_t mqdes attribute_unused, char *msg_ptr attribute_unused,
-		   size_t msg_len attribute_unused, unsigned int *msg_prio attribute_unused)
-{
-	__set_errno(ENOSYS);
-	return -1;
-}
-#endif
diff --git a/librt/mq_send.c b/librt/mq_send.c
index 4c1a492b4..f0fcfa35a 100644
--- a/librt/mq_send.c
+++ b/librt/mq_send.c
@@ -6,14 +6,18 @@
 #include <stddef.h>
 #include <sys/syscall.h>
 #include <mqueue.h>
+#warning FIXME: hard dependency on ADVANCED REALTIME feature
 
+librt_hidden_proto(mq_timedsend)
+
+#ifndef __UCLIBC_HAS_THREADS_NATIVE__
 #ifdef __NR_mq_timedsend
 #define __NR___syscall_mq_timedsend __NR_mq_timedsend
-static _syscall5(int, __syscall_mq_timedsend, int, mqdes,
-		 const char *, msg_ptr, size_t, msg_len, unsigned int,
-		 msg_prio, const void *, abs_timeout);
+static __inline__ _syscall5(int, __syscall_mq_timedsend, int, mqdes,
+			const char *, msg_ptr, size_t, msg_len, unsigned int,
+			msg_prio, const void *, abs_timeout);
+#endif
 
-# if defined __USE_XOPEN2K && defined __UCLIBC_HAS_ADVANCED_REALTIME__
 /*
  * Add a message to queue. If O_NONBLOCK is set and queue is full, wait
  * for sufficient room in the queue until abs_timeout expires.
@@ -21,31 +25,21 @@ static _syscall5(int, __syscall_mq_timedsend, int, mqdes,
 int mq_timedsend(mqd_t mqdes, const char *msg_ptr, size_t msg_len,
 		 unsigned int msg_prio, const struct timespec *abs_timeout)
 {
+#ifdef __NR_mq_timedsend
 	return __syscall_mq_timedsend(mqdes, msg_ptr, msg_len, msg_prio,
 				      abs_timeout);
+#else
+	errno = ENOSYS;
+	return -1;
+#endif
 }
-# endif
+
+librt_hidden_def(mq_timedsend)
+#endif
 
 /* Add a message to queue */
 int mq_send(mqd_t mqdes, const char *msg_ptr, size_t msg_len,
 	    unsigned int msg_prio)
 {
-	return __syscall_mq_timedsend(mqdes, msg_ptr, msg_len, msg_prio, NULL);
+	return mq_timedsend(mqdes, msg_ptr, msg_len, msg_prio, NULL);
 }
-#elif defined __UCLIBC_HAS_STUBS__
-# if defined __USE_XOPEN2K && defined __UCLIBC_HAS_ADVANCED_REALTIME__
-int mq_timedsend(mqd_t mqdes attribute_unused, const char *msg_ptr attribute_unused,
-		 size_t msg_len attribute_unused, unsigned int msg_prio attribute_unused,
-		 const struct timespec *abs_timeout attribute_unused)
-{
-	__set_errno(ENOSYS);
-	return -1;
-}
-# endif
-int mq_send(mqd_t mqdes attribute_unused, const char *msg_ptr attribute_unused,
-	    size_t msg_len attribute_unused, unsigned int msg_prio attribute_unused)
-{
-	__set_errno(ENOSYS);
-	return -1;
-}
-#endif
diff --git a/librt/mq_timedreceive.S b/librt/mq_timedreceive.S
new file mode 100644
index 000000000..015eb8842
--- /dev/null
+++ b/librt/mq_timedreceive.S
@@ -0,0 +1,10 @@
+#include <sysdep-cancel.h>
+#ifndef __NR_mq_timedreceive
+#error Missing definition of NR_timedreceive needed for cancellation.
+#endif
+PSEUDO (__mq_timedreceive, mq_timedreceive, 5)
+ret
+PSEUDO_END(__mq_timedreceive)
+librt_hidden_def (__mq_timedreceive)
+weak_alias (__mq_timedreceive, mq_timedreceive)
+librt_hidden_weak (mq_timedreceive)
diff --git a/librt/mq_timedsend.S b/librt/mq_timedsend.S
new file mode 100644
index 000000000..67758a3b9
--- /dev/null
+++ b/librt/mq_timedsend.S
@@ -0,0 +1,10 @@
+#include <sysdep-cancel.h>
+#ifndef __NR_mq_timedsend
+#error Missing definition of NR_timedsend needed for cancellation.
+#endif
+PSEUDO (__mq_timedsend, mq_timedsend, 5)
+ret
+PSEUDO_END(__mq_timedsend)
+librt_hidden_def (__mq_timedsend)
+weak_alias (__mq_timedsend, mq_timedsend)
+librt_hidden_weak (mq_timedsend)