diff --git a/manual/threads.texi b/manual/threads.texi
index 91462f5..83b8bb6 100644
--- a/manual/threads.texi
+++ b/manual/threads.texi
@@ -699,6 +699,34 @@ specified or defaulted when @code{pthread_cond_init} was called. Currently,
 @code{CLOCK_REALTIME}.
 @end deftypefun
 
+@comment pthread.h
+@comment POSIX-proposed
+@deftypefun int pthread_rwlock_clockrdlock (pthread_rwlock_t *@var{rwlock},
+				       clockid_t @var{clockid},
+				       const struct timespec *@var{abstime})
+
+@safety{@prelim{}@mtsafe{}@asunsafe{@asulock{}}@acunsafe{@aculock{}}}
+Behaves like @code{pthread_rwlock_timedrdlock} except the time
+@var{abstime} is measured against the clock specified by @var{clockid}
+rather than @code{CLOCK_REALTIME}. Currently, @var{clockid} must be either
+@code{CLOCK_MONOTONIC} or @code{CLOCK_REALTIME}, otherwise @code{EINVAL} is
+returned.
+@end deftypefun
+
+@comment pthread.h
+@comment POSIX-proposed
+@deftypefun int pthread_rwlock_clockwrlock (pthread_rwlock_t *@var{rwlock},
+				       clockid_t @var{clockid},
+				       const struct timespec *@var{abstime})
+
+@safety{@prelim{}@mtsafe{}@asunsafe{@asulock{}}@acunsafe{@aculock{}}}
+Behaves like @code{pthread_rwlock_timedwrlock} except the time
+@var{abstime} is measured against the clock specified by @var{clockid}
+rather than @code{CLOCK_REALTIME}. Currently, @var{clockid} must be either
+@code{CLOCK_MONOTONIC} or @code{CLOCK_REALTIME}, otherwise @code{EINVAL} is
+returned.
+@end deftypefun
+
 @c FIXME these are undocumented:
 @c pthread_atfork
 @c pthread_attr_destroy
diff --git a/nptl/Makefile b/nptl/Makefile
index 7de4d40..f5e6d90 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -76,7 +76,9 @@ libpthread-routines = nptl-init nptlfreeres vars events version pt-interp \
 		      pthread_mutexattr_gettype pthread_mutexattr_settype \
 		      pthread_rwlock_init pthread_rwlock_destroy \
 		      pthread_rwlock_rdlock pthread_rwlock_timedrdlock \
+		      pthread_rwlock_clockrdlock \
 		      pthread_rwlock_wrlock pthread_rwlock_timedwrlock \
+		      pthread_rwlock_clockwrlock \
 		      pthread_rwlock_tryrdlock pthread_rwlock_trywrlock \
 		      pthread_rwlock_unlock \
 		      pthread_rwlockattr_init pthread_rwlockattr_destroy \
diff --git a/nptl/Versions b/nptl/Versions
index 8c094d0..ce79959 100644
--- a/nptl/Versions
+++ b/nptl/Versions
@@ -279,6 +279,7 @@ libpthread {
 
   GLIBC_2.30 {
     sem_clockwait; pthread_cond_clockwait;
+    pthread_rwlock_clockrdlock; pthread_rwlock_clockwrlock;
   }
 
   GLIBC_PRIVATE {
diff --git a/nptl/pthread_rwlock_clockrdlock.c b/nptl/pthread_rwlock_clockrdlock.c
new file mode 100644
index 0000000..a6c7456
--- /dev/null
+++ b/nptl/pthread_rwlock_clockrdlock.c
@@ -0,0 +1,27 @@
+/* Copyright (C) 2019 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/>.  */
+
+#include "pthread_rwlock_common.c"
+
+/* See pthread_rwlock_common.c.  */
+int
+pthread_rwlock_clockrdlock (pthread_rwlock_t *rwlock,
+    clockid_t clockid,
+    const struct timespec *abstime)
+{
+  return __pthread_rwlock_rdlock_full (rwlock, clockid, abstime);
+}
diff --git a/nptl/pthread_rwlock_clockwrlock.c b/nptl/pthread_rwlock_clockwrlock.c
new file mode 100644
index 0000000..d248a2a
--- /dev/null
+++ b/nptl/pthread_rwlock_clockwrlock.c
@@ -0,0 +1,27 @@
+/* Copyright (C) 2019 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/>.  */
+
+#include "pthread_rwlock_common.c"
+
+/* See pthread_rwlock_common.c.  */
+int
+pthread_rwlock_clockwrlock (pthread_rwlock_t *rwlock,
+    clockid_t clockid,
+    const struct timespec *abstime)
+{
+  return __pthread_rwlock_wrlock_full (rwlock, clockid, abstime);
+}
diff --git a/nptl/pthread_rwlock_common.c b/nptl/pthread_rwlock_common.c
index 120b880..50a366e 100644
--- a/nptl/pthread_rwlock_common.c
+++ b/nptl/pthread_rwlock_common.c
@@ -278,17 +278,19 @@ __pthread_rwlock_rdunlock (pthread_rwlock_t *rwlock)
 
 static __always_inline int
 __pthread_rwlock_rdlock_full (pthread_rwlock_t *rwlock,
+    clockid_t clockid,
     const struct timespec *abstime)
 {
   unsigned int r;
 
-  /* Make sure any passed in timeout value is valid.  Note that the previous
-     implementation assumed that this check *must* not be performed if there
-     would in fact be no blocking; however, POSIX only requires that "the
-     validity of the abstime parameter need not be checked if the lock can be
-     immediately acquired" (i.e., we need not but may check it).  */
-  if (abstime
-      && __glibc_unlikely (abstime->tv_nsec >= 1000000000
+  /* Make sure any passed in clockid and timeout value are valid. Note
+     that the previous implementation assumed that this check *must*
+     not be performed if there would in fact be no blocking; however,
+     POSIX only requires that "the validity of the abstime parameter
+     need not be checked if the lock can be immediately acquired"
+     (i.e., we need not but may check it). */
+  if (abstime && __glibc_unlikely (!futex_abstimed_supported_clockid (clockid)
+      || abstime->tv_nsec >= 1000000000
       || abstime->tv_nsec < 0))
     return EINVAL;
 
@@ -329,7 +331,7 @@ __pthread_rwlock_rdlock_full (pthread_rwlock_t *rwlock,
 		{
 		  int private = __pthread_rwlock_get_private (rwlock);
 		  int err = futex_abstimed_wait (&rwlock->__data.__readers,
-						 r, CLOCK_REALTIME, abstime, private);
+						 r, clockid, abstime, private);
 		  /* We ignore EAGAIN and EINTR.  On time-outs, we can just
 		     return because we don't need to clean up anything.  */
 		  if (err == ETIMEDOUT)
@@ -457,7 +459,7 @@ __pthread_rwlock_rdlock_full (pthread_rwlock_t *rwlock,
 	    continue;
 	  int err = futex_abstimed_wait (&rwlock->__data.__wrphase_futex,
 					 1 | PTHREAD_RWLOCK_FUTEX_USED,
-					 CLOCK_REALTIME, abstime, private);
+					 clockid, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      /* If we timed out, we need to unregister.  If no read phase
@@ -584,15 +586,17 @@ __pthread_rwlock_wrunlock (pthread_rwlock_t *rwlock)
 
 static __always_inline int
 __pthread_rwlock_wrlock_full (pthread_rwlock_t *rwlock,
+    clockid_t clockid,
     const struct timespec *abstime)
 {
-  /* Make sure any passed in timeout value is valid.  Note that the previous
-     implementation assumed that this check *must* not be performed if there
-     would in fact be no blocking; however, POSIX only requires that "the
-     validity of the abstime parameter need not be checked if the lock can be
-     immediately acquired" (i.e., we need not but may check it).  */
-  if (abstime
-      && __glibc_unlikely (abstime->tv_nsec >= 1000000000
+  /* Make sure any passed in clockid and timeout value are valid. Note
+     that the previous implementation assumed that this check *must*
+     not be performed if there would in fact be no blocking; however,
+     POSIX only requires that "the validity of the abstime parameter
+     need not be checked if the lock can be immediately acquired"
+     (i.e., we need not but may check it). */
+  if (abstime && __glibc_unlikely (!futex_abstimed_supported_clockid (clockid)
+      || abstime->tv_nsec >= 1000000000
       || abstime->tv_nsec < 0))
     return EINVAL;
 
@@ -727,7 +731,7 @@ __pthread_rwlock_wrlock_full (pthread_rwlock_t *rwlock,
 	  may_share_futex_used_flag = true;
 	  int err = futex_abstimed_wait (&rwlock->__data.__writers_futex,
 					 1 | PTHREAD_RWLOCK_FUTEX_USED,
-					 CLOCK_REALTIME, abstime, private);
+					 clockid, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      if (prefer_writer)
@@ -826,7 +830,7 @@ __pthread_rwlock_wrlock_full (pthread_rwlock_t *rwlock,
 	    continue;
 	  int err = futex_abstimed_wait (&rwlock->__data.__wrphase_futex,
 					 PTHREAD_RWLOCK_FUTEX_USED,
-					 CLOCK_REALTIME, abstime, private);
+					 clockid, abstime, private);
 	  if (err == ETIMEDOUT)
 	    {
 	      if (rwlock->__data.__flags != PTHREAD_RWLOCK_PREFER_READER_NP)
diff --git a/nptl/pthread_rwlock_rdlock.c b/nptl/pthread_rwlock_rdlock.c
index 5fdc89e..387c824 100644
--- a/nptl/pthread_rwlock_rdlock.c
+++ b/nptl/pthread_rwlock_rdlock.c
@@ -24,7 +24,7 @@ __pthread_rwlock_rdlock (pthread_rwlock_t *rwlock)
 {
   LIBC_PROBE (rdlock_entry, 1, rwlock);
 
-  int result = __pthread_rwlock_rdlock_full (rwlock, NULL);
+  int result = __pthread_rwlock_rdlock_full (rwlock, CLOCK_REALTIME, NULL);
   LIBC_PROBE (rdlock_acquire_read, 1, rwlock);
   return result;
 }
diff --git a/nptl/pthread_rwlock_timedrdlock.c b/nptl/pthread_rwlock_timedrdlock.c
index 84c1983..8f8e680 100644
--- a/nptl/pthread_rwlock_timedrdlock.c
+++ b/nptl/pthread_rwlock_timedrdlock.c
@@ -23,5 +23,5 @@ int
 pthread_rwlock_timedrdlock (pthread_rwlock_t *rwlock,
     const struct timespec *abstime)
 {
-  return __pthread_rwlock_rdlock_full (rwlock, abstime);
+  return __pthread_rwlock_rdlock_full (rwlock, CLOCK_REALTIME, abstime);
 }
diff --git a/nptl/pthread_rwlock_timedwrlock.c b/nptl/pthread_rwlock_timedwrlock.c
index f0b745d..a5616de 100644
--- a/nptl/pthread_rwlock_timedwrlock.c
+++ b/nptl/pthread_rwlock_timedwrlock.c
@@ -23,5 +23,5 @@ int
 pthread_rwlock_timedwrlock (pthread_rwlock_t *rwlock,
     const struct timespec *abstime)
 {
-  return __pthread_rwlock_wrlock_full (rwlock, abstime);
+  return __pthread_rwlock_wrlock_full (rwlock, CLOCK_REALTIME, abstime);
 }
diff --git a/nptl/pthread_rwlock_wrlock.c b/nptl/pthread_rwlock_wrlock.c
index 194a14c..da246d8 100644
--- a/nptl/pthread_rwlock_wrlock.c
+++ b/nptl/pthread_rwlock_wrlock.c
@@ -24,7 +24,7 @@ __pthread_rwlock_wrlock (pthread_rwlock_t *rwlock)
 {
   LIBC_PROBE (wrlock_entry, 1, rwlock);
 
-  int result = __pthread_rwlock_wrlock_full (rwlock, NULL);
+  int result = __pthread_rwlock_wrlock_full (rwlock, CLOCK_REALTIME, NULL);
   LIBC_PROBE (wrlock_acquire_write, 1, rwlock);
   return result;
 }
diff --git a/nptl/tst-abstime.c b/nptl/tst-abstime.c
index 71610f8..f4c9f2d 100644
--- a/nptl/tst-abstime.c
+++ b/nptl/tst-abstime.c
@@ -47,12 +47,40 @@ th (void *arg)
       puts ("pthread_rwlock_timedrdlock did not return ETIMEDOUT");
       res = 1;
     }
+  r = pthread_rwlock_clockrdlock (&rw1, CLOCK_REALTIME, &t);
+  if (r != ETIMEDOUT)
+    {
+      puts ("pthread_rwlock_clockrdlock (CLOCK_REALTIME) "
+	    "did not return ETIMEDOUT");
+      res = 1;
+    }
+  r = pthread_rwlock_clockrdlock (&rw1, CLOCK_MONOTONIC, &t);
+  if (r != ETIMEDOUT)
+    {
+      puts ("pthread_rwlock_clockrdlock (CLOCK_MONOTONIC) "
+	    "did not return ETIMEDOUT");
+      res = 1;
+    }
   r = pthread_rwlock_timedwrlock (&rw2, &t);
   if (r != ETIMEDOUT)
     {
       puts ("pthread_rwlock_timedwrlock did not return ETIMEDOUT");
       res = 1;
     }
+  r = pthread_rwlock_clockwrlock (&rw2, CLOCK_REALTIME, &t);
+  if (r != ETIMEDOUT)
+    {
+      puts ("pthread_rwlock_clockwrlock(CLOCK_REALTIME) "
+	    "did not return ETIMEDOUT");
+      res = 1;
+    }
+  r = pthread_rwlock_clockwrlock (&rw2, CLOCK_MONOTONIC, &t);
+  if (r != ETIMEDOUT)
+    {
+      puts ("pthread_rwlock_clockwrlock(CLOCK_MONOTONIC) "
+	    "did not return ETIMEDOUT");
+      res = 1;
+    }
   return (void *) res;
 }
 
diff --git a/nptl/tst-rwlock14.c b/nptl/tst-rwlock14.c
index 6f57169..525ceac 100644
--- a/nptl/tst-rwlock14.c
+++ b/nptl/tst-rwlock14.c
@@ -91,6 +91,30 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("first rwlock_clockrdlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("first rwlock_clockrdlock (CLOCK_REALTIME) did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("first rwlock_clockrdlock (CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("first rwlock_clockrdlock (CLOCK_MONOTONIC) did not return EINVAL");
+      result = 1;
+    }
+
   e = pthread_rwlock_timedwrlock (&r, &ts);
   if (e == 0)
     {
@@ -103,6 +127,30 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("first rwlock_clockwrlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("first rwlock_clockwrlock (CLOCK_REALTIME) did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("first rwlock_clockwrlock (CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("first rwlock_clockwrlock (CLOCK_MONOTONIC) did not return EINVAL");
+      result = 1;
+    }
+
   ts.tv_nsec = 1000000000;
 
   e = pthread_rwlock_timedrdlock (&r, &ts);
@@ -117,6 +165,31 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("second rwlock_clockrdlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("second rwlock_clockrdlock (CLOCK_REALTIME) did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("second rwlock_clockrdlock (CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("second rwlock_clockrdlock (CLOCK_MONOTONIC) "
+	    "did not return EINVAL");
+      result = 1;
+    }
+
   e = pthread_rwlock_timedwrlock (&r, &ts);
   if (e == 0)
     {
@@ -129,6 +202,32 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("second rwlock_clockwrlock (CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("second rwlock_clockwrlock (CLOCK_MONOTONIC) "
+	    "did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("second rwlock_clockwrlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("second rwlock_clockwrlock (CLOCK_REALTIME) "
+	    "did not return EINVAL");
+      result = 1;
+    }
+
   ts.tv_nsec = (__typeof (ts.tv_nsec)) 0x100001000LL;
   if ((__typeof (ts.tv_nsec)) 0x100001000LL != 0x100001000LL)
     ts.tv_nsec = 2000000000;
@@ -145,6 +244,30 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("third rwlock_clockrdlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("third rwlock_clockrdlock (CLOCK_REALTIME) did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockrdlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("third rwlock_clockrdlock(CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("third rwlock_clockrdlock (CLOCK_MONOTONIC) did not return EINVAL");
+      result = 1;
+    }
+
   e = pthread_rwlock_timedwrlock (&r, &ts);
   if (e == 0)
     {
@@ -157,6 +280,30 @@ do_test (void)
       result = 1;
     }
 
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_REALTIME, &ts);
+  if (e == 0)
+    {
+      puts ("third rwlock_clockwrlock (CLOCK_REALTIME) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("third rwlock_clockwrlock (CLOCK_REALTIME) did not return EINVAL");
+      result = 1;
+    }
+
+  e = pthread_rwlock_clockwrlock (&r, CLOCK_MONOTONIC, &ts);
+  if (e == 0)
+    {
+      puts ("third rwlock_clockwrlock (CLOCK_MONOTONIC) did not fail");
+      result = 1;
+    }
+  else if (e != EINVAL)
+    {
+      puts ("third rwlock_clockwrlock (CLOCK_MONOTONIC) did not return EINVAL");
+      result = 1;
+    }
+
   if (result == 0)
     puts ("no bugs");
 
diff --git a/nptl/tst-rwlock6.c b/nptl/tst-rwlock6.c
index 67119fa..708915e 100644
--- a/nptl/tst-rwlock6.c
+++ b/nptl/tst-rwlock6.c
@@ -25,6 +25,11 @@
 #include <support/timespec.h>
 
 
+/* A bogus clock value that tells run_test to use
+   pthread_rwlock_timedrdlock and pthread_rwlock_timedwrlock rather
+   than pthread_rwlock_clockrdlock and pthread_rwlock_clockwrlock. */
+#define CLOCK_USE_TIMEDLOCK (-1)
+
 static int kind[] =
   {
     PTHREAD_RWLOCK_PREFER_READER_NP,
@@ -32,75 +37,91 @@ static int kind[] =
     PTHREAD_RWLOCK_PREFER_WRITER_NP,
   };
 
+struct thread_args {
+  pthread_rwlock_t *rwlock;
+  clockid_t clockid;
+  const char *fnname;
+};
 
 static void *
 tf (void *arg)
 {
-  pthread_rwlock_t *r = arg;
+  struct thread_args *args = arg;
+  pthread_rwlock_t *r = args->rwlock;
+  const clockid_t clockid = args->clockid;
+  const clockid_t clockid_for_get =
+    (clockid == CLOCK_USE_TIMEDLOCK) ? CLOCK_REALTIME : clockid;
+  const char *fnname = args->fnname;
 
   /* Timeout: 0.3 secs.  */
   struct timespec ts_start;
-  (void) clock_gettime(CLOCK_REALTIME, &ts_start);
+  (void) clock_gettime (clockid_for_get, &ts_start);
 
   struct timespec ts_timeout = {0, 300000000};
-  timespec_add(&ts_timeout, &ts_start, &ts_timeout);
+  timespec_add (&ts_timeout, &ts_start, &ts_timeout);
 
-  puts ("child calling timedrdlock");
+  printf ("child calling %srdlock\n", fnname);
 
-  int err = pthread_rwlock_timedrdlock (r, &ts_timeout);
+  int err = (clockid == CLOCK_USE_TIMEDLOCK)
+    ? pthread_rwlock_timedrdlock (r, &ts_timeout)
+    : pthread_rwlock_clockrdlock (r, clockid, &ts_timeout);
   if (err == 0)
     {
-      puts ("rwlock_timedrdlock returned");
+      printf ("%srdlock returned\n", fnname);
       pthread_exit ((void *) 1l);
     }
 
   if (err != ETIMEDOUT)
     {
-      printf ("err = %s (%d), expected %s (%d)\n",
-	      strerror (err), err, strerror (ETIMEDOUT), ETIMEDOUT);
+      printf ("%srdlock: err = %s (%d), expected %s (%d)\n",
+	      fnname, strerror (err), err, strerror (ETIMEDOUT), ETIMEDOUT);
       pthread_exit ((void *) 1l);
     }
 
-  puts ("1st child timedrdlock done");
+  printf ("1st child %srdlock done\n", fnname);
 
   struct timespec ts_end;
-  (void) clock_gettime (CLOCK_REALTIME, &ts_end);
+  (void) clock_gettime (clockid_for_get, &ts_end);
 
   struct timespec ts_duration;
-  timespec_sub(&ts_duration, &ts_end, &ts_start);
+  timespec_sub (&ts_duration, &ts_end, &ts_start);
 
   if (ts_duration.tv_sec !=0 || ts_duration.tv_nsec < 200000000)
     {
-      puts ("timeout too short");
+      printf ("%srdlock: timeout too short\n", fnname);
       pthread_exit ((void *) 1l);
     }
 
-  (void) clock_gettime (CLOCK_REALTIME, &ts_timeout);
+  (void) clock_gettime (clockid_for_get, &ts_timeout);
   ts_timeout.tv_sec += 10;
   /* Note that the following operation makes ts invalid.  */
   ts_timeout.tv_nsec += 1000000000;
 
-  err = pthread_rwlock_timedrdlock (r, &ts_timeout);
+  err = (clockid == CLOCK_USE_TIMEDLOCK)
+    ? pthread_rwlock_timedrdlock (r, &ts_timeout)
+    : pthread_rwlock_clockrdlock (r, clockid, &ts_timeout);
   if (err == 0)
     {
-      puts ("2nd timedrdlock succeeded");
+      printf ("2nd %srdlock succeeded\n", fnname);
       pthread_exit ((void *) 1l);
     }
   if (err != EINVAL)
     {
-      puts ("2nd timedrdlock did not return EINVAL");
+      printf ("2nd %srdlock did not return EINVAL\n", fnname);
       pthread_exit ((void *) 1l);
     }
 
-  puts ("2nd child timedrdlock done");
+  printf ("2nd child %srdlock done\n", fnname);
 
   return NULL;
 }
 
 
 static int
-do_test (void)
+do_test_clock (clockid_t clockid, const char *fnname)
 {
+  const clockid_t clockid_for_get =
+    (clockid == CLOCK_USE_TIMEDLOCK) ? CLOCK_REALTIME : clockid;
   size_t cnt;
   for (cnt = 0; cnt < sizeof (kind) / sizeof (kind[0]); ++cnt)
     {
@@ -132,53 +153,63 @@ do_test (void)
 	}
 
       struct timespec ts;
-      (void) clock_gettime (CLOCK_REALTIME, &ts);
+      (void) clock_gettime (clockid_for_get, &ts);
       ++ts.tv_sec;
 
       /* Get a write lock.  */
-      int e = pthread_rwlock_timedwrlock (&r, &ts);
+      int e = (clockid == CLOCK_USE_TIMEDLOCK)
+	? pthread_rwlock_timedwrlock (&r, &ts)
+	: pthread_rwlock_clockwrlock (&r, clockid, &ts);
       if (e != 0)
 	{
-	  printf ("round %Zu: rwlock_timedwrlock failed (%d)\n", cnt, e);
+	  printf ("round %Zu: %swrlock failed (%d)\n", cnt, fnname, e);
 	  exit (1);
 	}
 
-      puts ("1st timedwrlock done");
+      printf ("1st %swrlock done\n", fnname);
 
-      (void) clock_gettime (CLOCK_REALTIME, &ts);
+      (void) clock_gettime (clockid, &ts);
       ++ts.tv_sec;
-      e = pthread_rwlock_timedrdlock (&r, &ts);
+      e = (clockid == CLOCK_USE_TIMEDLOCK)
+	? pthread_rwlock_timedrdlock (&r, &ts)
+	: pthread_rwlock_clockrdlock (&r, clockid, &ts);
       if (e == 0)
 	{
-	  puts ("timedrdlock succeeded");
+	  printf ("%srdlock succeeded\n", fnname);
 	  exit (1);
 	}
       if (e != EDEADLK)
 	{
-	  puts ("timedrdlock did not return EDEADLK");
+	  printf ("%srdlock did not return EDEADLK\n", fnname);
 	  exit (1);
 	}
 
-      puts ("1st timedrdlock done");
+      printf ("1st %srdlock done\n", fnname);
 
-      (void) clock_gettime (CLOCK_REALTIME, &ts);
+      (void) clock_gettime (clockid_for_get, &ts);
       ++ts.tv_sec;
-      e = pthread_rwlock_timedwrlock (&r, &ts);
+      e = (clockid == CLOCK_USE_TIMEDLOCK)
+	? pthread_rwlock_timedwrlock (&r, &ts)
+	: pthread_rwlock_clockwrlock (&r, clockid, &ts);
       if (e == 0)
 	{
-	  puts ("2nd timedwrlock succeeded");
+	  printf ("2nd %swrlock succeeded\n", fnname);
 	  exit (1);
 	}
       if (e != EDEADLK)
 	{
-	  puts ("2nd timedwrlock did not return EDEADLK");
+	  printf ("2nd %swrlock did not return EDEADLK\n", fnname);
 	  exit (1);
 	}
 
-      puts ("2nd timedwrlock done");
+      printf ("2nd %swrlock done\n", fnname);
 
       pthread_t th;
-      if (pthread_create (&th, NULL, tf, &r) != 0)
+      struct thread_args args;
+      args.rwlock = &r;
+      args.clockid = clockid;
+      args.fnname = fnname;
+      if (pthread_create (&th, NULL, tf, &args) != 0)
 	{
 	  printf ("round %Zu: create failed\n", cnt);
 	  exit (1);
@@ -210,5 +241,13 @@ do_test (void)
   return 0;
 }
 
+static int do_test (void)
+{
+  do_test_clock (CLOCK_USE_TIMEDLOCK, "timed");
+  do_test_clock (CLOCK_REALTIME, "clock(realtime)");
+  do_test_clock (CLOCK_MONOTONIC, "clock(monotonic)");
+  return 0;
+}
+
 #define TEST_FUNCTION do_test ()
 #include "../test-skeleton.c"
diff --git a/nptl/tst-rwlock7.c b/nptl/tst-rwlock7.c
index 812506c..0bccd18 100644
--- a/nptl/tst-rwlock7.c
+++ b/nptl/tst-rwlock7.c
@@ -25,6 +25,11 @@
 #include <support/timespec.h>
 
 
+/* A bogus clock value that tells run_test to use
+   pthread_rwlock_timedrdlock and pthread_rwlock_timedwrlock rather
+   than pthread_rwlock_clockrdlock and pthread_rwlock_clockwrlock. */
+#define CLOCK_USE_TIMEDLOCK (-1)
+
 static int kind[] =
   {
     PTHREAD_RWLOCK_PREFER_READER_NP,
@@ -32,22 +37,34 @@ static int kind[] =
     PTHREAD_RWLOCK_PREFER_WRITER_NP,
   };
 
+struct thread_args
+{
+  pthread_rwlock_t *rwlock;
+  clockid_t clockid;
+  const char *fnname;
+};
 
 static void *
 tf (void *arg)
 {
-  pthread_rwlock_t *r = arg;
+  struct thread_args *args = arg;
+  pthread_rwlock_t *r = args->rwlock;
+  clockid_t clockid = args->clockid;
+  const char *fnname = args->fnname;
 
   /* Timeout: 0.3 secs.  */
   struct timespec ts_start;
-  (void) clock_gettime (CLOCK_REALTIME, &ts_start);
+  (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK)
+			? CLOCK_REALTIME : clockid, &ts_start);
   struct timespec ts_timeout = {0, 300000000};
   timespec_add(&ts_timeout, &ts_start, &ts_timeout);
 
-  int err = pthread_rwlock_timedwrlock (r, &ts_timeout);
+  int err = (clockid == CLOCK_USE_TIMEDLOCK)
+    ? pthread_rwlock_timedwrlock (r, &ts_timeout)
+    : pthread_rwlock_clockwrlock (r, clockid, &ts_timeout);
   if (err == 0)
     {
-      puts ("rwlock_timedwrlock returned");
+      printf ("pthread_rwlock_%swrlock returned\n", fnname);
       pthread_exit ((void *) 1l);
     }
 
@@ -57,44 +74,49 @@ tf (void *arg)
 	      strerror (err), err, strerror (ETIMEDOUT), ETIMEDOUT);
       pthread_exit ((void *) 1l);
     }
-  puts ("child: timedwrlock failed with ETIMEDOUT");
+  printf ("child: pthread_rwlock_%swrlock failed with ETIMEDOUT\n", fnname);
 
   struct timespec ts_end;
-  (void) clock_gettime (CLOCK_REALTIME, &ts_end);
+  (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK)
+			? CLOCK_REALTIME : clockid, &ts_end);
   struct timespec ts_diff;
   timespec_sub (&ts_diff, &ts_end, &ts_start);
 
   if (ts_diff.tv_sec != 0 || ts_diff.tv_nsec < 200000000)
     {
-      puts ("timeout too short");
+      printf ("pthread_rwlock_%srwlock timeout too short: %ld.%09ld\n",
+	      fnname, (long)ts_diff.tv_sec, (long)ts_diff.tv_nsec);
       pthread_exit ((void *) 1l);
     }
 
   struct timespec ts_invalid;
-  (void) clock_gettime (CLOCK_REALTIME, &ts_invalid);
+  (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK)
+			? CLOCK_REALTIME : clockid, &ts_invalid);
   ts_invalid.tv_sec += 10;
   /* Note that the following operation makes ts invalid.  */
   ts_invalid.tv_nsec += 1000000000000;
 
-  err = pthread_rwlock_timedwrlock (r, &ts_invalid);
+  err = (clockid == CLOCK_USE_TIMEDLOCK)
+	 ? pthread_rwlock_timedwrlock (r, &ts_invalid)
+	 : pthread_rwlock_clockwrlock (r, clockid, &ts_invalid);
   if (err == 0)
     {
-      puts ("2nd timedwrlock succeeded");
+      printf ("2nd pthread_%srwlock succeeded\n", fnname);
       pthread_exit ((void *) 1l);
     }
   if (err != EINVAL)
     {
-      puts ("2nd timedwrlock did not return EINVAL");
+      printf ("2nd pthread_%srwlock did not return EINVAL\n", fnname);
       pthread_exit ((void *) 1l);
     }
-  puts ("child: timedwrlock failed with EINVAL");
+  printf ("child: %s failed with EINVAL\n", fnname);
 
   return NULL;
 }
 
 
 static int
-do_test (void)
+do_test_clock (clockid_t clockid, const char *fnname)
 {
   size_t cnt;
   for (cnt = 0; cnt < sizeof (kind) / sizeof (kind[0]); ++cnt)
@@ -127,20 +149,27 @@ do_test (void)
 	}
 
       struct timespec ts;
-      (void) clock_gettime (CLOCK_REALTIME, &ts);
+      (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK) ?
+			    CLOCK_REALTIME: clockid, &ts);
 
       ++ts.tv_sec;
 
       /* Get a read lock.  */
-      if (pthread_rwlock_timedrdlock (&r, &ts) != 0)
+      if ((clockid == CLOCK_USE_TIMEDLOCK)
+	  ? pthread_rwlock_timedrdlock (&r, &ts)
+	  : pthread_rwlock_clockrdlock (&r, clockid, &ts) != 0)
 	{
-	  printf ("round %Zu: rwlock_timedrdlock failed\n", cnt);
+	  printf ("round %Zu: pthread_rwlock%srdlock failed\n", cnt, fnname);
 	  exit (1);
 	}
-      printf ("%zu: got timedrdlock\n", cnt);
+      printf ("%zu: got pthread_rwlock_%srdlock\n", cnt, fnname);
 
+      struct thread_args args;
+      args.rwlock = &r;
+      args.clockid = clockid;
+      args.fnname = fnname;
       pthread_t th;
-      if (pthread_create (&th, NULL, tf, &r) != 0)
+      if (pthread_create (&th, NULL, tf, &args) != 0)
 	{
 	  printf ("round %Zu: create failed\n", cnt);
 	  exit (1);
@@ -168,5 +197,15 @@ do_test (void)
   return 0;
 }
 
+static int
+do_test (void)
+{
+  do_test_clock (CLOCK_USE_TIMEDLOCK, "timed");
+  do_test_clock (CLOCK_MONOTONIC, "clock(monotonic)");
+  do_test_clock (CLOCK_REALTIME, "clock(realtime)");
+
+  return 0;
+}
+
 #define TEST_FUNCTION do_test ()
 #include "../test-skeleton.c"
diff --git a/nptl/tst-rwlock9.c b/nptl/tst-rwlock9.c
index ff15f90..2691f6a 100644
--- a/nptl/tst-rwlock9.c
+++ b/nptl/tst-rwlock9.c
@@ -38,12 +38,28 @@
 # define KIND PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP
 #endif
 
+/* A bogus clock value that tells the tests to use
+   pthread_rwlock_timedrdlock and pthread_rwlock_timedwrlock rather
+   than pthread_rwlock_clockrdlock and pthread_rwlock_clockwrlock. */
+#define CLOCK_USE_TIMEDLOCK (-1)
+
 static pthread_rwlock_t lock;
 
+struct thread_args
+{
+  int nr;
+  clockid_t clockid;
+  const char *fnname;
+};
 
 static void *
-writer_thread (void *nr)
+writer_thread (void *arg)
 {
+  struct thread_args *args = arg;
+  const int nr = args->nr;
+  const clockid_t clockid = args->clockid;
+  const char *fnname = args->fnname;
+
   struct timespec ts;
   struct timespec delay;
   int n;
@@ -56,7 +72,8 @@ writer_thread (void *nr)
       int e;
       do
 	{
-	  (void) clock_gettime (CLOCK_REALTIME, &ts);
+	  (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK)
+				? CLOCK_REALTIME : clockid, &ts);
 
 	  ts.tv_nsec += 2 * TIMEOUT;
 	  if (ts.tv_nsec >= 1000000000)
@@ -65,18 +82,20 @@ writer_thread (void *nr)
 	      ++ts.tv_sec;
 	    }
 
-	  printf ("writer thread %ld tries again\n", (long int) nr);
+	  printf ("writer thread %d tries again\n", nr);
 
-	  e = pthread_rwlock_timedwrlock (&lock, &ts);
+	  e = (clockid == CLOCK_USE_TIMEDLOCK)
+	    ? pthread_rwlock_timedwrlock (&lock, &ts)
+	    : pthread_rwlock_clockwrlock (&lock, clockid, &ts);
 	  if (e != 0 && e != ETIMEDOUT)
 	    {
-	      puts ("timedwrlock failed");
+	      printf ("%swrlock failed", fnname);
 	      exit (1);
 	    }
 	}
       while (e == ETIMEDOUT);
 
-      printf ("writer thread %ld succeeded\n", (long int) nr);
+      printf ("writer thread %d succeeded\n", nr);
 
       nanosleep (&delay, NULL);
 
@@ -86,7 +105,7 @@ writer_thread (void *nr)
 	  exit (1);
 	}
 
-      printf ("writer thread %ld released\n", (long int) nr);
+      printf ("writer thread %d released\n", nr);
     }
 
   return NULL;
@@ -94,8 +113,13 @@ writer_thread (void *nr)
 
 
 static void *
-reader_thread (void *nr)
+reader_thread (void *arg)
 {
+  struct thread_args *args = arg;
+  const int nr = args->nr;
+  const clockid_t clockid = args->clockid;
+  const char *fnname = args->fnname;
+
   struct timespec ts;
   struct timespec delay;
   int n;
@@ -108,8 +132,8 @@ reader_thread (void *nr)
       int e;
       do
 	{
-	  (void) clock_gettime (CLOCK_REALTIME, &ts);
-
+	  (void) clock_gettime ((clockid == CLOCK_USE_TIMEDLOCK)
+				? CLOCK_REALTIME : clockid, &ts);
 	  ts.tv_nsec += TIMEOUT;
 	  if (ts.tv_nsec >= 1000000000)
 	    {
@@ -117,18 +141,20 @@ reader_thread (void *nr)
 	      ++ts.tv_sec;
 	    }
 
-	  printf ("reader thread %ld tries again\n", (long int) nr);
+	  printf ("reader thread %d tries again\n", nr);
 
-	  e = pthread_rwlock_timedrdlock (&lock, &ts);
+	  e = (clockid == CLOCK_USE_TIMEDLOCK)
+	    ? pthread_rwlock_timedrdlock (&lock, &ts)
+	    : pthread_rwlock_clockrdlock (&lock, clockid, &ts);
 	  if (e != 0 && e != ETIMEDOUT)
 	    {
-	      puts ("timedrdlock failed");
+	      printf ("%srdlock failed\n", fnname);
 	      exit (1);
 	    }
 	}
       while (e == ETIMEDOUT);
 
-      printf ("reader thread %ld succeeded\n", (long int) nr);
+      printf ("reader thread %d succeeded\n", nr);
 
       nanosleep (&delay, NULL);
 
@@ -138,7 +164,7 @@ reader_thread (void *nr)
 	  exit (1);
 	}
 
-      printf ("reader thread %ld released\n", (long int) nr);
+      printf ("reader thread %d released\n", nr);
     }
 
   return NULL;
@@ -146,7 +172,7 @@ reader_thread (void *nr)
 
 
 static int
-do_test (void)
+do_test_clock (clockid_t clockid, const char *fnname)
 {
   pthread_t thwr[NWRITERS];
   pthread_t thrd[NREADERS];
@@ -178,21 +204,31 @@ do_test (void)
   /* Make sure we see all message, even those on stdout.  */
   setvbuf (stdout, NULL, _IONBF, 0);
 
-  for (n = 0; n < NWRITERS; ++n)
+  struct thread_args wargs[NWRITERS];
+  for (n = 0; n < NWRITERS; ++n) {
+    wargs[n].nr = n;
+    wargs[n].clockid = clockid;
+    wargs[n].fnname = fnname;
     if (pthread_create (&thwr[n], NULL, writer_thread,
-			(void *) (long int) n) != 0)
+			&wargs[n]) != 0)
       {
 	puts ("writer create failed");
 	exit (1);
       }
+  }
 
-  for (n = 0; n < NREADERS; ++n)
+  struct thread_args rargs[NREADERS];
+  for (n = 0; n < NREADERS; ++n) {
+    rargs[n].nr = n;
+    rargs[n].clockid = clockid;
+    rargs[n].fnname = fnname;
     if (pthread_create (&thrd[n], NULL, reader_thread,
-			(void *) (long int) n) != 0)
+			&rargs[n]) != 0)
       {
 	puts ("reader create failed");
 	exit (1);
       }
+  }
 
   /* Wait for all the threads.  */
   for (n = 0; n < NWRITERS; ++n)
@@ -211,6 +247,16 @@ do_test (void)
   return 0;
 }
 
+static int
+do_test (void)
+{
+  do_test_clock (CLOCK_USE_TIMEDLOCK, "timed");
+  do_test_clock (CLOCK_REALTIME, "clock(realtime)");
+  do_test_clock (CLOCK_MONOTONIC, "clock(monotonic)");
+
+  return 0;
+}
+
 #undef TIMEOUT
 #define TIMEOUT 30
 #define TEST_FUNCTION do_test ()
diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h
index d4fe9d9..3c06d77 100644
--- a/sysdeps/nptl/pthread.h
+++ b/sysdeps/nptl/pthread.h
@@ -907,6 +907,10 @@ extern int pthread_rwlock_tryrdlock (pthread_rwlock_t *__rwlock)
 extern int pthread_rwlock_timedrdlock (pthread_rwlock_t *__restrict __rwlock,
 				       const struct timespec *__restrict
 				       __abstime) __THROWNL __nonnull ((1, 2));
+extern int pthread_rwlock_clockrdlock (pthread_rwlock_t *__restrict __rwlock,
+				       clockid_t __clockid,
+				       const struct timespec *__restrict
+				       __abstime) __THROWNL __nonnull ((1, 3));
 # endif
 
 /* Acquire write lock for RWLOCK.  */
@@ -922,6 +926,10 @@ extern int pthread_rwlock_trywrlock (pthread_rwlock_t *__rwlock)
 extern int pthread_rwlock_timedwrlock (pthread_rwlock_t *__restrict __rwlock,
 				       const struct timespec *__restrict
 				       __abstime) __THROWNL __nonnull ((1, 2));
+extern int pthread_rwlock_clockwrlock (pthread_rwlock_t *__restrict __rwlock,
+				       clockid_t __clockid,
+				       const struct timespec *__restrict
+				       __abstime) __THROWNL __nonnull ((1, 3));
 # endif
 
 /* Unlock RWLOCK.  */
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
index aaa1c3b..70f04cc 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
@@ -246,6 +246,8 @@ GLIBC_2.3.4 pthread_getaffinity_np F
 GLIBC_2.3.4 pthread_setaffinity_np F
 GLIBC_2.3.4 pthread_setschedprio F
 GLIBC_2.30 pthread_cond_clockwait F
+GLIBC_2.30 pthread_rwlock_clockrdlock F
+GLIBC_2.30 pthread_rwlock_clockwrlock F
 GLIBC_2.30 sem_clockwait F
 GLIBC_2.4 pthread_mutex_consistent_np F
 GLIBC_2.4 pthread_mutex_getprioceiling F
