[BZ #357]

Update.
2004-09-02  Steven Munroe  <sjmunroe@us.ibm.com>

	[BZ #357]
	* stdlib/tst-setcontext.c (test_stack): Added test for stack clobber.
	(main): Call test_stack.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext.S
	(__getcontext): Push stack frame then save parms in local frame.
	Improve instruction scheduling.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext.S
	(__swapcontext): Likewise.

24 files changed, 496 insertions, 40 deletions

diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index 2aa77d9133..6306a7b0c6 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,62 @@
+2004-09-02  Ulrich Drepper  <drepper@redhat.com>
+
+	* sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h (pthread_cond_t):
+	Rename __data.__clock to __data.__nwaiters, make it unsigned int.
+	* sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h (pthread_cond_t):
+	Likewise.
+	* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S:
+	Decrement __nwaiters.  If pthread_cond_destroy has been called and
+	this is the last waiter, signal pthread_cond_destroy caller and
+	avoid using the pthread_cond_t structure after unlock.
+	* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S: Likewise.
+	* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S: Likewise.
+	Read clock type from the least significant bits of __nwaiters instead
+	of __clock.
+	* sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S: Likewise.
+	* sysdeps/unix/sysv/linux/internaltypes.h: Define COND_CLOCK_BITS.
+
+2004-08-31  Jakub Jelinek  <jakub@redhat.com>
+
+	[BZ #342]
+	* Makefile (tests): Add tst-cond20 and tst-cond21.
+	* tst-cond20.c: New test.
+	* tst-cond21.c: New test.
+	* sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h
+	(pthread_cond_t): Rename __data.__clock to __data.__nwaiters, make
+	it unsigned int.
+	* sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h (pthread_cond_t):
+	Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h
+	(pthread_cond_t): Likewise.
+	* sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h (pthread_cond_t):
+	Likewise.
+	* sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h (pthread_cond_t):
+	Likewise.
+	* sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h (pthread_cond_t):
+	Likewise.
+	* sysdeps/unix/sysv/linux/lowlevelcond.sym (cond_clock): Remove.
+	(cond_nwaiters): New.
+	(clock_bits): New.
+	* pthread_cond_destroy.c (__pthread_cond_destroy): Return EBUSY
+	if there are waiters not signalled yet.
+	Wait until all already signalled waiters wake up.
+	* sysdeps/pthread/pthread_cond_wait.c (__condvar_cleanup): Decrement
+	__nwaiters.  If pthread_cond_destroy has been called and this is the
+	last waiter, signal pthread_cond_destroy caller and avoid using
+	the pthread_cond_t structure after unlock.
+	(__pthread_cond_wait): Increment __nwaiters in the beginning,
+	decrement it when leaving.  If pthread_cond_destroy has been called
+	and this is the last waiter, signal pthread_cond_destroy caller.
+	* sysdeps/pthread/pthread_cond_timedwait.c (__pthread_cond_timedwait):
+	Likewise.  Read clock type from the least significant bits of
+	__nwaiters instead of __clock.
+	* pthread_condattr_setclock.c (pthread_condattr_setclock): Check
+	whether clock ID can be encoded in COND_CLOCK_BITS bits.
+	* pthread_condattr_getclock.c (pthread_condattr_getclock): Decode
+	clock type just from the last COND_CLOCK_BITS bits of value.
+	* pthread_cond_init.c (__pthread_cond_init): Initialize __nwaiters
+	instead of __clock, just from second bit of condattr's value.
+
 2004-08-30  Jakub Jelinek  <jakub@redhat.com>
 
 	* sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h: Include
diff --git a/nptl/Makefile b/nptl/Makefile
index e797f4d486..e75752f801 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -193,6 +193,7 @@ tests = tst-attr1 tst-attr2 tst-attr3 \
 	tst-cond1 tst-cond2 tst-cond3 tst-cond4 tst-cond5 tst-cond6 tst-cond7 \
 	tst-cond8 tst-cond9 tst-cond10 tst-cond11 tst-cond12 tst-cond13 \
 	tst-cond14 tst-cond15 tst-cond16 tst-cond17 tst-cond18 tst-cond19 \
+	tst-cond20 tst-cond21 \
 	tst-rwlock1 tst-rwlock2 tst-rwlock3 tst-rwlock4 tst-rwlock5 \
 	tst-rwlock6 tst-rwlock7 tst-rwlock8 tst-rwlock9 tst-rwlock10 \
 	tst-rwlock11 tst-rwlock12 tst-rwlock13 tst-rwlock14 \
diff --git a/nptl/pthread_cond_destroy.c b/nptl/pthread_cond_destroy.c
index 5ade3e63db..0208d18ce4 100644
--- a/nptl/pthread_cond_destroy.c
+++ b/nptl/pthread_cond_destroy.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -17,6 +17,7 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <errno.h>
 #include <shlib-compat.h>
 #include "pthreadP.h"
 
@@ -25,6 +26,35 @@ int
 __pthread_cond_destroy (cond)
      pthread_cond_t *cond;
 {
+  /* Make sure we are alone.  */
+  lll_mutex_lock (cond->__data.__lock);
+
+  if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
+    {
+      /* If there are still some waiters which have not been
+	 woken up, this is an application bug.  */
+      lll_mutex_unlock (cond->__data.__lock);
+      return EBUSY;
+    }
+
+  /* Tell pthread_cond_*wait that this condvar is being destroyed.  */
+  cond->__data.__total_seq = -1ULL;
+
+  /* If there are waiters which have been already signalled or
+     broadcasted, but still are using the pthread_cond_t structure,
+     pthread_cond_destroy needs to wait for them.  */
+  unsigned int nwaiters = cond->__data.__nwaiters;
+  while (nwaiters >= (1 << COND_CLOCK_BITS))
+    {
+      lll_mutex_unlock (cond->__data.__lock);
+
+      lll_futex_wait (&cond->__data.__nwaiters, nwaiters);
+
+      lll_mutex_lock (cond->__data.__lock);
+
+      nwaiters = cond->__data.__nwaiters;
+    }
+
   return 0;
 }
 versioned_symbol (libpthread, __pthread_cond_destroy,
diff --git a/nptl/pthread_cond_init.c b/nptl/pthread_cond_init.c
index f5fbd64e96..03ac59dbd2 100644
--- a/nptl/pthread_cond_init.c
+++ b/nptl/pthread_cond_init.c
@@ -32,8 +32,9 @@ __pthread_cond_init (cond, cond_attr)
 
   cond->__data.__lock = LLL_MUTEX_LOCK_INITIALIZER;
   cond->__data.__futex = 0;
-  cond->__data.__clock = (icond_attr == NULL
-			  ? CLOCK_REALTIME : (icond_attr->value & 0xfe) >> 1);
+  cond->__data.__nwaiters = (icond_attr != NULL
+			     && ((icond_attr->value & (COND_CLOCK_BITS << 1))
+				 >> 1));
   cond->__data.__total_seq = 0;
   cond->__data.__wakeup_seq = 0;
   cond->__data.__woken_seq = 0;
diff --git a/nptl/pthread_condattr_getclock.c b/nptl/pthread_condattr_getclock.c
index f8be655bf9..84de918a54 100644
--- a/nptl/pthread_condattr_getclock.c
+++ b/nptl/pthread_condattr_getclock.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
 
@@ -25,7 +25,7 @@ pthread_condattr_getclock (attr, clock_id)
      const pthread_condattr_t *attr;
      clockid_t *clock_id;
 {
-  *clock_id = ((((const struct pthread_condattr *) attr)->value) & 0xfe) >> 1;
-
+  *clock_id = (((((const struct pthread_condattr *) attr)->value) >> 1)
+	       & ((1 << COND_CLOCK_BITS) - 1));
   return 0;
 }
diff --git a/nptl/pthread_condattr_setclock.c b/nptl/pthread_condattr_setclock.c
index 0f1829c502..04e246b74d 100644
--- a/nptl/pthread_condattr_setclock.c
+++ b/nptl/pthread_condattr_setclock.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
 
@@ -17,6 +17,7 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <assert.h>
 #include <errno.h>
 #include <stdbool.h>
 #include <time.h>
@@ -45,8 +46,7 @@ pthread_condattr_setclock (attr, clock_id)
 
 	  INTERNAL_SYSCALL_DECL (err);
 	  int val;
-	  val = INTERNAL_SYSCALL (clock_getres, err, 2, CLOCK_MONOTONIC,
-				  &ts);
+	  val = INTERNAL_SYSCALL (clock_getres, err, 2, CLOCK_MONOTONIC, &ts);
 	  avail = INTERNAL_SYSCALL_ERROR_P (val, err) ? -1 : 1;
 	}
 
@@ -57,11 +57,16 @@ pthread_condattr_setclock (attr, clock_id)
 #endif
     }
   else if (clock_id != CLOCK_REALTIME)
+    /* If more clocks are allowed some day the storing of the clock ID
+       in the pthread_cond_t structure needs to be adjusted.  */
     return EINVAL;
 
+  /* Make sure the value fits in the bits we reserved.  */
+  assert (clock_id < (1 << COND_CLOCK_BITS));
+
   int *valuep = &((struct pthread_condattr *) attr)->value;
 
-  *valuep = (*valuep & ~0xfe) | (clock_id << 1);
+  *valuep = (*valuep & ~(1 << (COND_CLOCK_BITS + 1)) & ~1) | (clock_id << 1);
 
   return 0;
 }
diff --git a/nptl/sysdeps/pthread/pthread_cond_timedwait.c b/nptl/sysdeps/pthread/pthread_cond_timedwait.c
index 7de2b2936f..c6606c9bf9 100644
--- a/nptl/sysdeps/pthread/pthread_cond_timedwait.c
+++ b/nptl/sysdeps/pthread/pthread_cond_timedwait.c
@@ -67,6 +67,7 @@ __pthread_cond_timedwait (cond, mutex, abstime)
   /* We have one new user of the condvar.  */
   ++cond->__data.__total_seq;
   ++cond->__data.__futex;
+  cond->__data.__nwaiters += 1 << COND_CLOCK_BITS;
 
   /* Remember the mutex we are using here.  If there is already a
      different address store this is a bad user bug.  Do not store
@@ -98,7 +99,8 @@ __pthread_cond_timedwait (cond, mutex, abstime)
 	INTERNAL_SYSCALL_DECL (err);
 	int ret;
 	ret = INTERNAL_SYSCALL (clock_gettime, err, 2,
-				cond->__data.__clock, &rt);
+				cond->__data.__nwaiters & COND_CLOCK_BITS,
+				&rt);
 # ifndef __ASSUME_POSIX_TIMERS
 	if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (ret, err), 0))
 	  {
@@ -185,6 +187,16 @@ __pthread_cond_timedwait (cond, mutex, abstime)
   ++cond->__data.__woken_seq;
 
  bc_out:
+
+  cond->__data.__nwaiters -= 1 << COND_CLOCK_BITS;
+
+  /* If pthread_cond_destroy was called on this variable already,
+     notify the pthread_cond_destroy caller all waiters have left
+     and it can be successfully destroyed.  */
+  if (cond->__data.__total_seq == -1ULL
+      && cond->__data.__nwaiters < (1 << COND_CLOCK_BITS))
+    lll_futex_wake (&cond->__data.__nwaiters, 1);
+
   /* We are done with the condvar.  */
   lll_mutex_unlock (cond->__data.__lock);
 
diff --git a/nptl/sysdeps/pthread/pthread_cond_wait.c b/nptl/sysdeps/pthread/pthread_cond_wait.c
index 45187b5240..86669458a0 100644
--- a/nptl/sysdeps/pthread/pthread_cond_wait.c
+++ b/nptl/sysdeps/pthread/pthread_cond_wait.c
@@ -42,6 +42,7 @@ __condvar_cleanup (void *arg)
 {
   struct _condvar_cleanup_buffer *cbuffer =
     (struct _condvar_cleanup_buffer *) arg;
+  unsigned int destroying;
 
   /* We are going to modify shared data.  */
   lll_mutex_lock (cbuffer->cond->__data.__lock);
@@ -55,11 +56,25 @@ __condvar_cleanup (void *arg)
       ++cbuffer->cond->__data.__futex;
     }
 
+  cbuffer->cond->__data.__nwaiters -= 1 << COND_CLOCK_BITS;
+
+  /* If pthread_cond_destroy was called on this variable already,
+     notify the pthread_cond_destroy caller all waiters have left
+     and it can be successfully destroyed.  */
+  destroying = 0;
+  if (cbuffer->cond->__data.__total_seq == -1ULL
+      && cbuffer->cond->__data.__nwaiters < (1 << COND_CLOCK_BITS))
+    {
+      lll_futex_wake (&cbuffer->cond->__data.__nwaiters, 1);
+      destroying = 1;
+    }
+
   /* We are done.  */
   lll_mutex_unlock (cbuffer->cond->__data.__lock);
 
   /* Wake everybody to make sure no condvar signal gets lost.  */
-  lll_futex_wake (&cbuffer->cond->__data.__futex, INT_MAX);
+  if (! destroying)
+    lll_futex_wake (&cbuffer->cond->__data.__futex, INT_MAX);
 
   /* Get the mutex before returning unless asynchronous cancellation
      is in effect.  */
@@ -90,6 +105,7 @@ __pthread_cond_wait (cond, mutex)
   /* We have one new user of the condvar.  */
   ++cond->__data.__total_seq;
   ++cond->__data.__futex;
+  cond->__data.__nwaiters += 1 << COND_CLOCK_BITS;
 
   /* Remember the mutex we are using here.  If there is already a
      different address store this is a bad user bug.  Do not store
@@ -145,6 +161,16 @@ __pthread_cond_wait (cond, mutex)
   ++cond->__data.__woken_seq;
 
  bc_out:
+
+  cond->__data.__nwaiters -= 1 << COND_CLOCK_BITS;
+
+  /* If pthread_cond_destroy was called on this varaible already,
+     notify the pthread_cond_destroy caller all waiters have left
+     and it can be successfully destroyed.  */
+  if (cond->__data.__total_seq == -1ULL
+      && cond->__data.__nwaiters < (1 << COND_CLOCK_BITS))
+    lll_futex_wake (&cond->__data.__nwaiters, 1);
+
   /* We are done with the condvar.  */
   lll_mutex_unlock (cond->__data.__lock);
 
diff --git a/nptl/sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h
index 62c853cee9..fd20d572af 100644
--- a/nptl/sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h
@@ -81,7 +81,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h
index 8d7858a071..fb62c0d99b 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h
@@ -81,7 +81,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S
index eecec8aee3..699c2cb227 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S
+++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S
@@ -87,6 +87,7 @@ __pthread_cond_timedwait:
 	addl	$1, total_seq(%ebx)
 	adcl	$0, total_seq+4(%ebx)
 	addl	$1, cond_futex(%ebx)
+	addl	$(1 << clock_bits), cond_nwaiters(%ebx)
 
 #define FRAME_SIZE 24
 	subl	$FRAME_SIZE, %esp
@@ -104,8 +105,9 @@ __pthread_cond_timedwait:
 8:	movl	%ebx, %edx
 #ifdef __NR_clock_gettime
 	/* Get the clock number.  */
-	movl	cond_clock(%ebx), %ebx
-	/* Only clocks 0 and 1 are allowed.  Both are handled in the
+	movl	cond_nwaiters(%ebx), %ebx
+	andl	$((1 << clock_bits) - 1), %ebx
+	/* Only clocks 0 and 1 are allowed so far.  Both are handled in the
 	   kernel.  */
 	leal	4(%esp), %ecx
 	movl	$__NR_clock_gettime, %eax
@@ -226,7 +228,25 @@ __pthread_cond_timedwait:
 14:	addl	$1, woken_seq(%ebx)
 	adcl	$0, woken_seq+4(%ebx)
 
-24:	LOCK
+24:	subl	$(1 << clock_bits), cond_nwaiters(%ebx)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	movl	total_seq(%ebx), %eax
+	andl	total_seq+4(%ebx), %eax
+	cmpl	$0xffffffff, %eax
+	jne	25f
+	movl	cond_nwaiters(%ebx), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	25f
+
+	addl	$cond_nwaiters, %ebx
+	movl	$SYS_futex, %eax
+	movl	$FUTEX_WAKE, %ecx
+	movl	$1, %edx
+	ENTER_KERNEL
+	subl	$cond_nwaiters, %ebx
+
+25:	LOCK
 #if cond_lock == 0
 	subl	$1, (%ebx)
 #else
@@ -394,7 +414,27 @@ __condvar_tw_cleanup:
 	addl	$1, woken_seq(%ebx)
 	adcl	$0, woken_seq+4(%ebx)
 
-3:	LOCK
+3:	subl	$(1 << clock_bits), cond_nwaiters(%ebx)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	xorl	%edi, %edi
+	movl	total_seq(%ebx), %eax
+	andl	total_seq+4(%ebx), %eax
+	cmpl	$0xffffffff, %eax
+	jne	4f
+	movl	cond_nwaiters(%ebx), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	4f
+
+	addl	$cond_nwaiters, %ebx
+	movl	$SYS_futex, %eax
+	movl	$FUTEX_WAKE, %ecx
+	movl	$1, %edx
+	ENTER_KERNEL
+	subl	$cond_nwaiters, %ebx
+	movl	$1, %edi
+
+4:	LOCK
 #if cond_lock == 0
 	subl	$1, (%ebx)
 #else
@@ -410,13 +450,15 @@ __condvar_tw_cleanup:
 	call	__lll_mutex_unlock_wake
 
 	/* Wake up all waiters to make sure no signal gets lost.  */
-2:	addl	$cond_futex, %ebx
+2:	testl	%edi, %edi
+	jnz	5f
+	addl	$cond_futex, %ebx
 	movl	$FUTEX_WAKE, %ecx
 	movl	$SYS_futex, %eax
 	movl	$0x7fffffff, %edx
 	ENTER_KERNEL
 
-	movl	24+FRAME_SIZE(%esp), %eax
+5:	movl	24+FRAME_SIZE(%esp), %eax
 	call	__pthread_mutex_cond_lock
 
 	movl	%esi, (%esp)
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S
index 3fe7f8c17a..d282785151 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S
+++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S
@@ -80,6 +80,7 @@ __pthread_cond_wait:
 	addl	$1, total_seq(%ebx)
 	adcl	$0, total_seq+4(%ebx)
 	addl	$1, cond_futex(%ebx)
+	addl	$(1 << clock_bits), cond_nwaiters(%ebx)
 
 #define FRAME_SIZE 16
 	subl	$FRAME_SIZE, %esp
@@ -156,7 +157,25 @@ __pthread_cond_wait:
 	adcl	$0, woken_seq+4(%ebx)
 
 	/* Unlock */
-16:	LOCK
+16:	subl	$(1 << clock_bits), cond_nwaiters(%ebx)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	movl	total_seq(%ebx), %eax
+	andl	total_seq+4(%ebx), %eax
+	cmpl	$0xffffffff, %eax
+	jne	17f
+	movl	cond_nwaiters(%ebx), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	17f
+
+	addl	$cond_nwaiters, %ebx
+	movl	$SYS_futex, %eax
+	movl	$FUTEX_WAKE, %ecx
+	movl	$1, %edx
+	ENTER_KERNEL
+	subl	$cond_nwaiters, %ebx
+
+17:	LOCK
 #if cond_lock == 0
 	subl	$1, (%ebx)
 #else
@@ -286,7 +305,27 @@ __condvar_w_cleanup:
 	addl	$1, woken_seq(%ebx)
 	adcl	$0, woken_seq+4(%ebx)
 
-3:	LOCK
+3:	subl	$(1 << clock_bits), cond_nwaiters(%ebx)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	xorl	%edi, %edi
+	movl	total_seq(%ebx), %eax
+	andl	total_seq+4(%ebx), %eax
+	cmpl	$0xffffffff, %eax
+	jne	4f
+	movl	cond_nwaiters(%ebx), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	4f
+
+	addl	$cond_nwaiters, %ebx
+	movl	$SYS_futex, %eax
+	movl	$FUTEX_WAKE, %ecx
+	movl	$1, %edx
+	ENTER_KERNEL
+	subl	$cond_nwaiters, %ebx
+	movl	$1, %edi
+
+4:	LOCK
 #if cond_lock == 0
 	subl	$1, (%ebx)
 #else
@@ -302,13 +341,15 @@ __condvar_w_cleanup:
 	call	__lll_mutex_unlock_wake
 
 	/* Wake up all waiters to make sure no signal gets lost.  */
-2:	addl	$cond_futex, %ebx
+2:	testl	%edi, %edi
+	jnz	5f
+	addl	$cond_futex, %ebx
 	movl	$FUTEX_WAKE, %ecx
 	movl	$SYS_futex, %eax
 	movl	$0x7fffffff, %edx
 	ENTER_KERNEL
 
-	movl	20+FRAME_SIZE(%esp), %eax
+5:	movl	20+FRAME_SIZE(%esp), %eax
 	call	__pthread_mutex_cond_lock
 
 	movl	%esi, (%esp)
diff --git a/nptl/sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h
index 958af47162..5b442cbca7 100644
--- a/nptl/sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h
@@ -81,7 +81,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/internaltypes.h b/nptl/sysdeps/unix/sysv/linux/internaltypes.h
index 43b6856bbf..1dec19e57d 100644
--- a/nptl/sysdeps/unix/sysv/linux/internaltypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/internaltypes.h
@@ -75,6 +75,12 @@ struct pthread_condattr
 };
 
 
+/* The __NWAITERS field is used as a counter and to house the number
+   of bits which represent the clock.  COND_CLOCK_BITS is the number
+   of bits reserved for the clock.  */
+#define COND_CLOCK_BITS	1
+
+
 /* Read-write lock variable attribute data structure.  */
 struct pthread_rwlockattr
 {
diff --git a/nptl/sysdeps/unix/sysv/linux/lowlevelcond.sym b/nptl/sysdeps/unix/sysv/linux/lowlevelcond.sym
index 2e193e6d2e..c5e7978069 100644
--- a/nptl/sysdeps/unix/sysv/linux/lowlevelcond.sym
+++ b/nptl/sysdeps/unix/sysv/linux/lowlevelcond.sym
@@ -1,13 +1,16 @@
 #include <stddef.h>
+#include <sched.h>
 #include <bits/pthreadtypes.h>
+#include <internaltypes.h>
 
 --
 
 cond_lock	offsetof (pthread_cond_t, __data.__lock)
 cond_futex	offsetof (pthread_cond_t, __data.__futex)
-cond_clock	offsetof (pthread_cond_t, __data.__clock)
+cond_nwaiters	offsetof (pthread_cond_t, __data.__nwaiters)
 total_seq	offsetof (pthread_cond_t, __data.__total_seq)
 wakeup_seq	offsetof (pthread_cond_t, __data.__wakeup_seq)
 woken_seq	offsetof (pthread_cond_t, __data.__woken_seq)
 dep_mutex	offsetof (pthread_cond_t, __data.__mutex)
 broadcast_seq	offsetof (pthread_cond_t, __data.__broadcast_seq)
+clock_bits	COND_CLOCK_BITS
diff --git a/nptl/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h
index 5a000d30af..a493821c07 100644
--- a/nptl/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h
@@ -101,7 +101,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h
index 142286451c..17cfaa981d 100644
--- a/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h
@@ -100,7 +100,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h
index b8afbc50b5..5bf3aff46a 100644
--- a/nptl/sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h
@@ -82,7 +82,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h
index e86dd000a1..34d3df7abb 100644
--- a/nptl/sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h
@@ -101,7 +101,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    unsigned int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h
index a7bc5816cc..e5cc605f24 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h
@@ -100,7 +100,7 @@ typedef union
     unsigned long long int __wakeup_seq;
     unsigned long long int __woken_seq;
     void *__mutex;
-    int __clock;
+    int __nwaiters;
     unsigned int __broadcast_seq;
   } __data;
   char __size[__SIZEOF_PTHREAD_COND_T];
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
index 95f8aabd11..67bec6caa7 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
@@ -111,6 +111,7 @@ __pthread_cond_timedwait:
 	movq	8(%rsp), %rdi
 	incq	total_seq(%rdi)
 	incl	cond_futex(%rdi)
+	addl	$(1 << clock_bits), cond_nwaiters(%rdi)
 
 	/* Install cancellation handler.  */
 #ifdef PIC
@@ -135,8 +136,9 @@ __pthread_cond_timedwait:
 	/* Get the clock number.  Note that the field in the condvar
 	   structure stores the number minus 1.  */
 	movq	8(%rsp), %rdi
-	movl	cond_clock(%rdi), %edi
-	/* Only clocks 0 and 1 are allowed.  Both are handled in the
+	movl	cond_nwaiters(%rdi), %edi
+	andl	$((1 << clock_bits) - 1), %edi
+	/* Only clocks 0 and 1 are allowed so far.  Both are handled in the
 	   kernel.  */
 	leaq	24(%rsp), %rsi
 	movq	$__NR_clock_gettime, %rax
@@ -244,7 +246,23 @@ __pthread_cond_timedwait:
 9:	xorq	%r14, %r14
 14:	incq	woken_seq(%rdi)
 
-24:	LOCK
+24:	subl	$(1 << clock_bits), cond_nwaiters(%rdi)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	cmpq	$0xffffffffffffffff, total_seq(%rdi)
+	jne	25f
+	movl	cond_nwaiters(%rdi), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	25f
+
+	addq	$cond_nwaiters, %rdi
+	movq	$SYS_futex, %rax
+	movq	$FUTEX_WAKE, %rsi
+	movl	$1, %edx
+	syscall
+	subq	$cond_nwaiters, %rdi
+
+25:	LOCK
 #if cond_lock == 0
 	decl	(%rdi)
 #else
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
index 9e7da301d3..f5de0a280c 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
@@ -40,6 +40,8 @@
 	.globl	__condvar_cleanup
 	.hidden	__condvar_cleanup
 __condvar_cleanup:
+	pushq	%r12
+
 	/* Get internal lock.  */
 	movq	%rdi, %r8
 	movq	8(%rdi), %rdi
@@ -66,12 +68,28 @@ __condvar_cleanup:
 	jne	3f
 
 	incq	wakeup_seq(%rdi)
-
 	incq	woken_seq(%rdi)
-
 	incl	cond_futex(%rdi)
 
-3:	LOCK
+3:	subl	$(1 << clock_bits), cond_nwaiters(%rdi)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	xorq	%r12, %r12
+	cmpq	$0xffffffffffffffff, total_seq(%rdi)
+	jne	4f
+	movl	cond_nwaiters(%rdi), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	4f
+
+	addq	$cond_nwaiters, %rdi
+	movq	$SYS_futex, %rax
+	movq	$FUTEX_WAKE, %rsi
+	movl	$1, %edx
+	syscall
+	subq	$cond_nwaiters, %rdi
+	movq	$1, %r12
+
+4:	LOCK
 #if cond_lock == 0
 	decl	(%rdi)
 #else
@@ -84,15 +102,19 @@ __condvar_cleanup:
 	callq	__lll_mutex_unlock_wake
 
 	/* Wake up all waiters to make sure no signal gets lost.  */
-2:	addq	$cond_futex, %rdi
+2:	testq	%r12, %r12
+	jnz	5f
+	addq	$cond_futex, %rdi
 	movq	$FUTEX_WAKE, %rsi
 	movl	$0x7fffffff, %edx
 	movq	$SYS_futex, %rax
 	syscall
 
-	movq	16(%r8), %rdi
+5:	movq	16(%r8), %rdi
 	callq	__pthread_mutex_cond_lock
 
+	popq	%r12
+
 	retq
 	.size	__condvar_cleanup, .-__condvar_cleanup
 
@@ -157,6 +179,7 @@ __pthread_cond_wait:
 	movq	8(%rsp), %rdi
 	incq	total_seq(%rdi)
 	incl	cond_futex(%rdi)
+	addl	$(1 << clock_bits), cond_nwaiters(%rdi)
 
 	/* Install cancellation handler.  */
 #ifdef PIC
@@ -229,7 +252,23 @@ __pthread_cond_wait:
 	incq	woken_seq(%rdi)
 
 	/* Unlock */
-16:	LOCK
+16:	subl	$(1 << clock_bits), cond_nwaiters(%rdi)
+
+	/* Wake up a thread which wants to destroy the condvar object.  */
+	cmpq	$0xffffffffffffffff, total_seq(%rdi)
+	jne	17f
+	movl	cond_nwaiters(%rdi), %eax
+	andl	$~((1 << clock_bits) - 1), %eax
+	jne	17f
+
+	addq	$cond_nwaiters, %rdi
+	movq	$SYS_futex, %rax
+	movq	$FUTEX_WAKE, %rsi
+	movl	$1, %edx
+	syscall
+	subq	$cond_nwaiters, %rdi
+
+17:	LOCK
 #if cond_lock == 0
 	decl	(%rdi)
 #else
diff --git a/nptl/tst-cond20.c b/nptl/tst-cond20.c
new file mode 100644
index 0000000000..ba50d58534
--- /dev/null
+++ b/nptl/tst-cond20.c
@@ -0,0 +1,170 @@
+/* Copyright (C) 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>, 2004.
+
+   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 <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define N 10
+#define ROUNDS 1000
+static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+static pthread_cond_t cond2 = PTHREAD_COND_INITIALIZER;
+static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
+static pthread_barrier_t b;
+static int count;
+
+static void *
+tf (void *p)
+{
+  int i;
+  for (i = 0; i < ROUNDS; ++i)
+    {
+      pthread_mutex_lock (&mut);
+
+      if (++count == N)
+	pthread_cond_signal (&cond2);
+
+#ifdef TIMED
+      struct timeval tv;
+      gettimeofday (&tv, NULL);
+      struct timespec ts;
+      /* Wait three second.  */
+      ts.tv_sec = tv.tv_sec + 3;
+      ts.tv_nsec = tv.tv_usec * 1000;
+      pthread_cond_timedwait (&cond, &mut, &ts);
+#else
+      pthread_cond_wait (&cond, &mut);
+#endif
+
+      pthread_mutex_unlock (&mut);
+
+      int err = pthread_barrier_wait (&b);
+      if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
+	{
+	  puts ("child: barrier_wait failed");
+	  exit (1);
+	}
+
+      err = pthread_barrier_wait (&b);
+      if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
+	{
+	  puts ("child: barrier_wait failed");
+	  exit (1);
+	}
+    }
+
+  return NULL;
+}
+
+
+static int
+do_test (void)
+{
+  if (pthread_barrier_init (&b, NULL, N + 1) != 0)
+    {
+      puts ("barrier_init failed");
+      return 1;
+    }
+
+  pthread_mutex_lock (&mut);
+
+  int i, j, err;
+  pthread_t th[N];
+  for (i = 0; i < N; ++i)
+    if ((err = pthread_create (&th[i], NULL, tf, NULL)) != 0)
+      {
+	printf ("cannot create thread %d: %s\n", i, strerror (err));
+	return 1;
+      }
+
+  for (i = 0; i < ROUNDS; ++i)
+    {
+      pthread_cond_wait (&cond2, &mut);
+
+      if (i & 1)
+        pthread_mutex_unlock (&mut);
+
+      if (i & 2)
+	pthread_cond_broadcast (&cond);
+      else if (i & 4)
+	for (j = 0; j < N; ++j)
+	  pthread_cond_signal (&cond);
+      else
+	{
+	  for (j = 0; j < (i / 8) % N; ++j)
+	    pthread_cond_signal (&cond);
+	  pthread_cond_broadcast (&cond);
+	}
+
+      if ((i & 1) == 0)
+        pthread_mutex_unlock (&mut);
+
+      err = pthread_cond_destroy (&cond);
+      if (err)
+	{
+	  printf ("pthread_cond_destroy failed: %s\n", strerror (err));
+	  return 1;
+	}
+
+      /* Now clobber the cond variable which has been successfully
+         destroyed above.  */
+      memset (&cond, (char) i, sizeof (cond));
+
+      err = pthread_barrier_wait (&b);
+      if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
+	{
+	  puts ("parent: barrier_wait failed");
+	  return 1;
+	}
+
+      pthread_mutex_lock (&mut);
+
+      err = pthread_barrier_wait (&b);
+      if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
+	{
+	  puts ("parent: barrier_wait failed");
+	  return 1;
+	}
+
+      count = 0;
+      err = pthread_cond_init (&cond, NULL);
+      if (err)
+	{
+	  printf ("pthread_cond_init failed: %s\n", strerror (err));
+	  return 1;
+	}
+    }
+
+  for (i = 0; i < N; ++i)
+    if ((err = pthread_join (th[i], NULL)) != 0)
+      {
+	printf ("failed to join thread %d: %s\n", i, strerror (err));
+	return 1;
+      }
+
+  puts ("done");
+
+  return 0;
+}
+
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/nptl/tst-cond21.c b/nptl/tst-cond21.c
new file mode 100644
index 0000000000..89cb771b57
--- /dev/null
+++ b/nptl/tst-cond21.c
@@ -0,0 +1,3 @@
+#include <sys/time.h>
+#define TIMED 1
+#include "tst-cond20.c"