* sysdeps/unix/sysv/linux/powerpc/lowlevellock.h (FUTEX_WAKE_OP,

	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(lll_futex_wake_unlock): Define.
	* sysdeps/unix/sysv/linux/alpha/lowlevellock.h (FUTEX_WAKE_OP,
	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(lll_futex_wake_unlock): Define.
	* sysdeps/unix/sysv/linux/ia64/lowlevellock.h (FUTEX_WAKE_OP,
	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(lll_futex_wake_unlock): Define.
	* sysdeps/unix/sysv/linux/s390/lowlevellock.h (FUTEX_WAKE_OP,
	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(lll_futex_wake_unlock): Define.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (FUTEX_WAKE_OP,
	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(lll_futex_wake_unlock): Define.
	* sysdeps/pthread/pthread_cond_signal.c (__pthread_cond_signal): Use
	lll_futex_wake_unlock.
	* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S
	(FUTEX_WAKE_OP, FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(__pthread_cond_signal): Use FUTEX_WAKE_OP.
	* sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
	(FUTEX_WAKE_OP, FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
	(__pthread_cond_signal): Use FUTEX_WAKE_OP.

9 files changed, 171 insertions, 14 deletions

diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index b6d66d87bb..d728d92316 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,29 @@
+2005-08-29  Jakub Jelinek  <jakub@redhat.com>
+
+	* sysdeps/unix/sysv/linux/powerpc/lowlevellock.h (FUTEX_WAKE_OP,
+	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(lll_futex_wake_unlock): Define.
+	* sysdeps/unix/sysv/linux/alpha/lowlevellock.h (FUTEX_WAKE_OP,
+	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(lll_futex_wake_unlock): Define.
+	* sysdeps/unix/sysv/linux/ia64/lowlevellock.h (FUTEX_WAKE_OP,
+	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(lll_futex_wake_unlock): Define.
+	* sysdeps/unix/sysv/linux/s390/lowlevellock.h (FUTEX_WAKE_OP,
+	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(lll_futex_wake_unlock): Define.
+	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (FUTEX_WAKE_OP,
+	FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(lll_futex_wake_unlock): Define.
+	* sysdeps/pthread/pthread_cond_signal.c (__pthread_cond_signal): Use
+	lll_futex_wake_unlock.
+	* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S
+	(FUTEX_WAKE_OP, FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(__pthread_cond_signal): Use FUTEX_WAKE_OP.
+	* sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
+	(FUTEX_WAKE_OP, FUTEX_OP_CLEAR_WAKE_IF_GT_ONE): Define.
+	(__pthread_cond_signal): Use FUTEX_WAKE_OP.
+
 2005-08-23  Ulrich Drepper  <drepper@redhat.com>
 
 	* sysdeps/unix/sysv/linux/timer_routines.c (timer_helper_thread):
diff --git a/nptl/sysdeps/pthread/pthread_cond_signal.c b/nptl/sysdeps/pthread/pthread_cond_signal.c
index f5623480f8..5a9bbcad91 100644
--- a/nptl/sysdeps/pthread/pthread_cond_signal.c
+++ b/nptl/sysdeps/pthread/pthread_cond_signal.c
@@ -43,6 +43,11 @@ __pthread_cond_signal (cond)
       ++cond->__data.__futex;
 
       /* Wake one.  */
+      if (! __builtin_expect (lll_futex_wake_unlock (&cond->__data.__futex, 1,
+						     1, &cond->__data.__lock),
+						     0))
+	return 0;
+
       lll_futex_wake (&cond->__data.__futex, 1);
     }
 
diff --git a/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h
index fd4a7ca4bb..ab325d2b06 100644
--- a/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h
@@ -31,6 +31,8 @@
 #define FUTEX_WAKE		1
 #define FUTEX_REQUEUE		3
 #define FUTEX_CMP_REQUEUE	4
+#define FUTEX_WAKE_OP		5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 /* Initializer for compatibility lock.	*/
 #define LLL_MUTEX_LOCK_INITIALIZER (0)
@@ -73,6 +75,20 @@
     INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
   })
 
+/* Returns non-zero if error happened, zero if success.  */
+#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) \
+  ({									      \
+    INTERNAL_SYSCALL_DECL (__err);					      \
+    long int __ret;							      \
+    __ret = INTERNAL_SYSCALL (futex, __err, 6,				      \
+			      (futexp), FUTEX_WAKE_OP, (nr_wake),	      \
+			      (nr_wake2), (futexp2),			      \
+			      FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);		      \
+    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
+  })
+
+
+
 
 static inline int __attribute__((always_inline))
 __lll_mutex_trylock(int *futex)
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S
index 3c5a1db59c..d0f931ff15 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S
+++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_signal.S
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -31,7 +31,9 @@
 #define SYS_futex		240
 #define FUTEX_WAIT		0
 #define FUTEX_WAKE		1
-#define FUTEX_REQUEUE		3
+#define FUTEX_WAKE_OP		5
+
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 #define EINVAL			22
 
@@ -79,21 +81,46 @@ __pthread_cond_signal:
 	addl	$1, (%ebx)
 
 	/* Wake up one thread.  */
-	movl	$FUTEX_WAKE, %ecx
+	pushl	%esi
+	pushl	%ebp
+	movl	$FUTEX_WAKE_OP, %ecx
 	movl	$SYS_futex, %eax
 	movl	$1, %edx
+	movl	$1, %esi
+	movl	$FUTEX_OP_CLEAR_WAKE_IF_GT_ONE, %ebp
+	/* FIXME: Until Ingo fixes 4G/4G vDSO, 6 arg syscalls are broken for
+	   sysenter.
+	ENTER_KERNEL  */
+	int	$0x80
+	popl	%ebp
+	popl	%esi
+
+	/* For any kind of error, we try again with WAKE.
+	   The general test also covers running on old kernels.  */
+	cmpl	$-4095, %eax
+	jae	7f
+
+6:	xorl	%eax, %eax
+	popl	%edi
+	popl	%ebx
+	ret
+
+7:	movl	$FUTEX_WAKE, %ecx
+	movl	$SYS_futex, %eax
+	/* %edx should be 1 already from $FUTEX_WAKE_OP syscall.
+	movl	$1, %edx  */
 	ENTER_KERNEL
 
 	/* Unlock.  Note that at this point %edi always points to
 	   cond_lock.  */
 4:	LOCK
 	subl	$1, (%edi)
-	jne	5f
+	je	6b
 
-6:	xorl	%eax, %eax
-	popl	%edi
-	popl	%ebx
-	ret
+	/* Unlock in loop requires wakeup.  */
+5:	movl	%edi, %eax
+	call	__lll_mutex_unlock_wake
+	jmp	6b
 
 	/* Initial locking failed.  */
 1:
@@ -105,10 +132,6 @@ __pthread_cond_signal:
 	call	__lll_mutex_lock_wait
 	jmp	2b
 
-	/* Unlock in loop requires wakeup.  */
-5:	movl	%edi, %eax
-	call	__lll_mutex_unlock_wake
-	jmp	6b
 	.size	__pthread_cond_signal, .-__pthread_cond_signal
 versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,
 		  GLIBC_2_3_2)
diff --git a/nptl/sysdeps/unix/sysv/linux/ia64/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/ia64/lowlevellock.h
index e13358ffef..4219fe2716 100644
--- a/nptl/sysdeps/unix/sysv/linux/ia64/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/ia64/lowlevellock.h
@@ -31,6 +31,8 @@
 #define FUTEX_WAKE		1
 #define FUTEX_REQUEUE		3
 #define FUTEX_CMP_REQUEUE	4
+#define FUTEX_WAKE_OP		5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 /* Delay in spinlock loop.  */
 #define BUSY_WAIT_NOP          asm ("hint @pause")
@@ -62,6 +64,15 @@
    _r10 == -1;								     \
 })
 
+/* Returns non-zero if error happened, zero if success.  */
+#define lll_futex_wake_unlock(ftx, nr_wake, nr_wake2, ftx2)		     \
+({									     \
+   DO_INLINE_SYSCALL(futex, 6, (long) (ftx), FUTEX_WAKE_OP,		     \
+		     (int) (nr_wake), (int) (nr_wake2), (long) (ftx2),	     \
+		     FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);			     \
+   _r10 == -1;								     \
+})
+
 
 #define __lll_mutex_trylock(futex) \
   (atomic_compare_and_exchange_val_acq (futex, 1, 0) != 0)
diff --git a/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
index 1f2f481d64..f9eaa11e98 100644
--- a/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
@@ -33,6 +33,8 @@
 #define FUTEX_WAKE		1
 #define FUTEX_REQUEUE		3
 #define FUTEX_CMP_REQUEUE	4
+#define FUTEX_WAKE_OP		5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 /* Initializer for compatibility lock.	*/
 #define LLL_MUTEX_LOCK_INITIALIZER (0)
@@ -79,6 +81,19 @@
     INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
   })
 
+/* Returns non-zero if error happened, zero if success.  */
+#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) \
+  ({									      \
+    INTERNAL_SYSCALL_DECL (__err);					      \
+    long int __ret;							      \
+									      \
+    __ret = INTERNAL_SYSCALL (futex, __err, 6,				      \
+			      (futexp), FUTEX_WAKE_OP, (nr_wake),	      \
+			      (nr_wake2), (futexp2),			      \
+			      FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);		      \
+    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
+  })
+
 #ifdef UP
 # define __lll_acq_instr	""
 # define __lll_rel_instr	""
diff --git a/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h
index f4ed98a503..5f20537943 100644
--- a/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h
@@ -30,6 +30,8 @@
 #define FUTEX_WAKE		1
 #define FUTEX_REQUEUE		3
 #define FUTEX_CMP_REQUEUE	4
+#define FUTEX_WAKE_OP		5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 /* Initializer for compatibility lock.	*/
 #define LLL_MUTEX_LOCK_INITIALIZER (0)
@@ -103,6 +105,27 @@
   })
 
 
+/* Returns non-zero if error happened, zero if success.  */
+#define lll_futex_wake_unlock(futex, nr_wake, nr_wake2, futex2) \
+  ({									      \
+    register unsigned long int __r2 asm ("2") = (unsigned long int) (futex);  \
+    register unsigned long int __r3 asm ("3") = FUTEX_WAKE_OP;	      \
+    register unsigned long int __r4 asm ("4") = (long int) (nr_wake);	      \
+    register unsigned long int __r5 asm ("5") = (long int) (nr_wake2);	      \
+    register unsigned long int __r6 asm ("6") = (unsigned long int) (futex2); \
+    register unsigned long int __r7 asm ("7")				      \
+      = (int) FUTEX_OP_CLEAR_WAKE_IF_GT_ONE;				      \
+    register unsigned long __result asm ("2");				      \
+									      \
+    __asm __volatile ("svc %b1"						      \
+		      : "=d" (__result)					      \
+		      : "i" (SYS_futex), "0" (__r2), "d" (__r3),	      \
+			"d" (__r4), "d" (__r5), "d" (__r6), "d" (__r7)	      \
+		      : "cc", "memory" );				      \
+    __result > -4096UL;							      \
+  })
+
+
 #define lll_compare_and_swap(futex, oldval, newval, operation) \
   do {									      \
     __typeof (futex) __futex = (futex);					      \
diff --git a/nptl/sysdeps/unix/sysv/linux/sparc/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/sparc/lowlevellock.h
index 4626aec524..8d12db3a16 100644
--- a/nptl/sysdeps/unix/sysv/linux/sparc/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/sparc/lowlevellock.h
@@ -30,6 +30,8 @@
 #define FUTEX_WAKE		1
 #define FUTEX_REQUEUE		3
 #define FUTEX_CMP_REQUEUE	4
+#define FUTEX_WAKE_OP		5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 /* Initializer for compatibility lock.	*/
 #define LLL_MUTEX_LOCK_INITIALIZER (0)
@@ -76,6 +78,19 @@
     INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
   })
 
+/* Returns non-zero if error happened, zero if success.  */
+#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) \
+  ({									      \
+    INTERNAL_SYSCALL_DECL (__err);					      \
+    long int __ret;							      \
+									      \
+    __ret = INTERNAL_SYSCALL (futex, __err, 6,				      \
+			      (futexp), FUTEX_WAKE_OP, (nr_wake),	      \
+			      (nr_wake2), (futexp2),			      \
+			      FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);		      \
+    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
+  })
+
 #ifdef __sparc32_atomic_do_lock
 #error SPARC < v9 does not support compare and swap which is essential for futex based locking
 #endif
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
index de9e109f45..3dbb9e81e3 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
@@ -31,7 +31,9 @@
 #define SYS_futex		202
 #define FUTEX_WAIT		0
 #define FUTEX_WAKE		1
-#define FUTEX_REQUEUE		3
+#define FUTEX_WAKE_OP		5
+
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
 
 #define EINVAL			22
 
@@ -66,9 +68,30 @@ __pthread_cond_signal:
 	addl	$1, (%rdi)
 
 	/* Wake up one thread.  */
-	movl	$FUTEX_WAKE, %esi
+	movl	$FUTEX_WAKE_OP, %esi
 	movl	$SYS_futex, %eax
 	movl	$1, %edx
+	movl	$1, %r10d
+#if cond_lock != 0
+	addq	$cond_lock, %r8
+#endif
+	movl	$FUTEX_OP_CLEAR_WAKE_IF_GT_ONE, %r9d
+	syscall
+#if cond_lock != 0
+	subq	$cond_lock, %r8
+#endif
+	/* For any kind of error, we try again with WAKE.
+	   The general test also covers running on old kernels.  */
+	cmpq	$-4095, %rax
+	jae	7f
+
+	xorl	%eax, %eax
+	retq
+
+7:	movl	$FUTEX_WAKE, %esi
+	movl	$SYS_futex, %eax
+	/* %rdx should be 1 already from $FUTEX_WAKE_OP syscall.
+	movl	$1, %edx  */
 	syscall
 
 	/* Unlock.  */