* 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.
2005-09-08 17:41:56 +00:00 · 2005-09-08 17:41:56 +00:00 · a3615024b9
commit a3615024b9
parent b9b8cf0366
4 changed files with 91 additions and 14 deletions
--- 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.
+
 2005-09-05  Kaz Kojima  <kkojima@rr.iij4u.or.jp>

 	* sysdeps/unix/sysv/linux/sh/lowlevellock.S (__lll_mutex_lock_wait):
--- 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);
    }

--- 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)
--- 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.  */