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pthreads/pthread_rwlock.c /dev/null Libc-825.26
--- /dev/null
+++ Libc/Libc-825.26/pthreads/pthread_rwlock.c
@@ -0,0 +1,1880 @@
+/*
+ * Copyright (c) 2000-2003, 2007, 2008 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+/*-
+ * Copyright (c) 1998 Alex Nash
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD: src/lib/libc_r/uthread/uthread_rwlock.c,v 1.6 2001/04/10 04:19:20 deischen Exp $
+ */
+
+/* 
+ * POSIX Pthread Library 
+ * -- Read Write Lock support
+ * 4/24/02: A. Ramesh
+ *	   Ported from FreeBSD
+ */
+
+#include "pthread_internals.h"
+#include <stdio.h>      /* For printf(). */
+
+extern int __unix_conforming;
+
+#ifdef PLOCKSTAT
+#include "plockstat.h"
+#else /* !PLOCKSTAT */
+#define PLOCKSTAT_RW_ERROR(x, y, z)
+#define PLOCKSTAT_RW_BLOCK(x, y)
+#define PLOCKSTAT_RW_BLOCKED(x, y, z)
+#define PLOCKSTAT_RW_ACQUIRE(x, y)    
+#define PLOCKSTAT_RW_RELEASE(x, y)
+#endif /* PLOCKSTAT */
+
+#define READ_LOCK_PLOCKSTAT  0
+#define WRITE_LOCK_PLOCKSTAT 1
+
+#define BLOCK_FAIL_PLOCKSTAT    0
+#define BLOCK_SUCCESS_PLOCKSTAT 1
+
+/* maximum number of times a read lock may be obtained */
+#define	MAX_READ_LOCKS		(INT_MAX - 1) 
+
+
+#ifndef BUILDING_VARIANT /* [ */
+__private_extern__ int usenew_impl = 1;
+#else /* BUILDING_VARIANT */
+extern int usenew_impl;
+#endif /* BUILDING_VARIANT */
+
+extern int PR_5243343_flag;
+
+#if defined(__LP64__)
+#define RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr) \
+{ \
+                if (rwlock->misalign != 0) { \
+                        lcntaddr = &rwlock->rw_seq[1]; \
+			seqaddr = &rwlock->rw_seq[2]; \
+                        ucntaddr = &rwlock->rw_seq[3]; \
+                 } else { \
+                        lcntaddr = &rwlock->rw_seq[0]; \
+			seqaddr = &rwlock->rw_seq[1]; \
+                        ucntaddr = &rwlock->rw_seq[2]; \
+                } \
+}
+#else /* __LP64__ */
+#define RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr) \
+{ \
+                if (rwlock->misalign != 0) { \
+                        lcntaddr = &rwlock->rw_seq[1]; \
+			seqaddr = &rwlock->rw_seq[2]; \
+                        ucntaddr = &rwlock->rw_seq[3]; \
+                 } else { \
+                        lcntaddr = &rwlock->rw_seq[0]; \
+			seqaddr = &rwlock->rw_seq[1]; \
+                        ucntaddr = &rwlock->rw_seq[2]; \
+                } \
+}
+#endif /* __LP64__ */
+
+__private_extern__ int __pthread_rwlock_init(pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr);
+
+
+#define _KSYN_TRACE_ 0
+
+#if _KSYN_TRACE_
+#include <sys/sysctl.h>
+#ifndef BUILDING_VARIANT /* [ */
+static void set_enable(int);
+#endif /* !BUILDING_VARIANT ] */
+
+/* The Function qualifiers  */
+#define DBG_FUNC_START          1
+#define DBG_FUNC_END            2
+#define DBG_FUNC_NONE           0
+
+int __kdebug_trace(uint32_t, uint32_t, uint32_t, uint32_t, uint32_t, uint32_t);
+
+#define _KSYN_TRACE_RW_RDLOCK     0x9000080
+#define _KSYN_TRACE_RW_WRLOCK	 0x9000084
+#define _KSYN_TRACE_RW_UNLOCK    0x9000088
+#define _KSYN_TRACE_RW_UNACT1    0x900808c
+#define _KSYN_TRACE_RW_UNACT2    0x9008090
+#define _KSYN_TRACE_RW_UNACTK    0x9008094
+#define _KSYN_TRACE_RW_UNACTE    0x9008098
+#define _KSYN_TRACE_RW_UNACTR    0x900809c
+#define _KSYN_TRACE_RW_TOOMANY    0x90080a0
+#define _KSYN_TRACE_RW_TRYWRLOCK    0x90080a4
+#define _KSYN_TRACE_RW_TRYRDLOCK    0x90080a8
+#endif /* _KSYN_TRACE_ */
+
+__private_extern__ void rwlock_action_onreturn(pthread_rwlock_t * rwlock, uint32_t updateval);
+__private_extern__ int rw_diffgenseq(uint32_t x, uint32_t y);
+
+#ifndef BUILDING_VARIANT /* [ */
+static uint32_t modbits(uint32_t lgenval, uint32_t updateval, uint32_t savebits);
+
+int
+pthread_rwlockattr_init(pthread_rwlockattr_t *attr)
+{
+        attr->sig = _PTHREAD_RWLOCK_ATTR_SIG;
+	attr->pshared = _PTHREAD_DEFAULT_PSHARED;
+        return (0);
+}
+
+int       
+pthread_rwlockattr_destroy(pthread_rwlockattr_t *attr)
+{
+        attr->sig = _PTHREAD_NO_SIG;  /* Uninitialized */
+	attr->pshared = 0;
+        return (0);
+}
+
+int
+pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *attr,
+				int *pshared)
+{
+        if (attr->sig == _PTHREAD_RWLOCK_ATTR_SIG)
+        {
+		*pshared = (int)attr->pshared; 
+                return (0);
+        } else
+        {
+                return (EINVAL); /* Not an initialized 'attribute' structure */
+        }
+}
+
+
+int
+pthread_rwlockattr_setpshared(pthread_rwlockattr_t * attr, int pshared)
+{
+        if (attr->sig == _PTHREAD_RWLOCK_ATTR_SIG)
+        {
+#if __DARWIN_UNIX03
+                if (( pshared == PTHREAD_PROCESS_PRIVATE) || (pshared == PTHREAD_PROCESS_SHARED))
+#else /* __DARWIN_UNIX03 */
+                if ( pshared == PTHREAD_PROCESS_PRIVATE)
+#endif /* __DARWIN_UNIX03 */
+                {
+						attr->pshared = pshared ;
+                        return (0);
+                } else
+                {
+                        return (EINVAL); /* Invalid parameter */
+                }
+        } else
+        {
+                return (EINVAL); /* Not an initialized 'attribute' structure */
+        }
+
+}
+
+__private_extern__ int
+__pthread_rwlock_init(pthread_rwlock_t * orwlock, const pthread_rwlockattr_t *attr)
+{
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+
+	if ((attr != NULL) && (attr->pshared == PTHREAD_PROCESS_SHARED)) {
+		rwlock->pshared = PTHREAD_PROCESS_SHARED;
+		rwlock->rw_flags = PTHRW_KERN_PROCESS_SHARED;
+	 } else {
+		rwlock->pshared = _PTHREAD_DEFAULT_PSHARED;
+		rwlock->rw_flags = PTHRW_KERN_PROCESS_PRIVATE;
+	}
+	
+	if (((uintptr_t)rwlock & 0x07) != 0) {
+		rwlock->misalign = 1;
+#if defined(__LP64__)
+		rwlock->rw_lcntaddr = &rwlock->rw_seq[1];
+		rwlock->rw_seqaddr = &rwlock->rw_seq[2];
+		rwlock->rw_ucntaddr = &rwlock->rw_seq[3];
+		rwlock->rw_seq[1]= PTHRW_RWLOCK_INIT;
+		rwlock->rw_seq[2]= PTHRW_RWS_INIT;
+		rwlock->rw_seq[3]= 0;
+#else /* __LP64__ */
+		rwlock->rw_lcntaddr = &rwlock->rw_seq[1];
+		rwlock->rw_seqaddr = &rwlock->rw_seq[2];
+		rwlock->rw_ucntaddr = &rwlock->rw_seq[3];
+		rwlock->rw_seq[1]= PTHRW_RWLOCK_INIT;
+		rwlock->rw_seq[2]= PTHRW_RWS_INIT;
+		rwlock->rw_seq[3]= 0;
+#endif /* __LP64__ */
+		
+	} else {
+		rwlock->misalign = 0;
+#if defined(__LP64__)
+		rwlock->rw_lcntaddr = &rwlock->rw_seq[0];
+		rwlock->rw_seqaddr = &rwlock->rw_seq[1];
+		rwlock->rw_ucntaddr = &rwlock->rw_seq[2];
+		rwlock->rw_seq[0]= PTHRW_RWLOCK_INIT;
+		rwlock->rw_seq[1]= PTHRW_RWS_INIT;
+		rwlock->rw_seq[2]= 0;
+#else /* __LP64__ */
+		rwlock->rw_lcntaddr = &rwlock->rw_seq[0];
+		rwlock->rw_seqaddr = &rwlock->rw_seq[1];
+		rwlock->rw_ucntaddr = &rwlock->rw_seq[2];
+		rwlock->rw_seq[0]= PTHRW_RWLOCK_INIT;
+		rwlock->rw_seq[1]= PTHRW_RWS_INIT;
+		rwlock->rw_seq[2]= 0;
+#endif /* __LP64__ */
+		
+	}
+
+	rwlock->reserv = 0;
+	rwlock->rw_owner = NULL;
+#if defined(__LP64__)
+	memset(rwlock->rfu, 0, PTHRW_RFU_64BIT);
+#else
+	memset(rwlock->rfu, 0, PTHRW_RFU_32BIT);
+#endif 
+
+	rwlock->sig = _PTHREAD_RWLOCK_SIG;
+	
+	return(0);
+}
+
+#if _KSYN_TRACE_
+static void
+set_enable(int val)
+{
+	int mib[6];
+	size_t needed = 0;
+
+    mib[0] = CTL_KERN;
+	mib[1] = KERN_KDEBUG;
+	mib[2] = KERN_KDENABLE;
+	mib[3] = val;
+	mib[4] = 0;
+	mib[5] = 0;
+	/* best effort to stop the trace */
+	(void)sysctl(mib, 4, NULL, &needed, NULL, 0);
+}
+#endif
+
+static uint32_t
+modbits(uint32_t lgenval, uint32_t updateval, uint32_t savebits)
+{
+	uint32_t lval = lgenval & PTHRW_BIT_MASK;
+	uint32_t uval = updateval & PTHRW_BIT_MASK;
+	uint32_t rval, nlval;
+
+	nlval = (lval | uval) & ~(PTH_RWL_MBIT);
+	
+	/* reconcile bits on the lock with what kernel needs to set */
+	if ((uval & PTH_RWL_LBIT) != 0)
+		nlval &= ~PTH_RWL_KBIT;
+	else if (((uval & PTH_RWL_KBIT) == 0) && ((lval & PTH_RWL_WBIT) == 0))
+		nlval &= ~PTH_RWL_KBIT;
+
+	if (savebits !=0 ) {
+		if (((savebits & PTH_RWS_WSVBIT) != 0) && ((nlval & PTH_RWL_WBIT) == 0) && 
+				((nlval & PTH_RWL_EBIT) == 0)) {
+			if ((nlval & PTH_RWL_LBIT) == 0)
+				nlval |= (PTH_RWL_WBIT | PTH_RWL_KBIT);
+			else
+				nlval |= PTH_RWL_WBIT;
+		}
+		if (((savebits & PTH_RWS_YSVBIT) != 0) && ((nlval & PTH_RWL_YBIT) == 0) && 
+				((nlval & PTH_RWL_EBIT) == 0)) {
+				nlval |= PTH_RWL_YBIT;
+		}
+		if (((savebits & PTH_RWS_USVBIT) != 0) && ((nlval & PTH_RWL_EBIT) == 0)) {
+			if ((nlval & PTH_RWL_LBIT) == 0)
+				nlval |= (PTH_RWL_UBIT | PTH_RWL_KBIT);
+			else
+				nlval |= PTH_RWL_UBIT;
+		}
+	}
+	rval = (lgenval & PTHRW_COUNT_MASK) | nlval;
+	return(rval);
+}
+
+
+__private_extern__ void
+rwlock_action_onreturn(pthread_rwlock_t * orwlock, uint32_t updateval)
+{
+
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, rw_seq, newval = 0, newsval, lval, uval;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t oldval64, newval64;
+	int setbits = 0;
+	int overlap = 0;
+	uint32_t savebits = 0;
+	int isoverlap = 0;
+	
+	/* TBD: restore U bit */
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNACT1 | DBG_FUNC_START, updateval, 0, 0, 0, 0);
+#endif
+
+	isoverlap = updateval & PTH_RWL_MBIT;
+
+loop:
+	setbits = 0;
+	lcntval = *lcntaddr;
+	rw_seq = *seqaddr;
+	savebits = 0;
+	
+	if (isoverlap != 0) {
+		/* overlap return, just increment and inspect bits */
+		setbits = 1;
+		overlap = 1;
+		/* set s word, increment by specified value  */
+		newsval = rw_seq + (updateval & PTHRW_COUNT_MASK);
+		if ((newsval &  PTHRW_RWS_SAVEMASK) != 0) {
+			savebits = newsval & PTHRW_RWS_SAVEMASK;
+			newsval &= ~PTHRW_RWS_SAVEMASK;
+		}
+	} else {
+		/* normal return */
+		if (is_rws_setunlockinit(rw_seq) != 0) {
+			setbits = 1;
+			/* set s word to passed in value */
+			newsval = (rw_seq & PTHRW_COUNT_MASK) + (updateval & PTHRW_COUNT_MASK);
+			if ((rw_seq &  PTHRW_RWS_SAVEMASK) != 0) {
+				savebits = rw_seq & PTHRW_RWS_SAVEMASK;
+				newsval &= ~PTHRW_RWS_SAVEMASK;
+			}
+		} else {
+			newval = lcntval;
+			newsval = rw_seq;
+		}
+	}
+	if (setbits != 0) {
+		newval = modbits(lcntval, updateval, savebits);
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNACT1 | DBG_FUNC_NONE, rw_seq, newsval, 0xeeeeeeee, updateval, 0);
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNACT1 | DBG_FUNC_NONE, lcntval, newval, 0xeeeeeeee, updateval, 0);
+#endif
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+			goto loop;
+		/* Check for consistency */
+		lval = lcntval & PTHRW_BIT_MASK;
+		uval = updateval & PTHRW_BIT_MASK;
+	}
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNACT1 | DBG_FUNC_END, rw_seq, newsval, 0xffffffff, 0, 0);
+#endif
+	return;
+}
+
+/* returns are not bit shifted */
+__private_extern__ int
+rw_diffgenseq(uint32_t x, uint32_t y)
+{
+	uint32_t lx = (x & PTHRW_COUNT_MASK);
+	uint32_t ly = (y &PTHRW_COUNT_MASK);
+
+	if (lx  > ly) {
+		return(lx-ly);
+	} else {
+		return((PTHRW_MAX_READERS - y) + lx + PTHRW_INC);
+	}
+
+}
+
+#ifdef NOTYET
+/********************************************************** */
+static int pthread_rwlock_upgrade_internal(pthread_rwlock_t * orwlock, int trylock);
+
+int
+pthread_rwlock_longrdlock_np(pthread_rwlock_t * orwlock)
+{
+	pthread_t self;
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0, retry_count = 0;
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+	
+	if (can_rwl_longreadinuser(lcntval))
+		goto gotlock;
+
+#if __DARWIN_UNIX03
+	if (is_rwl_ebit_set(lcntval)) {
+		self = pthread_self();
+		if(rwlock->rw_owner == self) {
+			error = EDEADLK;
+			goto out;
+		}
+	}
+#endif /* __DARWIN_UNIX03 */
+	
+	/* need to block in kernel */
+	newval  = (lcntval + PTHRW_INC);
+
+	newsval = rw_seq;
+	if (is_rws_setseq(rw_seq)) {
+		newsval &= PTHRW_SW_Reset_BIT_MASK;
+		newsval |= (newval & PTHRW_COUNT_MASK);
+	}
+
+	/* update lock seq and  block in kernel */
+	
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)(newsval)) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+kblock:
+	updateval = __psynch_rw_longrdlock(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+	
+	if (error == EINTR)
+		goto kblock;
+	
+	if (error == 0) {
+		rwlock_action_onreturn(orwlock, updateval);
+		if ( is_rwl_lbit_clear(updateval)) {
+#if _KSYN_TRACE_
+			set_enable(2);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("yieldwrlock from kernel without EBit  %x: tid %x\n", updateval, (uint32_t)myid);
+			/* kernel cannot wakeup without granting E bit */
+		}
+		goto successout;
+	} else {
+#if _KSYN_TRACE_
+		set_enable(2);
+#endif /* _KSYN_TRACE_ */
+		(void)pthread_threadid_np(pthread_self(), &myid);
+		LIBC_ABORT("yieldwrlock from kernel with unknown error %x: tid %x\n", updateval, (uint32_t)myid);
+		goto out;
+	}
+	
+gotlock:
+	if (rw_diffgenseq(lcntval, ucntval) >= PTHRW_MAX_READERS) {
+		/* since ucntval may be newer, just redo */
+		retry_count++;
+		if (retry_count > 1024) {
+		
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TOOMANY | DBG_FUNC_NONE, (uint32_t)rwlock, 0XEEEEEEEE, lcntval, ucntval, 0);
+#endif
+			error = EAGAIN;
+			goto out;
+		} else {
+			sched_yield();
+			goto loop;
+		}
+	}
+	
+	/* Need to update L and S word */
+	newval  = (lcntval + PTHRW_INC) | PTH_RWL_LBIT;
+	newsval = (rw_seq + PTHRW_INC);
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+
+successout:
+	PLOCKSTAT_RW_ACQUIRE(orwlock, READ_LOCK_PLOCKSTAT);
+	return(0);
+out:
+	PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);    
+	return(error);
+}
+
+int
+pthread_rwlock_yieldwrlock_np(pthread_rwlock_t * orwlock)
+{
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0;
+#if __DARWIN_UNIX03
+	pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+
+#if __DARWIN_UNIX03
+	if (is_rwl_ebit_set(lcntval)) {
+		if (rwlock->rw_owner == self) {
+			error = EDEADLK;
+			goto out;
+		}
+	}
+#endif /* __DARWIN_UNIX03 */
+	
+	if (lcntval == PTHRW_RWL_INIT) {
+		/* if we can acquire set L and S word */
+		lcntval = PTHRW_RWL_INIT;
+		newval  = PTHRW_RWL_INIT | PTHRW_INC | PTH_RWL_KBIT| PTH_RWL_EBIT;
+		newsval = rw_seq + PTHRW_INC;
+
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+	
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) == TRUE) {
+			goto gotit;
+		} else
+			goto loop;
+	}
+	
+	newval = (lcntval + PTHRW_INC)| PTH_RWL_YBIT;	
+
+	newsval = rw_seq;
+	if (is_rws_setseq(rw_seq)) {
+		newsval &= PTHRW_SW_Reset_BIT_MASK;
+		newsval |= (newval & PTHRW_COUNT_MASK);
+	}
+	
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)(newsval)) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+
+	PLOCKSTAT_RW_BLOCK(orwlock, WRITE_LOCK_PLOCKSTAT);
+retry:
+	updateval = __psynch_rw_yieldwrlock(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+	
+	if (error == EINTR)
+		goto retry;
+	
+	
+	PLOCKSTAT_RW_BLOCKED(orwlock, WRITE_LOCK_PLOCKSTAT, BLOCK_SUCCESS_PLOCKSTAT);
+	if (error != 0) {
+#if _KSYN_TRACE_
+		set_enable(2);
+#endif /* _KSYN_TRACE_ */
+		(void)pthread_threadid_np(pthread_self(), &myid);
+		LIBC_ABORT("yieldwrlock from kernel with unknown error %x: tid %x\n", updateval, (uint32_t)myid);
+	}
+	
+	
+out:	
+	if (error == 0) {
+gotit:
+		rwlock_action_onreturn(orwlock, updateval);
+		if ( is_rwl_ebit_clear(updateval)) {
+#if _KSYN_TRACE_
+			set_enable(2);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("yieldwrlock from kernel without EBit  %x: tid %x\n", updateval, (uint32_t)myid);
+		}
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = self;
+#endif /* __DARWIN_UNIX03 */
+		PLOCKSTAT_RW_ACQUIRE(orwlock, WRITE_LOCK_PLOCKSTAT);
+		return(0);
+	} else {
+		PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, error);    
+		return(error);
+	}
+}
+int
+pthread_rwlock_downgrade_np(pthread_rwlock_t * orwlock)
+{
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0, haswbit = 0, hasubit = 0, hasybit = 0;
+#if __DARWIN_UNIX03
+	pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+
+	
+	/* if not holding exclusive lock, return */
+	if ((is_rwl_ebit_set(lcntval )== 0) || (rwlock->rw_owner != self)) {
+		return(EINVAL);
+	}
+	
+	/* no other waiters and be granted in user space? ? */
+	if ((lcntval & PTHRW_COUNT_MASK) == (ucntval + PTHRW_INC)) {
+#if 0
+		/* should have no write waiters pending */
+		if (is_rwl_wbit_set(lcntval) != 0) {
+#if _KSYN_TRACE_
+			set_enable(2);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("downgrade in user mode but W bit set  %x: tid %x\n", lcntval, (uint32_t)myid);
+		}
+#endif
+		/* preserve count and remove ke bits */
+		newval = lcntval & ~(PTH_RWL_EBIT | PTH_RWL_KBIT);
+		/* if we can acquire set L and S word */
+		newsval = rw_seq;
+
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+	
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) == TRUE) {
+#if __DARWIN_UNIX03
+			rwlock->rw_owner = (pthread_t)0;
+#endif /* __DARWIN_UNIX03 */
+			return(0);
+		} else
+			goto loop;
+	} else {
+		
+		haswbit = lcntval & PTH_RWL_WBIT;
+		hasubit = lcntval & PTH_RWL_UBIT;
+		hasybit = lcntval & PTH_RWL_YBIT;
+
+		/* reset all bits and set k */
+		newval = (lcntval & PTHRW_COUNT_MASK) | PTH_RWL_KBIT;
+		/* set I bit on S word */	
+		newsval = rw_seq | PTH_RWS_IBIT;
+		if (haswbit != 0)
+			newsval |= PTH_RWS_WSVBIT;
+		if (hasubit != 0)
+			newsval |= PTH_RWS_USVBIT;
+		if (hasybit != 0)
+			newsval |= PTH_RWS_YSVBIT;
+
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+	
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+			goto loop;
+
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = 0;
+#endif /* __DARWIN_UNIX03 */
+
+retry:
+		updateval = __psynch_rw_downgrade(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+		if (updateval == (uint32_t)-1) {
+			error = errno;
+		} else
+			error = 0;
+	
+		/* TBD: what to do with the error, EINTR ?? */
+		if (error == EINTR)
+			goto retry;
+
+		if (error == 0)  {
+			rwlock_action_onreturn(orwlock, updateval);
+			return(0);
+		} else {
+#if _KSYN_TRACE_
+			set_enable(1);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("downgrade from kernel with unknown error %x with tid %x\n", updateval, (uint32_t)myid);
+		}
+		/* Not reached */	
+	}
+	return(EINVAL);	
+}
+
+int
+pthread_rwlock_upgrade_np(pthread_rwlock_t * orwlock)
+{
+	return(pthread_rwlock_upgrade_internal(orwlock, 0));
+}
+
+int
+pthread_rwlock_tryupgrade_np(pthread_rwlock_t *orwlock)
+{
+	return(pthread_rwlock_upgrade_internal(orwlock, 1));
+}
+
+static int
+pthread_rwlock_upgrade_internal(pthread_rwlock_t * orwlock, int trylock)
+{
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0, flags ;
+#if __DARWIN_UNIX03
+	pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		/* check for static initialization */
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+	
+	if (is_rwl_eubit_set(lcntval) !=0) {
+		return(EBUSY);
+	}
+	
+	/* set U and K bit and go to kernel */
+	newval  = (lcntval  | (PTH_RWL_UBIT | PTH_RWL_KBIT));
+	newsval = rw_seq;
+#if 0
+	if (is_rws_setseq(rw_seq)) {
+		newsval &= PTHRW_SW_Reset_BIT_MASK;
+		newsval |= (newval & PTHRW_COUNT_MASK);
+	}
+#endif
+
+	/* update lock seq and  block in kernel */
+	
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)(newsval)) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+	flags = rwlock->rw_flags;
+	if (trylock != 0) {
+		flags |= _PTHREAD_RWLOCK_UPGRADE_TRY;
+	}
+retry:
+	updateval = __psynch_rw_upgrade(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+		
+	if (error == EINTR)
+		goto retry;
+		
+		
+	if (error == 0) {
+		rwlock_action_onreturn(orwlock, updateval);
+		if ( is_rwl_ebit_clear(updateval)) {
+#if _KSYN_TRACE_
+			set_enable(2);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("upgrade from kernel without EBit  %x: tid %x\n", updateval, (uint32_t)myid);
+		}
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = self;
+#endif /* __DARWIN_UNIX03 */
+		return(0);
+	} else {
+		if (trylock != 0) {
+			return (EBUSY);
+		}
+	}
+
+	return(error);	
+}
+
+/* Returns true if the rwlock is held for reading by any thread or held for writing by the current thread */
+int 
+pthread_rwlock_held_np(pthread_rwlock_t * orwlock)
+{
+	uint32_t lcntval, ucntval, rw_seq;
+	int error = 0;
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				return(0);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			return(-1);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+	
+	if ((lcntval & PTHRW_COUNT_MASK) == (ucntval & PTHRW_COUNT_MASK))
+		return(0);
+	
+	return(1);
+}
+
+/* Returns true if the rwlock is held for reading by any thread */
+int 
+pthread_rwlock_rdheld_np(pthread_rwlock_t * orwlock)
+{
+	uint32_t lcntval, ucntval, rw_seq;
+	int error = 0;
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				return(0);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			return(-1);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+
+	if ((lcntval & PTHRW_COUNT_MASK) == (ucntval & PTHRW_COUNT_MASK))
+		return(0);
+
+	if (is_rwl_ebit_set(lcntval) !=0) {
+		return(0);
+	}
+	return(1);
+}
+
+/* Returns true if the rwlock is held for writing by the current thread */
+int 
+pthread_rwlock_wrheld_np(pthread_rwlock_t * orwlock)
+{
+	uint32_t lcntval, ucntval, rw_seq;
+	pthread_t self = pthread_self();
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	int error = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				return(0);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			return(-1);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+
+	if ((is_rwl_ebit_set(lcntval)) && (rwlock->rw_owner == self)) {
+		return(1);
+	}
+	return(0);
+}
+/******************************************************/
+#endif /* NOTYET */
+
+
+#endif /* !BUILDING_VARIANT ] */
+
+int
+pthread_rwlock_destroy(pthread_rwlock_t *orwlock)
+{
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+#if __DARWIN_UNIX03
+	uint32_t rw_lcnt, rw_ucnt;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+#endif /* __DARWIN_UNIX03 */
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG && rwlock->sig != _PTHREAD_RWLOCK_SIG_init)
+		return(EINVAL);
+	if (rwlock->sig == _PTHREAD_RWLOCK_SIG) {
+#if __DARWIN_UNIX03
+		if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+			RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+		} else {
+			lcntaddr = rwlock->rw_lcntaddr;
+			ucntaddr = rwlock->rw_ucntaddr;
+			seqaddr = rwlock->rw_seqaddr;
+		}
+
+		rw_lcnt = *lcntaddr;
+		rw_ucnt = *ucntaddr;
+		
+		if((rw_lcnt & PTHRW_COUNT_MASK) != rw_ucnt)
+			return(EBUSY);
+		
+#endif /* __DARWIN_UNIX03 */
+		//bzero(rwlock, sizeof(npthread_rwlock_t));
+		rwlock->sig = _PTHREAD_NO_SIG;
+		return(0);
+	} else if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		rwlock->sig = _PTHREAD_NO_SIG;
+                return(0);
+	} else 
+		return(EINVAL);
+}
+
+
+int
+pthread_rwlock_init(pthread_rwlock_t * orwlock, const pthread_rwlockattr_t *attr)
+{
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+#if __DARWIN_UNIX03
+	uint32_t rw_lcnt, rw_ucnt;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+#endif /* __DARWIN_UNIX03 */
+	
+#if __DARWIN_UNIX03
+	if (attr && (attr->sig != _PTHREAD_RWLOCK_ATTR_SIG)) {
+		return(EINVAL);
+	}
+	
+	if (rwlock->sig == _PTHREAD_RWLOCK_SIG) {
+		if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+			RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+		} else {
+			lcntaddr = rwlock->rw_lcntaddr;
+			ucntaddr = rwlock->rw_ucntaddr;
+			seqaddr = rwlock->rw_seqaddr;
+		}
+		
+		rw_lcnt = *lcntaddr;
+		rw_ucnt = *ucntaddr;
+		
+		if ((rw_lcnt & PTHRW_COUNT_MASK) != rw_ucnt)
+			return(EBUSY);
+		
+	}
+#endif
+	LOCK_INIT(rwlock->lock);
+	return(__pthread_rwlock_init(orwlock, attr));
+	
+}
+
+int
+pthread_rwlock_rdlock(pthread_rwlock_t * orwlock)
+{
+#if __DARWIN_UNIX03
+	pthread_t self;
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0, retry_count = 0;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_START, (uint32_t)rwlock, 0, 0, 0, 0);
+#endif
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, lcntval, (ucntval | 0xee), rw_seq, 0);
+#endif
+	
+	/* if l bit is on or u and k bit is clear, acquire lock in userland */
+	if (can_rwl_readinuser(lcntval))
+		goto gotlock;
+	
+#if __DARWIN_UNIX03
+	if (is_rwl_ebit_set(lcntval)) {
+		self = pthread_self();
+		if(rwlock->rw_owner == self) {
+			error = EDEADLK;
+			goto out;
+		}
+	}
+#endif /* __DARWIN_UNIX03 */
+	
+
+	/* Need to block in kernel , remove Rbit */
+	newval  = (lcntval + PTHRW_INC) & PTH_RWLOCK_RESET_RBIT;
+	
+	newsval = rw_seq;
+	if (is_rws_setseq(rw_seq)) {
+		newsval &= PTHRW_SW_Reset_BIT_MASK;
+		newsval |= (newval & PTHRW_COUNT_MASK);
+	}
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+
+	/* give writers priority over readers */
+	PLOCKSTAT_RW_BLOCK(orwlock, READ_LOCK_PLOCKSTAT);
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, lcntval, newval, newsval, 0);
+#endif
+
+retry:
+	updateval = __psynch_rw_rdlock(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+	
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+	
+	if (error == EINTR)
+		goto retry;
+
+	if (error == 0)  {
+		rwlock_action_onreturn(orwlock, updateval);
+		PLOCKSTAT_RW_BLOCKED(orwlock, READ_LOCK_PLOCKSTAT, BLOCK_SUCCESS_PLOCKSTAT);
+		PLOCKSTAT_RW_ACQUIRE(orwlock, READ_LOCK_PLOCKSTAT);    
+		return(0);
+	} else {
+		PLOCKSTAT_RW_BLOCKED(orwlock, READ_LOCK_PLOCKSTAT, BLOCK_FAIL_PLOCKSTAT);
+#if _KSYN_TRACE_
+		set_enable(1);
+#endif /* _KSYN_TRACE_ */
+		(void)pthread_threadid_np(pthread_self(), &myid);
+		LIBC_ABORT("rdlock from kernel with unknown error %x with tid %x\n", updateval, (uint32_t)myid);
+		goto out;
+	}
+	/* Not reached */	
+	
+gotlock:
+	if (rw_diffgenseq(lcntval, ucntval) >= PTHRW_MAX_READERS) {
+		/* since ucntval may be newer, just redo */
+		retry_count++;
+		if (retry_count > 1024) {
+		
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TOOMANY | DBG_FUNC_NONE, (uint32_t)rwlock, 0XEEEEEEEE, lcntval, ucntval, 0);
+#endif
+			error = EAGAIN;
+			goto out;
+		} else {
+			sched_yield();
+			goto loop;
+		}
+	}
+	
+	/* Need to update L (remove R bit) and S word */
+	newval  = (lcntval + PTHRW_INC)  & PTH_RWLOCK_RESET_RBIT;
+	newsval = (rw_seq + PTHRW_INC);
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555555, lcntval, newval, 0);
+#endif
+	
+	PLOCKSTAT_RW_ACQUIRE(orwlock, READ_LOCK_PLOCKSTAT);
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, 0, 0, 0);
+#endif
+	return(0);
+out:
+	PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);    
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_RDLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, error, 0, 0);
+#endif
+	return(error);
+}
+
+int
+pthread_rwlock_tryrdlock(pthread_rwlock_t * orwlock)
+{
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval;
+	int error = 0, retry_count = 0;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYRDLOCK | DBG_FUNC_START, (uint32_t)rwlock, lcntval, ucntval, rw_seq, 0);
+#endif
+
+	/* if l bit is on or u and k bit is clear, acquire lock in userland */
+	if (can_rwl_readinuser(lcntval))
+		goto gotlock;
+	
+	error = EBUSY;
+	goto out;
+	
+gotlock:
+	if (rw_diffgenseq(lcntval, ucntval) >= PTHRW_MAX_READERS) {
+		/* since ucntval may be newer, just redo */
+		retry_count++;
+		if (retry_count > 1024) {
+		
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TOOMANY | DBG_FUNC_NONE, (uint32_t)rwlock, 0XEEEEEEEE, lcntval, ucntval, 0);
+#endif
+			error = EAGAIN;
+			goto out;
+		} else {
+			sched_yield();
+			goto loop;
+		}
+	}
+	
+	/* Need to update L(remove Rbit ) and S word */
+	newval  = (lcntval + PTHRW_INC) & PTH_RWLOCK_RESET_RBIT;
+	newsval = (rw_seq + PTHRW_INC);
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYRDLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555555, lcntval, newval, 0);
+#endif
+	
+	PLOCKSTAT_RW_ACQUIRE(orwlock, READ_LOCK_PLOCKSTAT);
+	return(0);
+
+out:
+	PLOCKSTAT_RW_ERROR(orwlock, READ_LOCK_PLOCKSTAT, error);    
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYRDLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555555, error, 0, 0);
+#endif
+	return(error);
+}
+
+int
+pthread_rwlock_trywrlock(pthread_rwlock_t * orwlock)
+{
+#if __DARWIN_UNIX03
+	pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, rw_seq, newval, newsval;
+	int error = 0, gotlock = 0;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYWRLOCK | DBG_FUNC_START, (uint32_t)rwlock, 0, 0, 0, 0);
+#endif
+loop:
+	lcntval = *lcntaddr;
+	rw_seq = *seqaddr;
+
+	/* can we acquire in userland? */
+	if ((lcntval & PTH_RWL_RBIT) != 0) {
+		newval  = ((lcntval + PTHRW_INC) & PTHRW_COUNT_MASK) | PTH_RWL_IBIT | PTH_RWL_KBIT| PTH_RWL_EBIT;
+		newsval = rw_seq + PTHRW_INC;
+		gotlock = 1;
+	} else
+		gotlock = 0;
+
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	if (gotlock != 0) {
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	} else 
+		newval64 = oldval64;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE) {
+		goto loop;
+	}
+	if (gotlock == 1) {
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = self;
+#endif /* __DARWIN_UNIX03 */
+		PLOCKSTAT_RW_ACQUIRE(orwlock, WRITE_LOCK_PLOCKSTAT);
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYWRLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0, 0, 0, 0);
+#endif
+		return(0);
+	} else {
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_TRYWRLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, EBUSY, 0, 0);
+#endif
+
+		PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, EBUSY);    
+		return(EBUSY);
+	}
+}
+
+int
+pthread_rwlock_wrlock(pthread_rwlock_t * orwlock)
+{
+#if __DARWIN_UNIX03
+	pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval;
+	int error = 0, gotlock = 0;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_START, (uint32_t)rwlock, 0, 0, 0, 0);
+#endif
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, lcntval, ucntval, rw_seq, 0);
+#endif
+
+#if __DARWIN_UNIX03
+	if (is_rwl_ebit_set(lcntval)) {
+		if(rwlock->rw_owner == self) {
+			error = EDEADLK;
+			goto out;
+		}
+	}
+#endif /* __DARWIN_UNIX03 */
+
+	
+	if ((lcntval & PTH_RWL_RBIT) != 0) {
+		/* lock is restart state, writer can acquire the lock */
+		newval  = ((lcntval + PTHRW_INC) & PTHRW_COUNT_MASK) | PTH_RWL_IBIT | PTH_RWL_KBIT| PTH_RWL_EBIT;
+
+		newsval = rw_seq + PTHRW_INC;
+		gotlock = 1;
+
+	} else {
+		if (is_rwl_lbit_set(lcntval))
+			newval = (lcntval + PTHRW_INC)| PTH_RWL_WBIT;	
+		else
+			newval = (lcntval + PTHRW_INC) | PTH_RWL_KBIT| PTH_RWL_WBIT;	
+
+		newsval = rw_seq;
+		if (is_rws_setseq(rw_seq)) {
+			newsval &= PTHRW_SW_Reset_BIT_MASK;
+			newsval |= (newval & PTHRW_COUNT_MASK);
+		}
+		gotlock = 0;
+	}
+
+	/* update lock seq */
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555555, lcntval, newval, 0);
+#endif
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto loop;
+		
+	/* lock acquired in userland itself? */
+	if (gotlock != 0)
+		goto gotit;
+
+	/* unable to acquire in userland, transition to kernel */
+
+	PLOCKSTAT_RW_BLOCK(orwlock, WRITE_LOCK_PLOCKSTAT);
+retry:
+	updateval = __psynch_rw_wrlock(orwlock, newval, ucntval, newsval, rwlock->rw_flags);
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+	
+	if (error == EINTR) {
+		goto retry;
+	} 
+
+	if (error != 0) {
+#if _KSYN_TRACE_
+		set_enable(2);
+#endif /* _KSYN_TRACE_ */
+		(void)pthread_threadid_np(pthread_self(), &myid);
+		LIBC_ABORT("wrlock from kernel with unknown error %x: tid %x\n", updateval, (uint32_t)myid);
+	}
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x33333333, newval, updateval, 0);
+#endif
+	PLOCKSTAT_RW_BLOCKED(orwlock, WRITE_LOCK_PLOCKSTAT, BLOCK_SUCCESS_PLOCKSTAT);
+	if (error == 0) {
+		rwlock_action_onreturn(orwlock, updateval);
+gotit:
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = self;
+#endif /* __DARWIN_UNIX03 */
+		PLOCKSTAT_RW_ACQUIRE(orwlock, WRITE_LOCK_PLOCKSTAT);
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, error, 0, 0);
+#endif
+		return(0);
+	} 
+#if __DARWIN_UNIX03
+out:
+#endif /* __DARWIN_UNIX03 */
+	PLOCKSTAT_RW_ERROR(orwlock, WRITE_LOCK_PLOCKSTAT, error);    
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_WRLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, error, 0, 0);
+#endif
+	return(error);
+}
+
+
+int
+pthread_rwlock_unlock(pthread_rwlock_t * orwlock)
+{
+	npthread_rwlock_t * rwlock = (npthread_rwlock_t *)orwlock;
+	uint32_t lcntval, ucntval, rw_seq, newval, newsval, updateval, ulval;
+	int error = 0, wrlock = 0, haswbit = 0, hasubit = 0, hasybit = 0;
+	uint64_t oldval64, newval64;
+	volatile uint32_t * lcntaddr, *ucntaddr, *seqaddr;
+	uint64_t myid = 0;
+	
+	if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+		LOCK(rwlock->lock);
+		if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+		 	if ((error = __pthread_rwlock_init(orwlock, NULL)) != 0)  {
+				UNLOCK(rwlock->lock);
+				PLOCKSTAT_RW_ERROR(orwlock, wrlock, error);
+				return(error);
+			}
+		} else if (rwlock->sig != _PTHREAD_RWLOCK_SIG){
+			UNLOCK(rwlock->lock);
+			PLOCKSTAT_RW_ERROR(orwlock, wrlock, EINVAL);
+			return(EINVAL);
+		}
+		UNLOCK(rwlock->lock);
+	}
+	
+	if (rwlock->pshared == PTHREAD_PROCESS_SHARED) {
+		RWLOCK_GETSEQ_ADDR(rwlock, lcntaddr, ucntaddr, seqaddr);
+	} else {
+		lcntaddr = rwlock->rw_lcntaddr;
+		ucntaddr = rwlock->rw_ucntaddr;
+		seqaddr = rwlock->rw_seqaddr;
+	}
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_START, (uint32_t)rwlock, 0, 0, 0, 0);
+#endif
+loop:
+	lcntval = *lcntaddr;
+	ucntval = *ucntaddr;
+	rw_seq = *seqaddr;
+	
+
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x51515151, lcntval, ucntval, 0);
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x51515151, rw_seq, 0, 0);
+#endif
+	/* check for spurious unlocks */
+	if ((lcntval & PTH_RWL_RBIT) != 0) {
+		newval  = lcntval ;
+		newsval = rw_seq;
+
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+	
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+	
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) == TRUE) {
+			/* spurious unlock, return */
+			error = EINVAL;
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x1a1b1c1d, lcntval, ucntval, 0);
+#endif
+			goto succout;
+		} else
+			goto loop;
+	}
+
+	if (is_rwl_ebit_set(lcntval)) {
+		wrlock = 1;
+#if __DARWIN_UNIX03
+		rwlock->rw_owner = (pthread_t)0;
+#endif /* __DARWIN_UNIX03 */
+	}
+	
+	/* update U */
+	
+	ulval = (ucntval + PTHRW_INC);
+
+	if (OSAtomicCompareAndSwap32Barrier(ucntval, ulval, (volatile int32_t *)ucntaddr) != TRUE)
+		goto loop;
+	
+lp11:
+	/* just validate the l and S values */
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+
+	newval64 = oldval64;
+
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)  {
+		lcntval = *lcntaddr;
+		rw_seq = *seqaddr;
+		goto lp11;
+	}
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0xd1d2d3d4, lcntval, rw_seq, 0);
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0xd1d2d3d4, ulval, 0, 0);
+#endif
+
+	/* last unlock, note U is already updated ? */
+	if((lcntval & PTHRW_COUNT_MASK) == (ulval & PTHRW_COUNT_MASK)) {
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0xbbbbbbbb, lcntval, ucntval, 0);
+#endif
+		/* Set L with R and init bits and set S to L */
+		newval  = (lcntval & PTHRW_COUNT_MASK)| PTHRW_RWLOCK_INIT;
+		newsval = (lcntval & PTHRW_COUNT_MASK)| PTHRW_RWS_INIT;
+
+		oldval64 = (((uint64_t)rw_seq) << 32);
+		oldval64 |= lcntval;
+
+		newval64 = (((uint64_t)newsval) << 32);
+		newval64 |= newval;
+
+		if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)  {
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0xcccccccc, 0, 0, 0);
+#endif
+			lcntval = *lcntaddr;
+			rw_seq = *seqaddr;
+			goto lp11;
+		}
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0xdddddddd, lcntval, ucntval, 0);
+#endif
+		goto succout;
+	}
+
+	/* if it is not exclusive or no Writer/yield pending, skip */
+	if ((lcntval & (PTH_RWL_EBIT | PTH_RWL_WBIT | PTH_RWL_YBIT | PTH_RWL_KBIT)) == 0) {
+		goto succout;
+	}
+
+	/* kernel transition needed? */
+	/* U+1 == S? */
+	if ((ulval + PTHRW_INC) != (rw_seq & PTHRW_COUNT_MASK)) {
+		if ((lcntval & PTH_RWL_UBIT) != 0) {
+			/* if U bit is set U + 2 == S ? */
+			if ((ulval + PTHRW_INC + PTHRW_INC) != (rw_seq & PTHRW_COUNT_MASK))
+				goto succout;
+		} else 
+			goto succout;
+	}
+
+	haswbit = lcntval & PTH_RWL_WBIT;
+	hasubit = lcntval & PTH_RWL_UBIT;
+	hasybit = lcntval & PTH_RWL_YBIT;
+
+	/* reset all bits and set k */
+	newval = (lcntval & PTHRW_COUNT_MASK) | PTH_RWL_KBIT;
+	/* set I bit on S word */	
+	newsval = rw_seq | PTH_RWS_IBIT;
+	if (haswbit != 0)
+		newsval |= PTH_RWS_WSVBIT;
+	if (hasubit != 0)
+		newsval |= PTH_RWS_USVBIT;
+	if (hasybit != 0)
+		newsval |= PTH_RWS_YSVBIT;
+
+	oldval64 = (((uint64_t)rw_seq) << 32);
+	oldval64 |= lcntval;
+	
+	newval64 = (((uint64_t)newsval) << 32);
+	newval64 |= newval;
+	
+	if (OSAtomicCompareAndSwap64Barrier(oldval64, newval64, (volatile int64_t *)lcntaddr) != TRUE)
+		goto lp11;
+
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555511, 1, ulval, 0);
+#endif
+	updateval = __psynch_rw_unlock(orwlock, lcntval, ulval, newsval, rwlock->rw_flags);
+	if (updateval == (uint32_t)-1) {
+		error = errno;
+	} else
+		error = 0;
+	
+	if(error != 0) {
+
+		/* not sure what is the scenario */
+		if(error != EINTR) {
+#if _KSYN_TRACE_
+		set_enable(4);
+#endif /* _KSYN_TRACE_ */
+			(void)pthread_threadid_np(pthread_self(), &myid);
+			LIBC_ABORT("rwunlock from kernel with unknown error %x: tid %x\n", error, (uint32_t)myid);
+			goto succout;
+		}
+		error = 0;
+	}
+	
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_NONE, (uint32_t)rwlock, 0x55555522, 3, lcntval, 0);
+#endif
+
+succout:
+	PLOCKSTAT_RW_RELEASE(orwlock, wrlock);
+#if _KSYN_TRACE_
+	if (__pthread_lock_debug != 0)
+	(void)__kdebug_trace(_KSYN_TRACE_RW_UNLOCK | DBG_FUNC_END, (uint32_t)rwlock, 0xAAAAAAAA, error, 0, 0);
+#endif
+	return(0);
+}
+