Move rtems/freebsd to freebsd and contrib to freebsd/contrib

1 files changed, 307 insertions, 0 deletions

diff --git a/freebsd/sys/sx.h b/freebsd/sys/sx.h
new file mode 100644
index 00000000..1243d30e
--- /dev/null
+++ b/freebsd/sys/sx.h
@@ -0,0 +1,307 @@
+/*-
+ * Copyright (c) 2007 Attilio Rao <attilio@freebsd.org>
+ * Copyright (c) 2001 Jason Evans <jasone@freebsd.org>
+ * 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(s), this list of conditions and the following disclaimer as
+ *    the first lines of this file unmodified other than the possible 
+ *    addition of one or more copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef	_SYS_SX_HH_
+#define	_SYS_SX_HH_
+
+#include <rtems/freebsd/sys/_lock.h>
+#include <rtems/freebsd/sys/_sx.h>
+
+#ifdef	_KERNEL
+#include <rtems/freebsd/sys/pcpu.h>
+#include <rtems/freebsd/sys/lock_profile.h>
+#include <rtems/freebsd/sys/lockstat.h>
+#include <rtems/freebsd/machine/atomic.h>
+#endif
+
+#ifdef __rtems__
+#define SX_NOINLINE 1
+#define _sx_slock _bsd__sx_xlock
+#define _sx_try_slock _bsd__sx_try_xlock
+#define _sx_sunlock _bsd__sx_xunlock
+#endif /* __rtems__ */
+
+/*
+ * In general, the sx locks and rwlocks use very similar algorithms.
+ * The main difference in the implementations is how threads are
+ * blocked when a lock is unavailable.  For this, sx locks use sleep
+ * queues which do not support priority propagation, and rwlocks use
+ * turnstiles which do.
+ *
+ * The sx_lock field consists of several fields.  The low bit
+ * indicates if the lock is locked with a shared or exclusive lock.  A
+ * value of 0 indicates an exclusive lock, and a value of 1 indicates
+ * a shared lock.  Bit 1 is a boolean indicating if there are any
+ * threads waiting for a shared lock.  Bit 2 is a boolean indicating
+ * if there are any threads waiting for an exclusive lock.  Bit 3 is a
+ * boolean indicating if an exclusive lock is recursively held.  The
+ * rest of the variable's definition is dependent on the value of the
+ * first bit.  For an exclusive lock, it is a pointer to the thread
+ * holding the lock, similar to the mtx_lock field of mutexes.  For
+ * shared locks, it is a count of read locks that are held.
+ *
+ * When the lock is not locked by any thread, it is encoded as a
+ * shared lock with zero waiters.
+ */
+
+#define	SX_LOCK_SHARED			0x01
+#define	SX_LOCK_SHARED_WAITERS		0x02
+#define	SX_LOCK_EXCLUSIVE_WAITERS	0x04
+#define	SX_LOCK_RECURSED		0x08
+#define	SX_LOCK_FLAGMASK						\
+	(SX_LOCK_SHARED | SX_LOCK_SHARED_WAITERS |			\
+	SX_LOCK_EXCLUSIVE_WAITERS | SX_LOCK_RECURSED)
+
+#define	SX_OWNER(x)			((x) & ~SX_LOCK_FLAGMASK)
+#define	SX_SHARERS_SHIFT		4
+#define	SX_SHARERS(x)			(SX_OWNER(x) >> SX_SHARERS_SHIFT)
+#define	SX_SHARERS_LOCK(x)						\
+	((x) << SX_SHARERS_SHIFT | SX_LOCK_SHARED)
+#define	SX_ONE_SHARER			(1 << SX_SHARERS_SHIFT)
+
+#define	SX_LOCK_UNLOCKED		SX_SHARERS_LOCK(0)
+#define	SX_LOCK_DESTROYED						\
+	(SX_LOCK_SHARED_WAITERS | SX_LOCK_EXCLUSIVE_WAITERS)
+
+#ifdef _KERNEL
+
+/*
+ * Function prototipes.  Routines that start with an underscore are not part
+ * of the public interface and are wrappered with a macro.
+ */
+void	sx_sysinit(void *arg);
+#define	sx_init(sx, desc)	sx_init_flags((sx), (desc), 0)
+void	sx_init_flags(struct sx *sx, const char *description, int opts);
+void	sx_destroy(struct sx *sx);
+int	_sx_slock(struct sx *sx, int opts, const char *file, int line);
+int	_sx_xlock(struct sx *sx, int opts, const char *file, int line);
+int	_sx_try_slock(struct sx *sx, const char *file, int line);
+int	_sx_try_xlock(struct sx *sx, const char *file, int line);
+void	_sx_sunlock(struct sx *sx, const char *file, int line);
+void	_sx_xunlock(struct sx *sx, const char *file, int line);
+int	_sx_try_upgrade(struct sx *sx, const char *file, int line);
+void	_sx_downgrade(struct sx *sx, const char *file, int line);
+int	_sx_xlock_hard(struct sx *sx, uintptr_t tid, int opts,
+	    const char *file, int line);
+int	_sx_slock_hard(struct sx *sx, int opts, const char *file, int line);
+void	_sx_xunlock_hard(struct sx *sx, uintptr_t tid, const char *file, int
+	    line);
+void	_sx_sunlock_hard(struct sx *sx, const char *file, int line);
+#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
+void	_sx_assert(struct sx *sx, int what, const char *file, int line);
+#endif
+#ifdef DDB
+int	sx_chain(struct thread *td, struct thread **ownerp);
+#endif
+
+struct sx_args {
+	struct sx 	*sa_sx;
+	const char	*sa_desc;
+};
+
+#define	SX_SYSINIT(name, sxa, desc)					\
+	static struct sx_args name##_args = {				\
+		(sxa),							\
+		(desc)							\
+	};								\
+	SYSINIT(name##_sx_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
+	    sx_sysinit, &name##_args);					\
+	SYSUNINIT(name##_sx_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE,	\
+	    sx_destroy, (sxa))
+
+#ifndef __rtems__
+/*
+ * Full lock operations that are suitable to be inlined in non-debug kernels.
+ * If the lock can't be acquired or released trivially then the work is
+ * deferred to 'tougher' functions.
+ */
+
+/* Acquire an exclusive lock. */
+static __inline int
+__sx_xlock(struct sx *sx, struct thread *td, int opts, const char *file,
+    int line)
+{
+	uintptr_t tid = (uintptr_t)td;
+	int error = 0;
+
+	if (!atomic_cmpset_acq_ptr(&sx->sx_lock, SX_LOCK_UNLOCKED, tid))
+		error = _sx_xlock_hard(sx, tid, opts, file, line);
+	else 
+		LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(LS_SX_XLOCK_ACQUIRE,
+		    sx, 0, 0, file, line);
+
+	return (error);
+}
+
+/* Release an exclusive lock. */
+static __inline void
+__sx_xunlock(struct sx *sx, struct thread *td, const char *file, int line)
+{
+	uintptr_t tid = (uintptr_t)td;
+
+	if (!atomic_cmpset_rel_ptr(&sx->sx_lock, tid, SX_LOCK_UNLOCKED))
+		_sx_xunlock_hard(sx, tid, file, line);
+}
+
+/* Acquire a shared lock. */
+static __inline int
+__sx_slock(struct sx *sx, int opts, const char *file, int line)
+{
+	uintptr_t x = sx->sx_lock;
+	int error = 0;
+
+	if (!(x & SX_LOCK_SHARED) ||
+	    !atomic_cmpset_acq_ptr(&sx->sx_lock, x, x + SX_ONE_SHARER))
+		error = _sx_slock_hard(sx, opts, file, line);
+	else
+		LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(LS_SX_SLOCK_ACQUIRE, sx, 0,
+		    0, file, line);
+
+	return (error);
+}
+
+/*
+ * Release a shared lock.  We can just drop a single shared lock so
+ * long as we aren't trying to drop the last shared lock when other
+ * threads are waiting for an exclusive lock.  This takes advantage of
+ * the fact that an unlocked lock is encoded as a shared lock with a
+ * count of 0.
+ */
+static __inline void
+__sx_sunlock(struct sx *sx, const char *file, int line)
+{
+	uintptr_t x = sx->sx_lock;
+
+	if (x == (SX_SHARERS_LOCK(1) | SX_LOCK_EXCLUSIVE_WAITERS) ||
+	    !atomic_cmpset_rel_ptr(&sx->sx_lock, x, x - SX_ONE_SHARER))
+		_sx_sunlock_hard(sx, file, line);
+}
+#endif /* __rtems__ */
+
+/*
+ * Public interface for lock operations.
+ */
+#ifndef LOCK_DEBUG
+#error	"LOCK_DEBUG not defined, include <sys/lock.h> before <sys/sx.h>"
+#endif
+#if	(LOCK_DEBUG > 0) || defined(SX_NOINLINE)
+#define	sx_xlock(sx)		(void)_sx_xlock((sx), 0, LOCK_FILE, LOCK_LINE)
+#define	sx_xlock_sig(sx)						\
+	_sx_xlock((sx), SX_INTERRUPTIBLE, LOCK_FILE, LOCK_LINE)
+#define	sx_xunlock(sx)		_sx_xunlock((sx), LOCK_FILE, LOCK_LINE)
+#define	sx_slock(sx)		(void)_sx_slock((sx), 0, LOCK_FILE, LOCK_LINE)
+#define	sx_slock_sig(sx)						\
+	_sx_slock((sx), SX_INTERRUPTIBLE, LOCK_FILE, LOCK_LINE)
+#define	sx_sunlock(sx)		_sx_sunlock((sx), LOCK_FILE, LOCK_LINE)
+#else
+#define	sx_xlock(sx)							\
+	(void)__sx_xlock((sx), curthread, 0, LOCK_FILE, LOCK_LINE)
+#define	sx_xlock_sig(sx)						\
+	__sx_xlock((sx), curthread, SX_INTERRUPTIBLE, LOCK_FILE, LOCK_LINE)
+#define	sx_xunlock(sx)							\
+	__sx_xunlock((sx), curthread, LOCK_FILE, LOCK_LINE)
+#define	sx_slock(sx)		(void)__sx_slock((sx), 0, LOCK_FILE, LOCK_LINE)
+#define	sx_slock_sig(sx)						\
+	__sx_slock((sx), SX_INTERRUPTIBLE, LOCK_FILE, LOCK_LINE)
+#define	sx_sunlock(sx)		__sx_sunlock((sx), LOCK_FILE, LOCK_LINE)
+#endif	/* LOCK_DEBUG > 0 || SX_NOINLINE */
+#define	sx_try_slock(sx)	_sx_try_slock((sx), LOCK_FILE, LOCK_LINE)
+#define	sx_try_xlock(sx)	_sx_try_xlock((sx), LOCK_FILE, LOCK_LINE)
+#define	sx_try_upgrade(sx)	_sx_try_upgrade((sx), LOCK_FILE, LOCK_LINE)
+#define	sx_downgrade(sx)	_sx_downgrade((sx), LOCK_FILE, LOCK_LINE)
+
+/*
+ * Return a pointer to the owning thread if the lock is exclusively
+ * locked.
+ */
+#ifndef __rtems__
+#define	sx_xholder(sx)							\
+	((sx)->sx_lock & SX_LOCK_SHARED ? NULL :			\
+	(struct thread *)SX_OWNER((sx)->sx_lock))
+
+#define	sx_xlocked(sx)							\
+	(((sx)->sx_lock & ~(SX_LOCK_FLAGMASK & ~SX_LOCK_SHARED)) ==	\
+	    (uintptr_t)curthread)
+#else /* __rtems__ */
+int sx_xlocked(struct sx *sx);
+#endif /* __rtems__ */
+
+#define	sx_unlock(sx) do {						\
+	if (sx_xlocked(sx))						\
+		sx_xunlock(sx);						\
+	else								\
+		sx_sunlock(sx);						\
+} while (0)
+
+#define	sx_sleep(chan, sx, pri, wmesg, timo)				\
+	_sleep((chan), &(sx)->lock_object, (pri), (wmesg), (timo))
+
+/*
+ * Options passed to sx_init_flags().
+ */
+#define	SX_DUPOK		0x01
+#define	SX_NOPROFILE		0x02
+#define	SX_NOWITNESS		0x04
+#define	SX_QUIET		0x08
+#define	SX_NOADAPTIVE		0x10
+#define	SX_RECURSE		0x20
+
+/*
+ * Options passed to sx_*lock_hard().
+ */
+#define	SX_INTERRUPTIBLE	0x40
+
+#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
+#define	SA_LOCKED		LA_LOCKED
+#define	SA_SLOCKED		LA_SLOCKED
+#define	SA_XLOCKED		LA_XLOCKED
+#define	SA_UNLOCKED		LA_UNLOCKED
+#define	SA_RECURSED		LA_RECURSED
+#define	SA_NOTRECURSED		LA_NOTRECURSED
+
+/* Backwards compatability. */
+#define	SX_LOCKED		LA_LOCKED
+#define	SX_SLOCKED		LA_SLOCKED
+#define	SX_XLOCKED		LA_XLOCKED
+#define	SX_UNLOCKED		LA_UNLOCKED
+#define	SX_RECURSED		LA_RECURSED
+#define	SX_NOTRECURSED		LA_NOTRECURSED
+#endif
+
+#ifdef INVARIANTS
+#define	sx_assert(sx, what)	_sx_assert((sx), (what), LOCK_FILE, LOCK_LINE)
+#else
+#define	sx_assert(sx, what)	(void)0
+#endif
+
+#endif /* _KERNEL */
+
+#endif /* !_SYS_SX_HH_ */