Rework the __mp_lock code to not spin at spllock(), kinda similar to the

x86 __mp_lock changes, but keeping the internal __cpu_simplelock_t to
guarantee atomic access to the __mp_lock fields.

6 files changed, 254 insertions, 192 deletions

diff --git a/sys/arch/aviion/include/mplock.h b/sys/arch/aviion/include/mplock.h
new file mode 100644
index 00000000000..4193327f6e6
--- /dev/null
+++ b/sys/arch/aviion/include/mplock.h
@@ -0,0 +1,3 @@
+/*	$OpenBSD: mplock.h,v 1.1 2007/12/02 21:20:15 miod Exp $	*/
+/* public domain */
+#include <m88k/mplock.h>
diff --git a/sys/arch/luna88k/include/mplock.h b/sys/arch/luna88k/include/mplock.h
new file mode 100644
index 00000000000..d1ff5e50d69
--- /dev/null
+++ b/sys/arch/luna88k/include/mplock.h
@@ -0,0 +1,3 @@
+/*	$OpenBSD: mplock.h,v 1.1 2007/12/02 21:20:17 miod Exp $	*/
+/* public domain */
+#include <m88k/mplock.h>
diff --git a/sys/arch/m88k/conf/files.m88k b/sys/arch/m88k/conf/files.m88k
index 65e2692ebb7..53b9f7d7dc5 100644
--- a/sys/arch/m88k/conf/files.m88k
+++ b/sys/arch/m88k/conf/files.m88k
@@ -1,4 +1,4 @@
-#	$OpenBSD: files.m88k,v 1.17 2007/11/25 18:25:28 deraadt Exp $
+#	$OpenBSD: files.m88k,v 1.18 2007/12/02 21:20:17 miod Exp $
 
 file	arch/m88k/m88k/db_disasm.c			ddb
 file	arch/m88k/m88k/db_interface.c			ddb
@@ -11,6 +11,7 @@ file	arch/m88k/m88k/m88110_fp.S			m88110
 file	arch/m88k/m88k/m88110_mmu.S			m88110
 file	arch/m88k/m88k/m8820x_machdep.c			m88100
 file	arch/m88k/m88k/m88k_machdep.c
+file	arch/m88k/m88k/mplock.c				multiprocessor
 file	arch/m88k/m88k/mutex.S
 file	arch/m88k/m88k/pmap.c
 file	arch/m88k/m88k/process.S
diff --git a/sys/arch/m88k/include/mplock.h b/sys/arch/m88k/include/mplock.h
new file mode 100644
index 00000000000..94ffede4ac1
--- /dev/null
+++ b/sys/arch/m88k/include/mplock.h
@@ -0,0 +1,71 @@
+/*	$OpenBSD: mplock.h,v 1.1 2007/12/02 21:20:17 miod Exp $	*/
+
+/*
+ * Copyright (c) 2004 Niklas Hallqvist.  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 ``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 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.
+ */
+
+#ifndef _MACHINE_MPLOCK_H_
+#define _MACHINE_MPLOCK_H_
+
+#ifndef _LOCORE
+
+/*
+ * Really simple spinlock implementation with recursive capabilities.
+ * Correctness is paramount, no fancyness allowed.
+ */
+
+struct __mp_lock {
+	__cpu_simple_lock_t mpl_lock;
+	volatile struct cpu_info *mpl_cpu;
+	volatile int mpl_count;
+};
+
+static __inline void
+__mp_lock_init(struct __mp_lock *mpl)
+{
+	__cpu_simple_lock_init(&mpl->mpl_lock);
+	mpl->mpl_cpu = NULL;
+	mpl->mpl_count = 0;
+}
+
+void	__mp_lock(struct __mp_lock *);
+void	__mp_unlock(struct __mp_lock *);
+int	__mp_release_all(struct __mp_lock *);
+int	__mp_release_all_but_one(struct __mp_lock *);
+
+static __inline__ void
+__mp_acquire_count(struct __mp_lock *mpl, int count)
+{
+	while (count--)
+		__mp_lock(mpl);
+}
+
+static __inline__ int
+__mp_lock_held(struct __mp_lock *mpl)
+{
+	return mpl->mpl_cpu == curcpu();
+}
+
+#endif
+
+#endif /* !_MACHINE_MPLOCK_H */
diff --git a/sys/arch/m88k/m88k/mplock.c b/sys/arch/m88k/m88k/mplock.c
new file mode 100644
index 00000000000..8e8903be465
--- /dev/null
+++ b/sys/arch/m88k/m88k/mplock.c
@@ -0,0 +1,172 @@
+/*	$OpenBSD: mplock.c,v 1.1 2007/12/02 21:20:17 miod Exp $	*/
+
+/*
+ * Copyright (c) 2004 Niklas Hallqvist.  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 ``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 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.
+ */
+
+#include <sys/param.h>
+#include <sys/lock.h>
+#include <sys/systm.h>
+
+#include <machine/asm_macro.h>
+#include <machine/lock.h>
+
+#include <ddb/db_output.h>
+
+#if defined(MP_LOCKDEBUG)
+#ifndef DDB
+#error "MP_LOCKDEBUG requires DDB"
+#endif
+
+/* CPU-dependent timing, needs this to be settable from ddb. */
+extern int __mp_lock_spinout;
+#endif
+
+#define	SPINLOCK_SPIN_HOOK	do { /* nothing */ } while (0)
+
+static __inline void
+__mp_lock_spin(struct __mp_lock *mpl)
+{
+#ifndef MP_LOCKDEBUG
+	while (mpl->mpl_count != 0)
+		SPINLOCK_SPIN_HOOK;
+#else
+	int ticks = __mp_lock_spinout;
+
+	while (mpl->mpl_count != 0 && ticks-- > 0)
+		SPINLOCK_SPIN_HOOK;
+
+	if (ticks == 0) {
+ 		db_printf("__mp_lock(0x%x): lock spun out", mpl);
+		Debugger();
+	}
+#endif
+}
+
+void
+__mp_lock(struct __mp_lock *mpl)
+{
+	struct cpu_info *ci = curcpu();
+
+	/*
+	 * Please notice that mpl_count gets incremented twice for the
+	 * first lock. This is on purpose. The way we release the lock
+	 * in mp_unlock is to decrement the mpl_count and then check if
+	 * the lock should be released. Since mpl_count is what we're
+	 * spinning on, decrementing it in mpl_unlock to 0 means that
+	 * we can't clear mpl_cpu, because we're no longer holding the
+	 * lock. In theory mpl_cpu doesn't need to be cleared, but it's
+	 * safer to clear it and besides, setting mpl_count to 2 on the
+	 * first lock makes most of this code much simpler.
+	 */
+
+	for (;;) {
+		u_int32_t psr = get_psr();
+
+		set_psr(psr | PSR_IND);
+		__cpu_simple_lock(&mpl->mpl_lock);
+		if (mpl->mpl_count == 0) {
+			mpl->mpl_count = 1;
+			mpl->mpl_cpu = ci;
+		}
+		if (mpl->mpl_cpu == ci) {
+			mpl->mpl_count++;
+			__cpu_simple_unlock(&mpl->mpl_lock);
+			set_psr(psr);
+			break;
+		}
+		__cpu_simple_unlock(&mpl->mpl_lock);
+		set_psr(psr);
+
+		__mp_lock_spin(mpl);
+	}
+}
+
+void
+__mp_unlock(struct __mp_lock *mpl)
+{
+	u_int32_t psr = get_psr();
+
+#ifdef MP_LOCKDEBUG
+	if (mpl->mpl_cpu != curcpu()) {
+		db_printf("__mp_unlock(%p): not held lock\n", mpl);
+		Debugger();
+	}
+#endif
+
+	set_psr(psr | PSR_IND);
+	__cpu_simple_lock(&mpl->mpl_lock);
+	if (--mpl->mpl_count == 1) {
+		mpl->mpl_cpu = NULL;
+		mpl->mpl_count = 0;
+	}
+	__cpu_simple_unlock(&mpl->mpl_lock);
+	set_psr(psr);
+}
+
+int
+__mp_release_all(struct __mp_lock *mpl)
+{
+	u_int32_t psr = get_psr();
+	int rv;
+
+#ifdef MP_LOCKDEBUG
+	if (mpl->mpl_cpu != curcpu()) {
+		db_printf("__mp_release_all(%p): not held lock\n", mpl);
+		Debugger();
+	}
+#endif
+
+	set_psr(psr | PSR_IND);
+	__cpu_simple_lock(&mpl->mpl_lock);
+	rv = mpl->mpl_count - 1;
+	mpl->mpl_cpu = NULL;
+	mpl->mpl_count = 0;
+	__cpu_simple_unlock(&mpl->mpl_lock);
+	set_psr(psr);
+
+	return (rv);
+}
+
+int
+__mp_release_all_but_one(struct __mp_lock *mpl)
+{
+	u_int32_t psr = get_psr();
+	int rv;
+
+#ifdef MP_LOCKDEBUG
+	if (mpl->mpl_cpu != curcpu()) {
+		db_printf("__mp_release_all_but_one(%p): not held lock\n", mpl);
+		Debugger();
+	}
+#endif
+
+	set_psr(psr | PSR_IND);
+	__cpu_simple_lock(&mpl->mpl_lock);
+	rv = mpl->mpl_count - 2;
+	mpl->mpl_count = 2;
+	__cpu_simple_unlock(&mpl->mpl_lock);
+	set_psr(psr);
+
+	return (rv);
+}
diff --git a/sys/arch/mvme88k/include/mplock.h b/sys/arch/mvme88k/include/mplock.h
index 8f87c895aae..a4e5204c65c 100644
--- a/sys/arch/mvme88k/include/mplock.h
+++ b/sys/arch/mvme88k/include/mplock.h
@@ -1,191 +1,3 @@
-/*	$OpenBSD: mplock.h,v 1.1 2007/11/26 17:15:29 art Exp $	*/
-
-/*
- * Copyright (c) 2004 Niklas Hallqvist.  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 ``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 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.
- */
-
-#ifndef _MACHINE_MPLOCK_H_
-#define _MACHINE_MPLOCK_H_
-
-/*
- * Really simple spinlock implementation with recursive capabilities.
- * Correctness is paramount, no fancyness allowed.
- */
-
-struct __mp_lock {
-	__cpu_simple_lock_t mpl_lock;
-	cpuid_t	mpl_cpu;
-	int	mpl_count;
-};
-
-static __inline void
-__mp_lock_init(struct __mp_lock *lock)
-{
-	__cpu_simple_lock_init(&lock->mpl_lock);
-	lock->mpl_cpu = LK_NOCPU;
-	lock->mpl_count = 0;
-}
-
-#if defined(MP_LOCKDEBUG)
-#ifndef DDB
-#error "MP_LOCKDEBUG requires DDB"
-#endif
-
-extern void Debugger(void);
-extern int db_printf(const char *, ...)
-    __attribute__((__format__(__kprintf__,1,2)));
-
-/* CPU-dependent timing, needs this to be settable from ddb. */
-extern int __mp_lock_spinout;
-#endif
-
-static __inline void
-__mp_lock(struct __mp_lock *lock)
-{
-	int s = spllock();
-
-	if (lock->mpl_cpu != cpu_number()) {
-#ifndef MP_LOCKDEBUG
-		__cpu_simple_lock(&lock->mpl_lock);
-#else
-		{
-			int got_it;
-			do {
-				int ticks = __mp_lock_spinout;
-
-				do {
-					got_it = __cpu_simple_lock_try(
-					    &lock->mpl_lock);
-				} while (!got_it && ticks-- > 0);
-				if (!got_it) {
- 					db_printf(
-					    "__mp_lock(0x%x): lock spun out",
-					    lock);
-					Debugger();
-				}
-			} while (!got_it);
-		}
-#endif
-		lock->mpl_cpu = cpu_number();
-	}
-	lock->mpl_count++;
-	splx(s);
-}
-
-/*
- * Try to acquire the lock, if another cpu has it, fill it in the
- * call-by-reference cpu parameter.  Return true if acquired.
- */
-static __inline int
-__mp_lock_try(struct __mp_lock *lock, cpuid_t *cpu)
-{
-	int s = spllock();
-
-	if (lock->mpl_cpu != cpu_number()) {
-		if (!__cpu_simple_lock_try(&lock->mpl_lock)) {
-			*cpu = lock->mpl_cpu;
-			splx(s);
-			return 0;
-		}
-		lock->mpl_cpu = cpu_number();
-	}
-	lock->mpl_count++;
-	splx(s);
-	return 1;
-}
-
-static __inline void
-__mp_unlock(struct __mp_lock *lock)
-{
-	int s = spllock();
-
-#ifdef MP_LOCKDEBUG
-	if (lock->mpl_count == 0 || lock->mpl_cpu == LK_NOCPU) {
-		db_printf("__mp_unlock(0x%x): releasing not locked lock\n",
-		    lock);
-		Debugger();
-	}
-#endif
-
-	if (--lock->mpl_count == 0) {
-		lock->mpl_cpu = LK_NOCPU;
-		__cpu_simple_unlock(&lock->mpl_lock);
-	}
-	splx(s);
-}
-
-static __inline int
-__mp_release_all(struct __mp_lock *lock) {
-	int s = spllock();
-	int rv = lock->mpl_count;
-
-#ifdef MP_LOCKDEBUG
-	if (lock->mpl_count == 0 || lock->mpl_cpu == LK_NOCPU) {
-		db_printf(
-		    "__mp_release_all(0x%x): releasing not locked lock\n",
-		    lock);
-		Debugger();
-	}
-#endif
-
-	lock->mpl_cpu = LK_NOCPU;
-	lock->mpl_count = 0;
-	__cpu_simple_unlock(&lock->mpl_lock);
-	splx(s);
-	return (rv);
-}
-
-static __inline int
-__mp_release_all_but_one(struct __mp_lock *lock) {
-	int s = spllock();
-	int rv = lock->mpl_count - 1;
-
-#ifdef MP_LOCKDEBUG
-	if (lock->mpl_count == 0 || lock->mpl_cpu == LK_NOCPU) {
-		db_printf(
-		    "__mp_release_all_but_one(0x%x): releasing not locked lock\n",
-		    lock);
-		Debugger();
-	}
-#endif
-
-	lock->mpl_count = 1;
-	splx(s);
-	return (rv);
-}
-
-static __inline void
-__mp_acquire_count(struct __mp_lock *lock, int count) {
-	int s = spllock();
-
-	while (count--)
-		__mp_lock(lock);
-	splx(s);
-}
-
-static __inline int
-__mp_lock_held(struct __mp_lock *lock) {
-	return lock->mpl_count && lock->mpl_cpu == cpu_number();
-}
-
-#endif /* !_MACHINE_MPLOCK_H */
+/*	$OpenBSD: mplock.h,v 1.2 2007/12/02 21:20:17 miod Exp $	*/
+/* public domain */
+#include <m88k/mplock.h>