MD mutex implementation on amd64.

5 files changed, 153 insertions, 4 deletions

diff --git a/sys/arch/amd64/amd64/genassym.cf b/sys/arch/amd64/amd64/genassym.cf
index 8fc08e90ef2..8b80c559e9e 100644
--- a/sys/arch/amd64/amd64/genassym.cf
+++ b/sys/arch/amd64/amd64/genassym.cf
@@ -1,5 +1,4 @@
-#	$OpenBSD: genassym.cf,v 1.7 2004/06/28 01:52:24 deraadt Exp $
-
+#	$OpenBSD: genassym.cf,v 1.8 2004/07/20 20:17:16 art Exp $
 #	Written by Artur Grabowski art@openbsd.org, Public Domain
 
 include <sys/param.h>
@@ -17,6 +16,7 @@ include <machine/vmparam.h>
 include <machine/intr.h>
 include <machine/pic.h>
 include <machine/i82093var.h>
+include <machine/mutex.h>
 
 export	SRUN
 export	SONPROC
@@ -131,6 +131,11 @@ struct	ioapic_softc
 member	IOAPIC_SC_REG	sc_reg
 member	IOAPIC_SC_DATA	sc_data
 
+struct	mutex
+member	mtx_wantipl
+member	mtx_oldipl
+member	mtx_owner
+
 # pte fields
 export	PG_V
 export	PG_KR
diff --git a/sys/arch/amd64/amd64/mutex.S b/sys/arch/amd64/amd64/mutex.S
new file mode 100644
index 00000000000..a4018c03333
--- /dev/null
+++ b/sys/arch/amd64/amd64/mutex.S
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2004 Artur Grabowski <art@openbsd.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, this list of conditions and the following disclaimer. 
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED ``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 "assym.h"
+
+#include <machine/param.h>
+#include <machine/asm.h>
+#include <machine/segments.h>
+#include <machine/specialreg.h>
+#include <machine/trap.h>
+#include <machine/frameasm.h>
+
+/*
+ * Yeah, we don't really need to implement mtx_init here, but let's keep
+ * all the functions in the same place.
+ */
+ENTRY(mtx_init)
+	movl	%esi, MTX_WANTIPL(%rdi)
+	movl	$0, MTX_OLDIPL(%rdi)
+	movq	$0, MTX_OWNER(%rdi)
+	ret
+
+ENTRY(mtx_enter)
+1:	movl	MTX_WANTIPL(%rdi), %eax
+	movq	CPUVAR(SELF), %rcx
+	movl	CPU_INFO_ILEVEL(%rcx), %edx	# oipl = cpl;
+	cmpl	%edx, %eax			# if (cpl < mtx->mtx_wantipl)
+	jle	2f
+	movl	%eax, CPU_INFO_ILEVEL(%rcx)	#	cpl = mtx->mtx_wantipl;
+2:	/*
+	 * %edx - the old ipl
+	 * %rcx - curcpu()
+	 */
+	xorq	%rax, %rax
+#ifdef MULTIPROCESSOR
+	lock
+#endif
+	cmpxchgq	%rcx, MTX_OWNER(%rdi)	# test_and_set(mtx->mtx_owner)
+	cmpq	$0, %rax
+	jne	3f
+	movl	%edx, MTX_OLDIPL(%rdi)
+	ret
+
+	/* We failed to obtain the lock. splx, spin and retry. */
+3:	pushq	%rdi
+	movl	%edx, %edi
+	call	_C_LABEL(spllower)
+	popq	%rdi
+#ifdef DIAGNOSTIC
+	movq	CPUVAR(SELF), %rcx
+	cmpq	MTX_OWNER(%rdi), %rcx
+	je	5f
+#endif
+4:
+	movq	MTX_OWNER(%rdi), %rax
+	testq	%rax, %rax
+	jz	1b
+	jmp	4b
+#ifdef DIAGNOSTIC
+5:	movq	$6f, %rdi
+	call	_C_LABEL(panic)
+6:	.asciz	"mtx_enter: locking against myself"
+#endif
+	
+ENTRY(mtx_leave)
+	movq	%rdi, %rax
+	xorq	%rcx, %rcx
+	movl	MTX_OLDIPL(%rax), %edi
+	movl	%ecx, MTX_OLDIPL(%rax)
+	movq	%rcx, MTX_OWNER(%rax)
+	call	_C_LABEL(spllower)
+	ret
diff --git a/sys/arch/amd64/conf/files.amd64 b/sys/arch/amd64/conf/files.amd64
index b52a9083423..9d3a3766705 100644
--- a/sys/arch/amd64/conf/files.amd64
+++ b/sys/arch/amd64/conf/files.amd64
@@ -1,4 +1,4 @@
-#	$OpenBSD: files.amd64,v 1.3 2004/06/25 11:03:28 art Exp $
+#	$OpenBSD: files.amd64,v 1.4 2004/07/20 20:17:16 art Exp $
 
 maxpartitions 16
 maxusers 2 16 128
@@ -21,6 +21,7 @@ file	arch/amd64/amd64/Locore.c
 file	arch/amd64/amd64/softintr.c
 file	arch/amd64/amd64/i8259.c
 file	arch/amd64/amd64/cacheinfo.c
+file	arch/amd64/amd64/mutex.S
 
 file	arch/amd64/amd64/intr.c
 file	arch/amd64/amd64/bus_space.c
diff --git a/sys/arch/amd64/include/mutex.h b/sys/arch/amd64/include/mutex.h
new file mode 100644
index 00000000000..ccb1b95774d
--- /dev/null
+++ b/sys/arch/amd64/include/mutex.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2004 Artur Grabowski <art@openbsd.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, this list of conditions and the following disclaimer. 
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED ``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 _AMD64_MUTEX_H_
+#define _AMD64_MUTEX_H_
+
+struct mutex {
+	int mtx_wantipl;
+	int mtx_oldipl;
+	__volatile void *mtx_owner;
+};
+
+#define MUTEX_INITIALIZER(ipl) { (ipl), 0, NULL }
+
+#define MUTEX_ASSERT_LOCKED(mtx) do {					\
+	if ((mtx)->mtx_owner != curcpu())				\
+		panic("mutex %p not held in %s\n", (mtx), __func__);	\
+} while (0)
+
+#define MUTEX_ASSERT_UNLOCKED(mtx) do {					\
+	if ((mtx)->mtx_owner == curcpu())				\
+		panic("mutex %p held in %s\n", (mtx), __func__);	\
+} while (0)
+
+#define MUTEX_OLDIPL(mtx)	(mtx)->mtx_oldipl
+
+#endif
diff --git a/sys/arch/amd64/include/types.h b/sys/arch/amd64/include/types.h
index 8ef62891ef4..3beda9b0da4 100644
--- a/sys/arch/amd64/include/types.h
+++ b/sys/arch/amd64/include/types.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: types.h,v 1.4 2004/06/28 01:52:26 deraadt Exp $	*/
+/*	$OpenBSD: types.h,v 1.5 2004/07/20 20:17:16 art Exp $	*/
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -71,5 +71,6 @@ typedef long			register_t;
 #define __HAVE_GENERIC_SOFT_INTERRUPTS
 #define __HAVE_CPUINFO
 #define	__HAVE_EVCOUNT
+#define __HAVE_MUTEX
 
 #endif	/* _MACHTYPES_H_ */