Break out stack(9) from ddb(4):

- Introduce per-architecture stack_machdep.c to hold stack_save(9).
- Introduce per-architecture machine/stack.h to capture any common
  definitions required between db_trace.c and stack_machdep.c.
- Add new kernel option "options STACK"; we will build in stack(9) if it is
  defined, or also if "options DDB" is defined to provide compatibility
  with existing users of stack(9).

Add new stack_save_td(9) function, which allows the capture of a stacktrace
of another thread rather than the current thread, which the existing
stack_save(9) was limited to.  It requires that the thread be neither
swapped out nor running, which is the responsibility of the consumer to
enforce.

Update stack(9) man page.

Build tested:	amd64, arm, i386, ia64, powerpc, sparc64, sun4v
Runtime tested:	amd64 (rwatson), arm (cognet), i386 (rwatson)

4 files changed, 133 insertions, 38 deletions

diff --git a/sys/amd64/amd64/db_trace.c b/sys/amd64/amd64/db_trace.c
index 548c36c..c4e552d 100644
--- a/sys/amd64/amd64/db_trace.c
+++ b/sys/amd64/amd64/db_trace.c
@@ -38,6 +38,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/md_var.h>
 #include <machine/pcb.h>
 #include <machine/reg.h>
+#include <machine/stack.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
@@ -177,18 +178,6 @@ db_ss(struct db_variable *vp, db_expr_t *valuep, int op)
 	return (1);
 }
 
-/*
- * Stack trace.
- */
-#define	INKERNEL(va) (((va) >= DMAP_MIN_ADDRESS && (va) < DMAP_MAX_ADDRESS) \
-	    || ((va) >= KERNBASE && (va) < VM_MAX_KERNEL_ADDRESS))
-
-struct amd64_frame {
-	struct amd64_frame	*f_frame;
-	long			f_retaddr;
-	long			f_arg0;
-};
-
 #define NORMAL		0
 #define	TRAP		1
 #define	INTERRUPT	2
@@ -505,32 +494,6 @@ db_trace_thread(struct thread *thr, int count)
 		    ctx->pcb_rip, count));
 }
 
-void
-stack_save(struct stack *st)
-{
-	struct amd64_frame *frame;
-	vm_offset_t callpc;
-	register_t rbp;
-
-	stack_zero(st);
-	__asm __volatile("movq %%rbp,%0" : "=r" (rbp));
-	frame = (struct amd64_frame *)rbp;
-	while (1) {
-		if (!INKERNEL((long)frame))
-			break;
-		callpc = frame->f_retaddr;
-		if (!INKERNEL(callpc))
-			break;
-		if (stack_put(st, callpc) == -1)
-			break;
-		if (frame->f_frame <= frame ||
-		    (vm_offset_t)frame->f_frame >=
-		    (vm_offset_t)rbp + KSTACK_PAGES * PAGE_SIZE)
-			break;
-		frame = frame->f_frame;
-	}
-}
-
 int
 amd64_set_watch(watchnum, watchaddr, size, access, d)
 	int watchnum;
diff --git a/sys/amd64/amd64/stack_machdep.c b/sys/amd64/amd64/stack_machdep.c
new file mode 100644
index 0000000..57908e2
--- /dev/null
+++ b/sys/amd64/amd64/stack_machdep.c
@@ -0,0 +1,87 @@
+/*-
+ * Copyright (c) 2005 Antoine Brodin
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/stack.h>
+
+#include <machine/pcb.h>
+#include <machine/stack.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/pmap.h>
+
+static void
+stack_capture(struct stack *st, register_t rbp)
+{
+	struct amd64_frame *frame;
+	vm_offset_t callpc;
+
+	stack_zero(st);
+	frame = (struct amd64_frame *)rbp;
+	while (1) {
+		if (!INKERNEL((long)frame))
+			break;
+		callpc = frame->f_retaddr;
+		if (!INKERNEL(callpc))
+			break;
+		if (stack_put(st, callpc) == -1)
+			break;
+		if (frame->f_frame <= frame ||
+		    (vm_offset_t)frame->f_frame >=
+		    (vm_offset_t)rbp + KSTACK_PAGES * PAGE_SIZE)
+			break;
+		frame = frame->f_frame;
+	}
+}
+
+void
+stack_save_td(struct stack *st, struct thread *td)
+{
+	register_t rbp;
+
+	if (TD_IS_SWAPPED(td))
+		panic("stack_save_td: swapped");
+	if (TD_IS_RUNNING(td))
+		panic("stack_save_td: running");
+
+	rbp = td->td_pcb->pcb_rbp;
+	stack_capture(st, rbp);
+}
+
+void
+stack_save(struct stack *st)
+{
+	register_t rbp;
+
+	__asm __volatile("movq %%rbp,%0" : "=r" (rbp));
+	stack_capture(st, rbp);
+}
diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC
index a809f8e..3786bba 100644
--- a/sys/amd64/conf/GENERIC
+++ b/sys/amd64/conf/GENERIC
@@ -54,6 +54,7 @@ options 	COMPAT_FREEBSD5		# Compatible with FreeBSD5
 options 	COMPAT_FREEBSD6		# Compatible with FreeBSD6
 options 	SCSI_DELAY=5000		# Delay (in ms) before probing SCSI
 options 	KTRACE			# ktrace(1) support
+options 	STACK			# stack(9) support
 options 	SYSVSHM			# SYSV-style shared memory
 options 	SYSVMSG			# SYSV-style message queues
 options 	SYSVSEM			# SYSV-style semaphores
diff --git a/sys/amd64/include/stack.h b/sys/amd64/include/stack.h
new file mode 100644
index 0000000..2a70d30
--- /dev/null
+++ b/sys/amd64/include/stack.h
@@ -0,0 +1,44 @@
+/*-
+ * Mach Operating System
+ * Copyright (c) 1991,1990 Carnegie Mellon University
+ * All Rights Reserved.
+ *
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * Carnegie Mellon requests users of this software to return to
+ *
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ *
+ * any improvements or extensions that they make and grant Carnegie the
+ * rights to redistribute these changes.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _MACHINE_STACK_H_
+#define	_MACHINE_STACK_H_
+
+/*
+ * Stack trace.
+ */
+#define	INKERNEL(va) (((va) >= DMAP_MIN_ADDRESS && (va) < DMAP_MAX_ADDRESS) \
+	    || ((va) >= KERNBASE && (va) < VM_MAX_KERNEL_ADDRESS))
+
+struct amd64_frame {
+	struct amd64_frame	*f_frame;
+	long			f_retaddr;
+	long			f_arg0;
+};
+
+#endif /* !_MACHINE_STACK_H_ */