Make vpanic() externally visible so that it can be called as part of the

DTrace panic() action.

Differential Revision:	https://reviews.freebsd.org/D2349
Reviewed by:	avg
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division

share/man/man9/Makefile

@@ -1135,6 +1135,7 @@ MLINKS+=osd.9 osd_call.9 \
 	osd.9 osd_get.9 \
 	osd.9 osd_register.9 \
 	osd.9 osd_set.9
+MLINKS+=panic.9 vpanic.9
 MLINKS+=pbuf.9 getpbuf.9 \
 	pbuf.9 relpbuf.9 \
 	pbuf.9 trypbuf.9

share/man/man9/panic.9

@@ -31,7 +31,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 11, 1995
+.Dd April 23, 2015
 .Dt PANIC 9
 .Os
 .Sh NAME
@@ -42,10 +42,14 @@
 .In sys/systm.h
 .Ft void
 .Fn panic "const char *fmt" ...
+.Ft void
+.Fn vpanic "const char *fmt" "va_list ap"
 .Sh DESCRIPTION
 The
 .Fn panic
-function terminates the running system.
+and
+.Fn vpanic
+functions terminate the running system.
 The message
 .Fa fmt
 is a

sys/kern/kern_shutdown.c

@@ -154,7 +154,6 @@ static void poweroff_wait(void *, int);
 static void shutdown_halt(void *junk, int howto);
 static void shutdown_panic(void *junk, int howto);
 static void shutdown_reset(void *junk, int howto);
-static void vpanic(const char *fmt, va_list ap) __dead2;
 
 /* register various local shutdown events */
 static void
@@ -676,7 +675,7 @@ panic(const char *fmt, ...)
 	vpanic(fmt, ap);
 }
 
-static void
+void
 vpanic(const char *fmt, va_list ap)
 {
 #ifdef SMP

sys/sys/systm.h

@@ -187,6 +187,7 @@ void	*phashinit(int count, struct malloc_type *type, u_long *nentries);
 void	g_waitidle(void);
 
 void	panic(const char *, ...) __dead2 __printflike(1, 2);
+void	vpanic(const char *, __va_list) __dead2 __printflike(1, 0);
 
 void	cpu_boot(int);
 void	cpu_flush_dcache(void *, size_t);