[PATCH] i386: multi-column stack backtraces

Print stack backtraces in multiple columns, saving screen space.  Number of
columns is configurable and defaults to one so behavior is
backwards-compatible.

Also removes the brackets around addresses when printing more
that one entry per line so they print as:
    <address>
instead of:
    [<address>]
This helps multiple entries fit better on one line.

Original idea by Dave Jones, taken from x86_64.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/Kconfig.debug b/arch/i386/Kconfig.debug
index bf32ecc..00108ba 100644
--- a/arch/i386/Kconfig.debug
+++ b/arch/i386/Kconfig.debug
@@ -31,6 +31,15 @@
 
 	  This option will slow down process creation somewhat.
 
+config STACK_BACKTRACE_COLS
+	int "Stack backtraces per line" if DEBUG_KERNEL
+	range 1 3
+	default 2
+	help
+	  Selects how many stack backtrace entries per line to display.
+
+	  This can save screen space when displaying traces.
+
 comment "Page alloc debug is incompatible with Software Suspend on i386"
 	depends on DEBUG_KERNEL && SOFTWARE_SUSPEND