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Subject: Re: [tip:tracing/urgent] tracing: Fix too large stack usage in
 do_one_initcall()
From: Steven Rostedt <srostedt@redhat.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Date: Fri, 21 Aug 2009 14:30:39 -0400
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On Fri, 2009-08-21 at 11:13 -0700, Linus Torvalds wrote:
> 
> On Fri, 21 Aug 2009, Andrew Morton wrote:
> > 
> > Do we have a max-stack-depth tracer widget btw?
> 
> Enable FTRACE and then STACK_TRACER. Then just do
> 
> 	cat /sys/kernel/debug/tracing/stack_trace
> 
> and you'll get this.

Just a nitpick, but you will want to also add "stacktrace" to the kernel
command line otherwise it is default off. If you forget to do that, you
can also enable it with /proc/sys/kernel/stack_tracer_enabled.

But if you forget what to do, the code will remind you:

[root@mxf ~]# cat /sys/kernel/debug/tracing/stack_trace 
        Depth    Size   Location    (-1 entries)
        -----    ----   --------
#
#  Stack tracer disabled
#
# To enable the stack tracer, either add 'stacktrace' to the
# kernel command line
# or 'echo 1 > /proc/sys/kernel/stack_tracer_enabled'
#


-- Steve