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Date:   Fri, 16 Nov 2018 15:49:26 -0700
From:   Keith Busch <keith.busch@intel.com>
To:     Timur Tabi <timur@kernel.org>
Cc:     lkml <linux-kernel@vger.kernel.org>
Subject: Re: Enable tracing only for one function and its children?
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On Fri, Nov 16, 2018 at 04:37:55PM -0600, Timur Tabi wrote:
> Is there a way to enable ftrace tracing only for one specific function
> and all the functions it calls?  Then when the function returns,
> disable tracing until the next time?
> 
> When I pass the function name only to set_ftrace_filter, it literally
> only traces that function, which doesn't help me.  

I think you're looking for the set_graph_function option for the
function_graph tracer.