Re: [PATCH] tracing: Increase stack skip on event trigger

From: Steven Rostedt
Date: Mon Apr 13 2015 - 18:06:15 EST


On Thu, 26 Mar 2015 09:39:23 +0900
Namhyung Kim <namhyung@xxxxxxxxxx> wrote:

> When 'stacktrace' trigger is used for event tracing, it should skip 4
> functions instead of 3. Otherwise it'll contain ftrace_raw_event_XXX
> like below:
>
> # echo stacktrace > events/sched/sched_switch/trigger
> # tail trace
> => rcu_gp_kthread
> => kthread
> => ret_from_fork
> ksoftirqd/0-3 [000] d..3 53.343993: <stack trace>
> => ftrace_raw_event_sched_switch
> => __schedule
> => schedule
> => smpboot_thread_fn
> => kthread
> => ret_from_fork
>
> Reported-by: Minchan Kim <minchan@xxxxxxxxxx>
> Cc: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---

Hmm, this breaks when frame pointers are not enabled.

I may come up with something though.

-- Steve
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