Re: [BUG?] tracing/function_graph: set_graph_function was brokenfrom 2.6.36-rc2
From: Steven Rostedt
Date: Fri Jan 21 2011 - 13:40:51 EST
On Fri, 2011-01-21 at 17:27 +0800, wu zhangjin wrote:
> On Fri, Jan 21, 2011 at 1:30 AM, Steven Rostedt <srostedt@xxxxxxxxxx> wrote:
> >> trace_graph_entry():
> >>
> >> [snip]
> >> /* trace it when it is-nested-in or is a function enabled. */
> >> if (!(trace->depth || ftrace_graph_addr(trace->func)) ||
> >> ftrace_graph_ignore_irqs())
> >> return 0;
> >> [snip]
> >>
>
> By default, ftrace_graph_ignore_irqs() is false, then, if we don't put
> 0 to /debug/tracing/options/funcgraph-irqs, it will not return even if
> we have specified some entries through the tracing/set_graph_function
> interface, as a result, every function will be traced and it doesn't
> work as we expected, the expected result is only the specified
> functions are reserved in the tracing result.
>
???
It's an or, if the first case is true:
!(trace->depth || ftrace_graph_addr(trace->func))
then we return and do not trace. Regardless of what
ftrace_graph_ignore_irqs() is set to.
Can you show me an example of what you are having a problem with?
-- Steve
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/