* [PATCH RESEND] trace: function graph: Fix filters for function_graph threshold
@ 2016-06-18 5:44 Joel Fernandes
[not found] ` <CAD=GYpbXmHhCnGWyyXQTCg6a92-NYmmNRmjRgYgfU8vpfUN_9w@mail.gmail.com>
0 siblings, 1 reply; 3+ messages in thread
From: Joel Fernandes @ 2016-06-18 5:44 UTC (permalink / raw)
To: linux-kernel; +Cc: Frederic Weisbecker, Steven Rostedt, Ingo Molnar
Function graph tracer currently ignores filters if tracing_thresh is set.
For example, even if set_ftrace_pid is set, then its ignored if tracing_thresh
set, resulting in all processes being traced.
To fix this, we reuse the same entry function as when tracing_thresh is not
set and do everything as in the regular case except for writing the function entry
to the ring buffer.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Joel Fernandes <agnel.joel@gmail.com>
---
kernel/trace/trace_functions_graph.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index a663cbb..0967fac 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -337,6 +337,13 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
if (ftrace_graph_notrace_addr(trace->func))
return 1;
+ /*
+ * Stop here if tracing_threshold is set. We only write function return
+ * events to the ring buffer.
+ */
+ if (tracing_thresh)
+ return 1;
+
local_irq_save(flags);
cpu = raw_smp_processor_id();
data = per_cpu_ptr(tr->trace_buffer.data, cpu);
@@ -354,14 +361,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
return ret;
}
-static int trace_graph_thresh_entry(struct ftrace_graph_ent *trace)
-{
- if (tracing_thresh)
- return 1;
- else
- return trace_graph_entry(trace);
-}
-
static void
__trace_graph_function(struct trace_array *tr,
unsigned long ip, unsigned long flags, int pc)
@@ -456,7 +455,7 @@ static int graph_trace_init(struct trace_array *tr)
set_graph_array(tr);
if (tracing_thresh)
ret = register_ftrace_graph(&trace_graph_thresh_return,
- &trace_graph_thresh_entry);
+ &trace_graph_entry);
else
ret = register_ftrace_graph(&trace_graph_return,
&trace_graph_entry);
--
2.5.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH RESEND] trace: function graph: Fix filters for function_graph threshold
[not found] ` <CAD=GYpbXmHhCnGWyyXQTCg6a92-NYmmNRmjRgYgfU8vpfUN_9w@mail.gmail.com>
@ 2016-06-27 15:17 ` Steven Rostedt
2016-06-27 17:14 ` Joel Fernandes
0 siblings, 1 reply; 3+ messages in thread
From: Steven Rostedt @ 2016-06-27 15:17 UTC (permalink / raw)
To: Joel Fernandes
Cc: Linux Kernel Mailing List, Frederic Weisbecker, Ingo Molnar
On Mon, 27 Jun 2016 01:25:16 -0700
Joel Fernandes <agnel.joel@gmail.com> wrote:
> Gentle ping. Could you anyone pick up this patch?
>
>
Thanks for the reminder. As this isn't a regression (it never
worked ;-) do you think this should go to the stable releases, and/or
even the current release. Or are you fine with this just going in the
next merge window?
-- Steve
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH RESEND] trace: function graph: Fix filters for function_graph threshold
2016-06-27 15:17 ` Steven Rostedt
@ 2016-06-27 17:14 ` Joel Fernandes
0 siblings, 0 replies; 3+ messages in thread
From: Joel Fernandes @ 2016-06-27 17:14 UTC (permalink / raw)
To: Steven Rostedt
Cc: Linux Kernel Mailing List, Frederic Weisbecker, Ingo Molnar
Hi Steve,
On Mon, Jun 27, 2016 at 8:17 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> On Mon, 27 Jun 2016 01:25:16 -0700
> Joel Fernandes <agnel.joel@gmail.com> wrote:
>
>> Gentle ping. Could you anyone pick up this patch?
>>
>>
>
> Thanks for the reminder. As this isn't a regression (it never
> worked ;-) do you think this should go to the stable releases, and/or
> even the current release. Or are you fine with this just going in the
> next merge window?
Queuing for the next merge window is fine with me. Thanks for picking it up.
Regards,
Joel
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2016-06-27 17:15 UTC | newest]
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2016-06-18 5:44 [PATCH RESEND] trace: function graph: Fix filters for function_graph threshold Joel Fernandes
[not found] ` <CAD=GYpbXmHhCnGWyyXQTCg6a92-NYmmNRmjRgYgfU8vpfUN_9w@mail.gmail.com>
2016-06-27 15:17 ` Steven Rostedt
2016-06-27 17:14 ` Joel Fernandes
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