Re: How to write marker info in MMIO trace from kernel

[Steven Rostedt <rostedt@goodmis.org>]

On Tue, 2010-05-04 at 17:27 -0500, Larry Finger wrote:

> Thanks for the info. One other question - when I write only mmiotrace to
> the current_tracer, the trace_printk() stuff does not end up in the
> buffer. I can get it by using the "sysprof" tracer, but that has a lot
> of stuff I do not want. Did I miss some configuration? My list of
> available tracers is "blk kmemtrace mmiotrace wakeup_rt wakeup function
> sysprof sched_switch nop".

Ug, that's because the mmiotrace handles its own prints and ignores
anything it does not know about. Here, try this patch:

-- Steve

diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index 017fa37..8652f28 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -282,7 +282,7 @@ static enum print_line_t mmio_print_line(struct trace_iterator *iter)
 	case TRACE_PRINT:
 		return mmio_print_mark(iter);
 	default:
-		return TRACE_TYPE_HANDLED; /* ignore unknown entries */
+		return TRACE_TYPE_UNHANDLED;
 	}
 }