[PATCH] function_graph: apply tracing option 'irq-info'

[PATCH] function_graph: apply tracing option 'irq-info'

[Changbin Du]

The tracing option 'irq-info' is only used by function tracer by far. This
patch makes it also against function graph tracer. Then the two tracers
have consistent behavior of this option.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
---
 kernel/trace/trace_functions_graph.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 4a9c49c08ec9..86e410907649 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -541,7 +541,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
 		}
 
 		/* Latency format */
-		if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
+		if (tr->trace_flags & (TRACE_ITER_LATENCY_FMT | TRACE_ITER_IRQ_INFO))
 			print_graph_lat_fmt(s, ent);
 	}
 
@@ -753,7 +753,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
 	}
 
 	/* Latency format */
-	if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
+	if (tr->trace_flags & (TRACE_ITER_LATENCY_FMT | TRACE_ITER_IRQ_INFO))
 		print_graph_lat_fmt(s, ent);
 
 	return;
@@ -1135,7 +1135,7 @@ static void print_lat_header(struct seq_file *s, u32 flags)
 static void __print_graph_headers_flags(struct trace_array *tr,
 					struct seq_file *s, u32 flags)
 {
-	int lat = tr->trace_flags & TRACE_ITER_LATENCY_FMT;
+	int lat = tr->trace_flags & (TRACE_ITER_LATENCY_FMT | TRACE_ITER_IRQ_INFO);
 
 	if (lat)
 		print_lat_header(s, flags);
-- 
2.25.1

Re: [PATCH] function_graph: apply tracing option 'irq-info'

[Steven Rostedt]

On Sun, 17 May 2020 00:09:53 +0800
Changbin Du <changbin.du@gmail.com> wrote:

> The tracing option 'irq-info' is only used by function tracer by far. This
> patch makes it also against function graph tracer. Then the two tracers
> have consistent behavior of this option.
> 
> Signed-off-by: Changbin Du <changbin.du@gmail.com>
> ---

Sorry, the function graph tracer is unique, and yes, you need to enable
latency_format.

Note, irq_info is meaning less with the function_graph tracer, as it
doesn't change the latency_format with or without it.

This patch basically just makes the latency_format default for the
function_graph tracer, and changes default settings for no real advantage.
It will cause regressions.

-- Steve