Re: [PATCH v2 5/5] ftrace: Use preemption model accessors for trace header printout

[Steven Rostedt]

On Wed, 10 Nov 2021 20:24:48 +
Valentin Schneider  wrote:

> Per PREEMPT_DYNAMIC, checking CONFIG_PREEMPT doesn't tell you the actual
> preemption model of the live kernel. Use the newly-introduced accessors
> instead.
> 
> Signed-off-by: Valentin Schneider 
> ---
>  kernel/trace/trace.c | 14 --
>  1 file changed, 4 insertions(+), 10 deletions(-)

Reviewed-by: Steven Rostedt (VMware) 

-- Steve

[PATCH v2 5/5] ftrace: Use preemption model accessors for trace header printout

[Valentin Schneider]

Per PREEMPT_DYNAMIC, checking CONFIG_PREEMPT doesn't tell you the actual
preemption model of the live kernel. Use the newly-introduced accessors
instead.

Signed-off-by: Valentin Schneider 
---
 kernel/trace/trace.c | 14 --
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7896d30d90f7..71f293569ed0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4271,17 +4271,11 @@ print_trace_header(struct seq_file *m, struct 
trace_iterator *iter)
   entries,
   total,
   buf->cpu,
-#if defined(CONFIG_PREEMPT_NONE)
-  "server",
-#elif defined(CONFIG_PREEMPT_VOLUNTARY)
-  "desktop",
-#elif defined(CONFIG_PREEMPT)
-  "preempt",
-#elif defined(CONFIG_PREEMPT_RT)
-  "preempt_rt",
-#else
+  is_preempt_none()  ? "server" :
+  is_preempt_voluntary() ? "desktop" :
+  is_preempt_full()  ? "preempt" :
+  is_preempt_rt()? "preempt_rt" :
   "unknown",
-#endif
   /* These are reserved for later use */
   0, 0, 0, 0);
 #ifdef CONFIG_SMP
-- 
2.25.1