[PATCH] ftrace: print lazy preemption model

From: Shrikanth Hegde
Date: Fri Jan 03 2025 - 04:37:28 EST


Print lazy preemption model in ftrace header when latency-format=1.

cat /sys/kernel/debug/sched/preempt
none voluntary full (lazy)

Without patch:
latency: 0 us, #232946/232946, CPU#40 | (M:unknown VP:0, KP:0, SP:0 HP:0 #P:80)
With Patch:
latency: 0 us, #1897938/25566788, CPU#16 | (M:lazy VP:0, KP:0, SP:0 HP:0 #P:80)

Signed-off-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxx>
---
kernel/trace/trace.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f8aebcb01e62..b6e40e8791fa 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4122,6 +4122,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
preempt_model_none() ? "server" :
preempt_model_voluntary() ? "desktop" :
preempt_model_full() ? "preempt" :
+ preempt_model_lazy() ? "lazy" :
preempt_model_rt() ? "preempt_rt" :
"unknown",
/* These are reserved for later use */
--
2.39.3