[PATCH v1 3/9] cpuidle: teo: Combine candidate state index checks against 0

From: Rafael J. Wysocki
Date: Mon Jan 13 2025 - 13:52:42 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

There are two candidate state index checks against 0 in teo_select()
that need not be separate, so combine them and update comments around
them.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---

This is a rebased variant of

https://lore.kernel.org/linux-pm/2296767.iZASKD2KPV@xxxxxxxxxxxxx/

---
drivers/cpuidle/governors/teo.c | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)

--- a/drivers/cpuidle/governors/teo.c
+++ b/drivers/cpuidle/governors/teo.c
@@ -436,24 +436,19 @@
if (idx > constraint_idx)
idx = constraint_idx;

- if (!idx && prev_intercept_idx) {
- /*
- * We have to query the sleep length here otherwise we don't
- * know after wakeup if our guess was correct.
- */
- duration_ns = tick_nohz_get_sleep_length(&delta_tick);
- cpu_data->sleep_length_ns = duration_ns;
+ if (!idx) {
+ if (prev_intercept_idx) {
+ /*
+ * Query the sleep length to be able to count the wakeup
+ * as a hit if it is caused by a timer.
+ */
+ duration_ns = tick_nohz_get_sleep_length(&delta_tick);
+ cpu_data->sleep_length_ns = duration_ns;
+ }
goto out_tick;
}

/*
- * Skip the timers check if state 0 is the current candidate one,
- * because an immediate non-timer wakeup is expected in that case.
- */
- if (!idx)
- goto out_tick;
-
- /*
* If state 0 is a polling one, check if the target residency of
* the current candidate state is low enough and skip the timers
* check in that case too.