[PATCH v1 4/9] cpuidle: teo: Drop local variable prev_intercept_idx

From: Rafael J. Wysocki
Date: Mon Jan 13 2025 - 13:54:04 EST


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

Local variable prev_intercept_idx in teo_select() is redundant becase
it cannot be 0 when candidate state index is 0.

The prev_intercept_idx value is the index of the deepest enabled idle
state, so if it is 0, state 0 is the deepest enabled idle state, in
which case it must be the only enabled idle state, but then teo_select()
would have returned early before initializing prev_intercept_idx.

Thus prev_intercept_idx must be nonzero and the check of it against 0
always passes, so it can be dropped altogether.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/cpuidle/governors/teo.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)

--- a/drivers/cpuidle/governors/teo.c
+++ b/drivers/cpuidle/governors/teo.c
@@ -292,7 +292,6 @@
unsigned int hit_sum = 0;
int constraint_idx = 0;
int idx0 = 0, idx = -1;
- int prev_intercept_idx;
s64 duration_ns;
int i;

@@ -370,7 +369,6 @@
* all of the deeper states, a shallower idle state is likely to be a
* better choice.
*/
- prev_intercept_idx = idx;
if (2 * idx_intercept_sum > cpu_data->total - idx_hit_sum) {
int first_suitable_idx = idx;

@@ -437,14 +435,11 @@
idx = constraint_idx;

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;
- }
+ /*
+ * Query the sleep length to be able to count the wakeup as a
+ * hit if it is caused by a timer.
+ */
+ cpu_data->sleep_length_ns = tick_nohz_get_sleep_length(&delta_tick);
goto out_tick;
}