Commit b9a6af26 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

cpuidle: teo: Drop local variable prev_intercept_idx 



Local variable prev_intercept_idx in teo_select() is redundant because
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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarChristian Loehle <christian.loehle@arm.com>
Tested-by: default avatarAboorva Devarajan <aboorvad@linux.ibm.com>
Tested-by: default avatarChristian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/3327997.aeNJFYEL58@rjwysocki.net


[ rjw: Fixed typo in the changelog ]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent ea185406

drivers/cpuidle/governors/teo.c

+5 −10
Original line number Diff line number Diff line
@@ -292,7 +292,6 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, 
	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 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, 
	 * 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 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, 
		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.

		 * 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;

		}

		cpu_data->sleep_length_ns = tick_nohz_get_sleep_length(&delta_tick);

		goto out_tick;

	}