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Subject[PATCH 1/2] cpuidle: menu: Drop redundant comparison
Date
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Since the correction factor cannot be greater than RESOLUTION * DECAY,
the result of the predicted_us computation in menu_select() cannot be
greater than data->next_timer_us, so it is not necessary to compare
the "typical interval" value coming from get_typical_interval() with
data->next_timer_us separately.

It is sufficient to copmare predicted_us with the return value of
get_typical_interval() directly, so do that and drop the now
redundant expected_interval variable.

No intentional changes of behavior.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpuidle/governors/menu.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

Index: linux-pm/drivers/cpuidle/governors/menu.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/governors/menu.c
+++ linux-pm/drivers/cpuidle/governors/menu.c
@@ -287,7 +287,6 @@ static int menu_select(struct cpuidle_dr
int i;
int idx;
unsigned int interactivity_req;
- unsigned int expected_interval;
unsigned int predicted_us;
unsigned long nr_iowaiters, cpu_load;
ktime_t delta_next;
@@ -323,14 +322,10 @@ static int menu_select(struct cpuidle_dr
predicted_us = DIV_ROUND_CLOSEST_ULL((uint64_t)data->next_timer_us *
data->correction_factor[data->bucket],
RESOLUTION * DECAY);
-
- expected_interval = get_typical_interval(data);
- expected_interval = min(expected_interval, data->next_timer_us);
-
/*
* Use the lowest expected idle interval to pick the idle state.
*/
- predicted_us = min(predicted_us, expected_interval);
+ predicted_us = min(predicted_us, get_typical_interval(data));

if (tick_nohz_tick_stopped()) {
/*
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