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-rw-r--r--drivers/cpuidle/governors/menu.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 68104434ebb5..73655aeb3a60 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -18,6 +18,7 @@
18#include <linux/hrtimer.h> 18#include <linux/hrtimer.h>
19#include <linux/tick.h> 19#include <linux/tick.h>
20#include <linux/sched.h> 20#include <linux/sched.h>
21#include <linux/math64.h>
21 22
22#define BUCKETS 12 23#define BUCKETS 12
23#define RESOLUTION 1024 24#define RESOLUTION 1024
@@ -169,6 +170,12 @@ static DEFINE_PER_CPU(struct menu_device, menu_devices);
169 170
170static void menu_update(struct cpuidle_device *dev); 171static void menu_update(struct cpuidle_device *dev);
171 172
173/* This implements DIV_ROUND_CLOSEST but avoids 64 bit division */
174static u64 div_round64(u64 dividend, u32 divisor)
175{
176 return div_u64(dividend + (divisor / 2), divisor);
177}
178
172/** 179/**
173 * menu_select - selects the next idle state to enter 180 * menu_select - selects the next idle state to enter
174 * @dev: the CPU 181 * @dev: the CPU
@@ -209,9 +216,8 @@ static int menu_select(struct cpuidle_device *dev)
209 data->correction_factor[data->bucket] = RESOLUTION * DECAY; 216 data->correction_factor[data->bucket] = RESOLUTION * DECAY;
210 217
211 /* Make sure to round up for half microseconds */ 218 /* Make sure to round up for half microseconds */
212 data->predicted_us = DIV_ROUND_CLOSEST( 219 data->predicted_us = div_round64(data->expected_us * data->correction_factor[data->bucket],
213 data->expected_us * data->correction_factor[data->bucket], 220 RESOLUTION * DECAY);
214 RESOLUTION * DECAY);
215 221
216 /* 222 /*
217 * We want to default to C1 (hlt), not to busy polling 223 * We want to default to C1 (hlt), not to busy polling