The patch titled
drivers/cpuidle/governors/menu.c: fix undefined reference to `__udivdi3'
has been added to the -mm tree. Its filename is
drivers-cpuidle-governors-menuc-fix-undefined-reference-to-__udivdi3.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: drivers/cpuidle/governors/menu.c: fix undefined reference to `__udivdi3'
From: Stephen Hemminger <shemminger@xxxxxxxxxxxxxxxxxxxx>
menu: use proper 64 bit math
The new menu governor is incorrectly doing a 64 bit divide. Compile
tested only
Signed-off-by: Stephen Hemminger <shemminger@xxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Len Brown <len.brown@xxxxxxxxx>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/cpuidle/governors/menu.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff -puN drivers/cpuidle/governors/menu.c~drivers-cpuidle-governors-menuc-fix-undefined-reference-to-__udivdi3 drivers/cpuidle/governors/menu.c
--- a/drivers/cpuidle/governors/menu.c~drivers-cpuidle-governors-menuc-fix-undefined-reference-to-__udivdi3
+++ a/drivers/cpuidle/governors/menu.c
@@ -18,6 +18,7 @@
#include <linux/hrtimer.h>
#include <linux/tick.h>
#include <linux/sched.h>
+#include <linux/math64.h>
#define BUCKETS 12
#define RESOLUTION 1024
@@ -169,6 +170,12 @@ static DEFINE_PER_CPU(struct menu_device
static void menu_update(struct cpuidle_device *dev);
+/* This implements DIV_ROUND_CLOSEST but avoids 64 bit division */
+static u64 div_round64(u64 dividend, u32 divisor)
+{
+ return div_u64(dividend + (divisor / 2), divisor);
+}
+
/**
* menu_select - selects the next idle state to enter
* @dev: the CPU
@@ -209,9 +216,8 @@ static int menu_select(struct cpuidle_de
data->correction_factor[data->bucket] = RESOLUTION * DECAY;
/* Make sure to round up for half microseconds */
- data->predicted_us = DIV_ROUND_CLOSEST(
- data->expected_us * data->correction_factor[data->bucket],
- RESOLUTION * DECAY);
+ data->predicted_us = div_round64(data->expected_us * data->correction_factor[data->bucket],
+ RESOLUTION * DECAY);
/*
* We want to default to C1 (hlt), not to busy polling
_
Patches currently in -mm which might be from shemminger@xxxxxxxxxxxxxxxxxxxx are
drivers-cpuidle-governors-menuc-fix-undefined-reference-to-__udivdi3.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
