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Subject[patch 12/39] hrtimer: Align the hrtimer clock bases as well
We don't use cacheline_align here because that might waste lot of
space on 32bit machine with 64 bytes cachelines and on 64bit machines
with 128 bytes cachelines.

The size of struct hrtimer_clock_base is 64byte on 64bit and 32byte on
32bit machines. So we utilize the cache lines proper.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/hrtimer.h | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

Index: tip/include/linux/hrtimer.h
===================================================================
--- tip.orig/include/linux/hrtimer.h
+++ tip/include/linux/hrtimer.h
@@ -130,6 +130,12 @@ struct hrtimer_sleeper {
struct task_struct *task;
};

+#ifdef CONFIG_64BIT
+# define HRTIMER_CLOCK_BASE_ALIGN 64
+#else
+# define HRTIMER_CLOCK_BASE_ALIGN 32
+#endif
+
/**
* struct hrtimer_clock_base - the timer base for a specific clock
* @cpu_base: per cpu clock base
@@ -147,7 +153,7 @@ struct hrtimer_clock_base {
struct timerqueue_head active;
ktime_t (*get_time)(void);
ktime_t offset;
-};
+} __attribute__((__aligned__(HRTIMER_CLOCK_BASE_ALIGN)));

enum hrtimer_base_type {
HRTIMER_BASE_MONOTONIC,
@@ -195,6 +201,8 @@ struct hrtimer_cpu_base {

static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
{
+ BUILD_BUG_ON(sizeof(struct hrtimer_clock_base) > HRTIMER_CLOCK_BASE_ALIGN);
+
timer->node.expires = time;
timer->_softexpires = time;
}



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