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-rw-r--r--include/linux/hrtimer.h8
-rw-r--r--include/linux/hrtimer_types.h3
2 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index b5003856fd60..c924bb2498db 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -31,6 +31,13 @@
* soft irq context
* HRTIMER_MODE_HARD - Timer callback function will be executed in
* hard irq context even on PREEMPT_RT.
+ * HRTIMER_MODE_LAZY_REARM - Avoid reprogramming if the timer was the
+ * first expiring timer and is moved into the
+ * future. Special mode for the HRTICK timer to
+ * avoid extensive reprogramming of the hardware,
+ * which is expensive in virtual machines. Risks
+ * a pointless expiry, but that's better than
+ * reprogramming on every context switch,
*/
enum hrtimer_mode {
HRTIMER_MODE_ABS = 0x00,
@@ -38,6 +45,7 @@ enum hrtimer_mode {
HRTIMER_MODE_PINNED = 0x02,
HRTIMER_MODE_SOFT = 0x04,
HRTIMER_MODE_HARD = 0x08,
+ HRTIMER_MODE_LAZY_REARM = 0x10,
HRTIMER_MODE_ABS_PINNED = HRTIMER_MODE_ABS | HRTIMER_MODE_PINNED,
HRTIMER_MODE_REL_PINNED = HRTIMER_MODE_REL | HRTIMER_MODE_PINNED,
diff --git a/include/linux/hrtimer_types.h b/include/linux/hrtimer_types.h
index 8fbbb6bdf7a1..64381c64cdbd 100644
--- a/include/linux/hrtimer_types.h
+++ b/include/linux/hrtimer_types.h
@@ -33,6 +33,8 @@ enum hrtimer_restart {
* @is_soft: Set if hrtimer will be expired in soft interrupt context.
* @is_hard: Set if hrtimer will be expired in hard interrupt context
* even on RT.
+ * @is_lazy: Set if the timer is frequently rearmed to avoid updates
+ * of the clock event device
*
* The hrtimer structure must be initialized by hrtimer_setup()
*/
@@ -45,6 +47,7 @@ struct hrtimer {
u8 is_rel;
u8 is_soft;
u8 is_hard;
+ u8 is_lazy;
};
#endif /* _LINUX_HRTIMER_TYPES_H */