[patch 01/20] timer: Make pinned a timer property

From: Thomas Gleixner
Date: Mon Jun 13 2016 - 04:43:07 EST


We want to move the timer migration from a push to a pull model. This requires
to store the pinned attribute of a timer in the timer itself. This must happen
at initialization time.

Add the helper macros for this.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
include/linux/timer.h | 25 ++++++++++++++++++++++---
kernel/time/timer.c | 10 +++++-----
2 files changed, 27 insertions(+), 8 deletions(-)

Index: b/include/linux/timer.h
===================================================================
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -62,7 +62,8 @@ struct timer_list {
#define TIMER_MIGRATING 0x00080000
#define TIMER_BASEMASK (TIMER_CPUMASK | TIMER_MIGRATING)
#define TIMER_DEFERRABLE 0x00100000
-#define TIMER_IRQSAFE 0x00200000
+#define TIMER_PINNED 0x00200000
+#define TIMER_IRQSAFE 0x00400000

#define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
.entry = { .next = TIMER_ENTRY_STATIC }, \
@@ -78,9 +79,15 @@ struct timer_list {
#define TIMER_INITIALIZER(_function, _expires, _data) \
__TIMER_INITIALIZER((_function), (_expires), (_data), 0)

+#define TIMER_PINNED_INITIALIZER(_function, _expires, _data) \
+ __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_PINNED)
+
#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) \
__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)

+#define TIMER_PINNED_DEFERRED_INITIALIZER(_function, _expires, _data) \
+ __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE | TIMER_PINNED)
+
#define DEFINE_TIMER(_name, _function, _expires, _data) \
struct timer_list _name = \
TIMER_INITIALIZER(_function, _expires, _data)
@@ -124,8 +131,12 @@ static inline void init_timer_on_stack_k

#define init_timer(timer) \
__init_timer((timer), 0)
+#define init_timer_pinned(timer) \
+ __init_timer((timer), TIMER_PINNED)
#define init_timer_deferrable(timer) \
__init_timer((timer), TIMER_DEFERRABLE)
+#define init_timer_pinned_deferrable(timer) \
+ __init_timer((timer), TIMER_DEFERRABLE | TIMER_PINNED)
#define init_timer_on_stack(timer) \
__init_timer_on_stack((timer), 0)

@@ -145,12 +156,20 @@ static inline void init_timer_on_stack_k

#define setup_timer(timer, fn, data) \
__setup_timer((timer), (fn), (data), 0)
+#define setup_pinned_timer(timer, fn, data) \
+ __setup_timer((timer), (fn), (data), TIMER_PINNED)
#define setup_deferrable_timer(timer, fn, data) \
__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
+#define setup_pinned_deferrable_timer(timer, fn, data) \
+ __setup_timer((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
#define setup_timer_on_stack(timer, fn, data) \
__setup_timer_on_stack((timer), (fn), (data), 0)
+#define setup_pinned_timer_on_stack(timer, fn, data) \
+ __setup_timer_on_stack((timer), (fn), (data), TIMER_PINNED)
#define setup_deferrable_timer_on_stack(timer, fn, data) \
__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
+#define setup_pinned_deferrable_timer_on_stack(timer, fn, data) \
+ __setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)

/**
* timer_pending - is a timer pending?
@@ -175,8 +194,8 @@ extern int mod_timer_pinned(struct timer

extern void set_timer_slack(struct timer_list *time, int slack_hz);

-#define TIMER_NOT_PINNED 0
-#define TIMER_PINNED 1
+#define MOD_TIMER_NOT_PINNED 0
+#define MOD_TIMER_PINNED 1
/*
* The jiffies value which is added to now, when there is no timer
* in the timer wheel:
Index: b/kernel/time/timer.c
===================================================================
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -782,7 +782,7 @@ static inline int

debug_activate(timer, expires);

- new_base = get_target_base(base, pinned);
+ new_base = get_target_base(base, pinned || timer->flags & TIMER_PINNED);

if (base != new_base) {
/*
@@ -825,7 +825,7 @@ static inline int
*/
int mod_timer_pending(struct timer_list *timer, unsigned long expires)
{
- return __mod_timer(timer, expires, true, TIMER_NOT_PINNED);
+ return __mod_timer(timer, expires, true, MOD_TIMER_NOT_PINNED);
}
EXPORT_SYMBOL(mod_timer_pending);

@@ -900,7 +900,7 @@ int mod_timer(struct timer_list *timer,
if (timer_pending(timer) && timer->expires == expires)
return 1;

- return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
+ return __mod_timer(timer, expires, false, MOD_TIMER_NOT_PINNED);
}
EXPORT_SYMBOL(mod_timer);

@@ -928,7 +928,7 @@ int mod_timer_pinned(struct timer_list *
if (timer->expires == expires && timer_pending(timer))
return 1;

- return __mod_timer(timer, expires, false, TIMER_PINNED);
+ return __mod_timer(timer, expires, false, MOD_TIMER_PINNED);
}
EXPORT_SYMBOL(mod_timer_pinned);

@@ -1512,7 +1512,7 @@ signed long __sched schedule_timeout(sig
expire = timeout + jiffies;

setup_timer_on_stack(&timer, process_timeout, (unsigned long)current);
- __mod_timer(&timer, expire, false, TIMER_NOT_PINNED);
+ __mod_timer(&timer, expire, false, MOD_TIMER_NOT_PINNED);
schedule();
del_singleshot_timer_sync(&timer);