[tip:timers/core] timers: Make 'pinned' a timer property
From: tip-bot for Thomas Gleixner
Date: Thu Jul 07 2016 - 04:40:52 EST
Commit-ID: e675447bda51c1ea72d1ac9132ce3bed974f1da3
Gitweb: http://git.kernel.org/tip/e675447bda51c1ea72d1ac9132ce3bed974f1da3
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Mon, 4 Jul 2016 09:50:15 +0000
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 7 Jul 2016 10:25:13 +0200
timers: Make 'pinned' a timer property
We want to move the timer migration logic from a 'push' to a 'pull' model.
Under the current 'push' model pinned timers are handled via
a runtime API variant: mod_timer_pinned().
The 'pull' model requires us to store the pinned attribute of a timer
in the timer_list structure itself, as a new TIMER_PINNED bit in
timer->flags.
This flag must be set at initialization time and the timer APIs
recognize the flag.
This patch:
- Implements the new flag and associated new-style initialization
methods
- makes mod_timer() recognize new-style pinned timers,
- and adds some migration helper facility to allow
step by step conversion of old-style to new-style
pinned timers.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxx>
Cc: Chris Mason <clm@xxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: George Spelvin <linux@xxxxxxxxxxxxxxxxxxx>
Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: rt@xxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20160704094341.049338558@xxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
include/linux/timer.h | 25 ++++++++++++++++++++++---
kernel/time/timer.c | 10 +++++-----
2 files changed, 27 insertions(+), 8 deletions(-)
diff --git a/include/linux/timer.h b/include/linux/timer.h
index 20ac746..046d6cf 100644
--- 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_key(struct timer_list *timer,
#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_key(struct timer_list *timer,
#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_list *timer, unsigned long expires);
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:
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 3a95f97..693f6d1 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -782,7 +782,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
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 @@ out_unlock:
*/
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, unsigned long expires)
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 *timer, unsigned long expires)
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(signed long timeout)
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);