[patch 27/46] hrtimers: clean up callback tracking

Thomas Gleixner
2007-01-23T22:10:24Z

[-- Attachment #1: hrtimers-clean-up-callback-tracking.patch --]
[-- Type: text/plain, Size: 2835 bytes --]

From: Thomas Gleixner <tglx@linutronix.de>

Reintroduce ktimers feature "optimized away" by the ktimers review
process: remove the curr_timer pointer from the cpu-base and use the
hrtimer state.

No functional changes.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

include/linux/hrtimer.h | 1 -
kernel/hrtimer.c | 10 +---------
2 files changed, 1 insertion(+), 10 deletions(-)

Index: linux-2.6.20-rc4-mm1-bo/include/linux/hrtimer.h
===================================================================
--- linux-2.6.20-rc4-mm1-bo.orig/include/linux/hrtimer.h
+++ linux-2.6.20-rc4-mm1-bo/include/linux/hrtimer.h
@@ -136,7 +136,6 @@ struct hrtimer_cpu_base {
spinlock_t lock;
struct lock_class_key lock_key;
struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES];
- struct hrtimer *curr_timer;
};

/*
Index: linux-2.6.20-rc4-mm1-bo/kernel/hrtimer.c
===================================================================
--- linux-2.6.20-rc4-mm1-bo.orig/kernel/hrtimer.c
+++ linux-2.6.20-rc4-mm1-bo/kernel/hrtimer.c
@@ -172,8 +172,6 @@ static inline int hrtimer_callback_runni
*/
#ifdef CONFIG_SMP

-#define set_curr_timer(b, t) do { (b)->curr_timer = (t); } while (0)
-
/*
* We are using hashed locking: holding per_cpu(hrtimer_bases)[n].lock
* means that all timers which are tied to this base via timer->base are
@@ -227,7 +225,7 @@ switch_hrtimer_base(struct hrtimer *time
* completed. There is no conflict as we hold the lock until
* the timer is enqueued.
*/
- if (unlikely(base->cpu_base->curr_timer == timer))
+ if (unlikely(timer->state & HRTIMER_STATE_CALLBACK))
return base;

/* See the comment in lock_timer_base() */
@@ -241,8 +239,6 @@ switch_hrtimer_base(struct hrtimer *time

#else /* CONFIG_SMP */

-#define set_curr_timer(b, t) do { } while (0)
-
static inline struct hrtimer_clock_base *
lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
{
@@ -670,7 +666,6 @@ static inline void run_hrtimer_queue(str
break;

fn = timer->function;
- set_curr_timer(cpu_base, timer);
__remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK);
spin_unlock_irq(&cpu_base->lock);

@@ -684,7 +679,6 @@ static inline void run_hrtimer_queue(str
enqueue_hrtimer(timer, base);
}
}
- set_curr_timer(cpu_base, NULL);
spin_unlock_irq(&cpu_base->lock);
}

@@ -871,8 +865,6 @@ static void migrate_hrtimers(int cpu)
spin_lock(&old_base->lock);

for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- BUG_ON(old_base->curr_timer);
-
migrate_hrtimer_list(&old_base->clock_base[i],
&new_base->clock_base[i]);
}

--