[PATCH] hrtimers: remove data field

The nanosleep cleanup allows to remove the data field of hrtimer.  The
callback function can use container_of() to get it's own data.  Since the
hrtimer structure is anyway embedded in other structures, this adds no
overhead.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 17 insertions, 21 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index a02063903aa..4bd6486aa67 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -848,7 +848,7 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts
 	hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_REL);
 	sig->it_real_incr.tv64 = 0;
 	sig->real_timer.function = it_real_fn;
-	sig->real_timer.data = tsk;
+	sig->tsk = tsk;
 
 	sig->it_virt_expires = cputime_zero;
 	sig->it_virt_incr = cputime_zero;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 44108de4f02..0237a556eb1 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -613,21 +613,19 @@ static inline void run_hrtimer_queue(struct hrtimer_base *base)
 
 	while ((node = base->first)) {
 		struct hrtimer *timer;
-		int (*fn)(void *);
+		int (*fn)(struct hrtimer *);
 		int restart;
-		void *data;
 
 		timer = rb_entry(node, struct hrtimer, node);
 		if (base->softirq_time.tv64 <= timer->expires.tv64)
 			break;
 
 		fn = timer->function;
-		data = timer->data;
 		set_curr_timer(base, timer);
 		__remove_hrtimer(timer, base);
 		spin_unlock_irq(&base->lock);
 
-		restart = fn(data);
+		restart = fn(timer);
 
 		spin_lock_irq(&base->lock);
 
@@ -664,9 +662,10 @@ struct sleep_hrtimer {
 	int expired;
 };
 
-static int nanosleep_wakeup(void *data)
+static int nanosleep_wakeup(struct hrtimer *timer)
 {
-	struct sleep_hrtimer *t = data;
+	struct sleep_hrtimer *t =
+		container_of(timer, struct sleep_hrtimer, timer);
 
 	t->expired = 1;
 	wake_up_process(t->task);
@@ -677,7 +676,6 @@ static int nanosleep_wakeup(void *data)
 static int __sched do_nanosleep(struct sleep_hrtimer *t, enum hrtimer_mode mode)
 {
 	t->timer.function = nanosleep_wakeup;
-	t->timer.data = t;
 	t->task = current;
 	t->expired = 0;
 
diff --git a/kernel/itimer.c b/kernel/itimer.c
index af2ec6b4392..204ed7939e7 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -128,17 +128,16 @@ asmlinkage long sys_getitimer(int which, struct itimerval __user *value)
 /*
  * The timer is automagically restarted, when interval != 0
  */
-int it_real_fn(void *data)
+int it_real_fn(struct hrtimer *timer)
 {
-	struct task_struct *tsk = (struct task_struct *) data;
+	struct signal_struct *sig =
+	    container_of(timer, struct signal_struct, real_timer);
 
-	send_group_sig_info(SIGALRM, SEND_SIG_PRIV, tsk);
-
-	if (tsk->signal->it_real_incr.tv64 != 0) {
-		hrtimer_forward(&tsk->signal->real_timer,
-				tsk->signal->real_timer.base->softirq_time,
-				tsk->signal->it_real_incr);
+	send_group_sig_info(SIGALRM, SEND_SIG_PRIV, sig->tsk);
 
+	if (sig->it_real_incr.tv64 != 0) {
+		hrtimer_forward(timer, timer->base->softirq_time,
+				sig->it_real_incr);
 		return HRTIMER_RESTART;
 	}
 	return HRTIMER_NORESTART;
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 7c5f44787c8..ac6dc874442 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -145,7 +145,7 @@ static int common_timer_set(struct k_itimer *, int,
 			    struct itimerspec *, struct itimerspec *);
 static int common_timer_del(struct k_itimer *timer);
 
-static int posix_timer_fn(void *data);
+static int posix_timer_fn(struct hrtimer *data);
 
 static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags);
 
@@ -334,14 +334,14 @@ EXPORT_SYMBOL_GPL(posix_timer_event);
 
  * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
  */
-static int posix_timer_fn(void *data)
+static int posix_timer_fn(struct hrtimer *timer)
 {
-	struct k_itimer *timr = data;
-	struct hrtimer *timer = &timr->it.real.timer;
+	struct k_itimer *timr;
 	unsigned long flags;
 	int si_private = 0;
 	int ret = HRTIMER_NORESTART;
 
+	timr = container_of(timer, struct k_itimer, it.real.timer);
 	spin_lock_irqsave(&timr->it_lock, flags);
 
 	if (timr->it.real.interval.tv64 != 0)
@@ -725,7 +725,6 @@ common_timer_set(struct k_itimer *timr, int flags,
 
 	mode = flags & TIMER_ABSTIME ? HRTIMER_ABS : HRTIMER_REL;
 	hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
-	timr->it.real.timer.data = timr;
 	timr->it.real.timer.function = posix_timer_fn;
 
 	timer->expires = timespec_to_ktime(new_setting->it_value);