[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>

diff --git a/fs/exec.c b/fs/exec.c
index 995cba3..c7397c4 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -632,7 +632,7 @@ static int de_thread(struct task_struct *tsk)
                 * synchronize with any firing (by calling del_timer_sync)
                 * before we can safely let the old group leader die.
                 */
-               sig->real_timer.data = current;
+               sig->tsk = current;
                spin_unlock_irq(lock);
                if (hrtimer_cancel(&sig->real_timer))
                        hrtimer_restart(&sig->real_timer);

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index f57cc7b..9383015 100644 (file)
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -45,9 +45,7 @@ struct hrtimer_base;
  * @expires:   the absolute expiry time in the hrtimers internal
  *             representation. The time is related to the clock on
  *             which the timer is based.
- * @state:     state of the timer
  * @function:  timer expiry callback function
- * @data:      argument for the callback function
  * @base:      pointer to the timer base (per cpu and per clock)
  *
  * The hrtimer structure must be initialized by init_hrtimer_#CLOCKTYPE()
@@ -55,8 +53,7 @@ struct hrtimer_base;
 struct hrtimer {
        struct rb_node          node;
        ktime_t                 expires;
-       int                     (*function)(void *);
-       void                    *data;
+       int                     (*function)(struct hrtimer *);
        struct hrtimer_base     *base;
 };
 

diff --git a/include/linux/sched.h b/include/linux/sched.h
index e0054c1..036d14d 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -402,6 +402,7 @@ struct signal_struct {
 
        /* ITIMER_REAL timer for the process */
        struct hrtimer real_timer;
+       struct task_struct *tsk;
        ktime_t it_real_incr;
 
        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */

diff --git a/include/linux/timer.h b/include/linux/timer.h
index ee5a09e..b5caabc 100644 (file)
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -96,6 +96,7 @@ static inline void add_timer(struct timer_list *timer)
 
 extern void init_timers(void);
 extern void run_local_timers(void);
-extern int it_real_fn(void *);
+struct hrtimer;
+extern int it_real_fn(struct hrtimer *);
 
 #endif

diff --git a/kernel/fork.c b/kernel/fork.c
index a020639..4bd6486 100644 (file)
--- 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 44108de..0237a55 100644 (file)
--- 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 af2ec6b..204ed79 100644 (file)
--- 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 7c5f447..ac6dc87 100644 (file)
--- 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);