]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - kernel/hrtimer.c
hrtimer: convert powerpc/oprofile to the new hrtimer apis
[linux-2.6-omap-h63xx.git] / kernel / hrtimer.c
index e379ef0e9c20c5e77b0003398e46eb859c6399e3..ae307feec74c2435c62f0ab6214aeecd33e6eca6 100644 (file)
@@ -43,6 +43,7 @@
 #include <linux/tick.h>
 #include <linux/seq_file.h>
 #include <linux/err.h>
+#include <linux/debugobjects.h>
 
 #include <asm/uaccess.h>
 
@@ -152,15 +153,6 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
                ktime_add(xtim, tomono);
 }
 
-/*
- * Helper function to check, whether the timer is running the callback
- * function
- */
-static inline int hrtimer_callback_running(struct hrtimer *timer)
-{
-       return timer->state & HRTIMER_STATE_CALLBACK;
-}
-
 /*
  * Functions and macros which are different for UP/SMP systems are kept in a
  * single place
@@ -308,11 +300,10 @@ EXPORT_SYMBOL_GPL(ktime_sub_ns);
  */
 u64 ktime_divns(const ktime_t kt, s64 div)
 {
-       u64 dclc, inc, dns;
+       u64 dclc;
        int sft = 0;
 
-       dclc = dns = ktime_to_ns(kt);
-       inc = div;
+       dclc = ktime_to_ns(kt);
        /* Make sure the divisor is less than 2^32: */
        while (div >> 32) {
                sft++;
@@ -342,6 +333,115 @@ ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs)
        return res;
 }
 
+#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
+
+static struct debug_obj_descr hrtimer_debug_descr;
+
+/*
+ * fixup_init is called when:
+ * - an active object is initialized
+ */
+static int hrtimer_fixup_init(void *addr, enum debug_obj_state state)
+{
+       struct hrtimer *timer = addr;
+
+       switch (state) {
+       case ODEBUG_STATE_ACTIVE:
+               hrtimer_cancel(timer);
+               debug_object_init(timer, &hrtimer_debug_descr);
+               return 1;
+       default:
+               return 0;
+       }
+}
+
+/*
+ * fixup_activate is called when:
+ * - an active object is activated
+ * - an unknown object is activated (might be a statically initialized object)
+ */
+static int hrtimer_fixup_activate(void *addr, enum debug_obj_state state)
+{
+       switch (state) {
+
+       case ODEBUG_STATE_NOTAVAILABLE:
+               WARN_ON_ONCE(1);
+               return 0;
+
+       case ODEBUG_STATE_ACTIVE:
+               WARN_ON(1);
+
+       default:
+               return 0;
+       }
+}
+
+/*
+ * fixup_free is called when:
+ * - an active object is freed
+ */
+static int hrtimer_fixup_free(void *addr, enum debug_obj_state state)
+{
+       struct hrtimer *timer = addr;
+
+       switch (state) {
+       case ODEBUG_STATE_ACTIVE:
+               hrtimer_cancel(timer);
+               debug_object_free(timer, &hrtimer_debug_descr);
+               return 1;
+       default:
+               return 0;
+       }
+}
+
+static struct debug_obj_descr hrtimer_debug_descr = {
+       .name           = "hrtimer",
+       .fixup_init     = hrtimer_fixup_init,
+       .fixup_activate = hrtimer_fixup_activate,
+       .fixup_free     = hrtimer_fixup_free,
+};
+
+static inline void debug_hrtimer_init(struct hrtimer *timer)
+{
+       debug_object_init(timer, &hrtimer_debug_descr);
+}
+
+static inline void debug_hrtimer_activate(struct hrtimer *timer)
+{
+       debug_object_activate(timer, &hrtimer_debug_descr);
+}
+
+static inline void debug_hrtimer_deactivate(struct hrtimer *timer)
+{
+       debug_object_deactivate(timer, &hrtimer_debug_descr);
+}
+
+static inline void debug_hrtimer_free(struct hrtimer *timer)
+{
+       debug_object_free(timer, &hrtimer_debug_descr);
+}
+
+static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+                          enum hrtimer_mode mode);
+
+void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
+                          enum hrtimer_mode mode)
+{
+       debug_object_init_on_stack(timer, &hrtimer_debug_descr);
+       __hrtimer_init(timer, clock_id, mode);
+}
+
+void destroy_hrtimer_on_stack(struct hrtimer *timer)
+{
+       debug_object_free(timer, &hrtimer_debug_descr);
+}
+
+#else
+static inline void debug_hrtimer_init(struct hrtimer *timer) { }
+static inline void debug_hrtimer_activate(struct hrtimer *timer) { }
+static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
+#endif
+
 /*
  * Check, whether the timer is on the callback pending list
  */
@@ -417,7 +517,7 @@ static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
                if (!base->first)
                        continue;
                timer = rb_entry(base->first, struct hrtimer, node);
-               expires = ktime_sub(timer->expires, base->offset);
+               expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
                if (expires.tv64 < cpu_base->expires_next.tv64)
                        cpu_base->expires_next = expires;
        }
@@ -439,10 +539,10 @@ static int hrtimer_reprogram(struct hrtimer *timer,
                             struct hrtimer_clock_base *base)
 {
        ktime_t *expires_next = &__get_cpu_var(hrtimer_bases).expires_next;
-       ktime_t expires = ktime_sub(timer->expires, base->offset);
+       ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
        int res;
 
-       WARN_ON_ONCE(timer->expires.tv64 < 0);
+       WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0);
 
        /*
         * When the callback is running, we do not reprogram the clock event
@@ -522,7 +622,7 @@ static void retrigger_next_event(void *arg)
 void clock_was_set(void)
 {
        /* Retrigger the CPU local events everywhere */
-       on_each_cpu(retrigger_next_event, NULL, 0, 1);
+       on_each_cpu(retrigger_next_event, NULL, 1);
 }
 
 /*
@@ -531,8 +631,6 @@ void clock_was_set(void)
  */
 void hres_timers_resume(void)
 {
-       WARN_ON_ONCE(num_online_cpus() > 1);
-
        /* Retrigger the CPU local events: */
        retrigger_next_event(NULL);
 }
@@ -567,6 +665,7 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
                /* Timer is expired, act upon the callback mode */
                switch(timer->cb_mode) {
                case HRTIMER_CB_IRQSAFE_NO_RESTART:
+                       debug_hrtimer_deactivate(timer);
                        /*
                         * We can call the callback from here. No restart
                         * happens, so no danger of recursion
@@ -581,6 +680,7 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
                         * the tick timer in the softirq ! The calling site
                         * takes care of this.
                         */
+                       debug_hrtimer_deactivate(timer);
                        return 1;
                case HRTIMER_CB_IRQSAFE:
                case HRTIMER_CB_SOFTIRQ:
@@ -590,7 +690,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
                        list_add_tail(&timer->cb_entry,
                                      &base->cpu_base->cb_pending);
                        timer->state = HRTIMER_STATE_PENDING;
-                       raise_softirq(HRTIMER_SOFTIRQ);
                        return 1;
                default:
                        BUG();
@@ -633,6 +732,11 @@ static int hrtimer_switch_to_hres(void)
        return 1;
 }
 
+static inline void hrtimer_raise_softirq(void)
+{
+       raise_softirq(HRTIMER_SOFTIRQ);
+}
+
 #else
 
 static inline int hrtimer_hres_active(void) { return 0; }
@@ -651,6 +755,7 @@ static inline int hrtimer_reprogram(struct hrtimer *timer,
 {
        return 0;
 }
+static inline void hrtimer_raise_softirq(void) { }
 
 #endif /* CONFIG_HIGH_RES_TIMERS */
 
@@ -689,7 +794,7 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
        u64 orun = 1;
        ktime_t delta;
 
-       delta = ktime_sub(now, timer->expires);
+       delta = ktime_sub(now, hrtimer_get_expires(timer));
 
        if (delta.tv64 < 0)
                return 0;
@@ -701,8 +806,8 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
                s64 incr = ktime_to_ns(interval);
 
                orun = ktime_divns(delta, incr);
-               timer->expires = ktime_add_ns(timer->expires, incr * orun);
-               if (timer->expires.tv64 > now.tv64)
+               hrtimer_add_expires_ns(timer, incr * orun);
+               if (hrtimer_get_expires_tv64(timer) > now.tv64)
                        return orun;
                /*
                 * This (and the ktime_add() below) is the
@@ -710,7 +815,7 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
                 */
                orun++;
        }
-       timer->expires = ktime_add_safe(timer->expires, interval);
+       hrtimer_add_expires(timer, interval);
 
        return orun;
 }
@@ -730,6 +835,8 @@ static void enqueue_hrtimer(struct hrtimer *timer,
        struct hrtimer *entry;
        int leftmost = 1;
 
+       debug_hrtimer_activate(timer);
+
        /*
         * Find the right place in the rbtree:
         */
@@ -740,7 +847,8 @@ static void enqueue_hrtimer(struct hrtimer *timer,
                 * We dont care about collisions. Nodes with
                 * the same expiry time stay together.
                 */
-               if (timer->expires.tv64 < entry->expires.tv64) {
+               if (hrtimer_get_expires_tv64(timer) <
+                               hrtimer_get_expires_tv64(entry)) {
                        link = &(*link)->rb_left;
                } else {
                        link = &(*link)->rb_right;
@@ -826,6 +934,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
                 * reprogramming happens in the interrupt handler. This is a
                 * rare case and less expensive than a smp call.
                 */
+               debug_hrtimer_deactivate(timer);
                timer_stats_hrtimer_clear_start_info(timer);
                reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
                __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE,
@@ -850,7 +959,7 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 {
        struct hrtimer_clock_base *base, *new_base;
        unsigned long flags;
-       int ret;
+       int ret, raise;
 
        base = lock_hrtimer_base(timer, &flags);
 
@@ -873,7 +982,8 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
                tim = ktime_add_safe(tim, base->resolution);
 #endif
        }
-       timer->expires = tim;
+
+       hrtimer_set_expires(timer, tim);
 
        timer_stats_hrtimer_set_start_info(timer);
 
@@ -884,8 +994,26 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
        enqueue_hrtimer(timer, new_base,
                        new_base->cpu_base == &__get_cpu_var(hrtimer_bases));
 
+       /*
+        * The timer may be expired and moved to the cb_pending
+        * list. We can not raise the softirq with base lock held due
+        * to a possible deadlock with runqueue lock.
+        */
+       raise = timer->state == HRTIMER_STATE_PENDING;
+
+       /*
+        * We use preempt_disable to prevent this task from migrating after
+        * setting up the softirq and raising it. Otherwise, if me migrate
+        * we will raise the softirq on the wrong CPU.
+        */
+       preempt_disable();
+
        unlock_hrtimer_base(timer, &flags);
 
+       if (raise)
+               hrtimer_raise_softirq();
+       preempt_enable();
+
        return ret;
 }
 EXPORT_SYMBOL_GPL(hrtimer_start);
@@ -949,14 +1077,14 @@ ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
        ktime_t rem;
 
        base = lock_hrtimer_base(timer, &flags);
-       rem = ktime_sub(timer->expires, base->get_time());
+       rem = hrtimer_expires_remaining(timer);
        unlock_hrtimer_base(timer, &flags);
 
        return rem;
 }
 EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
 
-#if defined(CONFIG_NO_IDLE_HZ) || defined(CONFIG_NO_HZ)
+#ifdef CONFIG_NO_HZ
 /**
  * hrtimer_get_next_event - get the time until next expiry event
  *
@@ -981,7 +1109,7 @@ ktime_t hrtimer_get_next_event(void)
                                continue;
 
                        timer = rb_entry(base->first, struct hrtimer, node);
-                       delta.tv64 = timer->expires.tv64;
+                       delta.tv64 = hrtimer_get_expires_tv64(timer);
                        delta = ktime_sub(delta, base->get_time());
                        if (delta.tv64 < mindelta.tv64)
                                mindelta.tv64 = delta.tv64;
@@ -996,14 +1124,8 @@ ktime_t hrtimer_get_next_event(void)
 }
 #endif
 
-/**
- * hrtimer_init - initialize a timer to the given clock
- * @timer:     the timer to be initialized
- * @clock_id:  the clock to be used
- * @mode:      timer mode abs/rel
- */
-void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
-                 enum hrtimer_mode mode)
+static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+                          enum hrtimer_mode mode)
 {
        struct hrtimer_cpu_base *cpu_base;
 
@@ -1024,6 +1146,19 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
        memset(timer->start_comm, 0, TASK_COMM_LEN);
 #endif
 }
+
+/**
+ * hrtimer_init - initialize a timer to the given clock
+ * @timer:     the timer to be initialized
+ * @clock_id:  the clock to be used
+ * @mode:      timer mode abs/rel
+ */
+void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+                 enum hrtimer_mode mode)
+{
+       debug_hrtimer_init(timer);
+       __hrtimer_init(timer, clock_id, mode);
+}
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
 /**
@@ -1057,6 +1192,7 @@ static void run_hrtimer_pending(struct hrtimer_cpu_base *cpu_base)
                timer = list_entry(cpu_base->cb_pending.next,
                                   struct hrtimer, cb_entry);
 
+               debug_hrtimer_deactivate(timer);
                timer_stats_account_hrtimer(timer);
 
                fn = timer->function;
@@ -1105,6 +1241,7 @@ static void __run_hrtimer(struct hrtimer *timer)
        enum hrtimer_restart (*fn)(struct hrtimer *);
        int restart;
 
+       debug_hrtimer_deactivate(timer);
        __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
        timer_stats_account_hrtimer(timer);
 
@@ -1172,10 +1309,10 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 
                        timer = rb_entry(node, struct hrtimer, node);
 
-                       if (basenow.tv64 < timer->expires.tv64) {
+                       if (basenow.tv64 < hrtimer_get_expires_tv64(timer)) {
                                ktime_t expires;
 
-                               expires = ktime_sub(timer->expires,
+                               expires = ktime_sub(hrtimer_get_expires(timer),
                                                    base->offset);
                                if (expires.tv64 < expires_next.tv64)
                                        expires_next = expires;
@@ -1278,7 +1415,8 @@ void hrtimer_run_queues(void)
                        struct hrtimer *timer;
 
                        timer = rb_entry(node, struct hrtimer, node);
-                       if (base->softirq_time.tv64 <= timer->expires.tv64)
+                       if (base->softirq_time.tv64 <=
+                                       hrtimer_get_expires_tv64(timer))
                                break;
 
                        if (timer->cb_mode == HRTIMER_CB_SOFTIRQ) {
@@ -1326,7 +1464,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 
        do {
                set_current_state(TASK_INTERRUPTIBLE);
-               hrtimer_start(&t->timer, t->timer.expires, mode);
+               hrtimer_start_expires(&t->timer, mode);
                if (!hrtimer_active(&t->timer))
                        t->task = NULL;
 
@@ -1348,7 +1486,7 @@ static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp)
        struct timespec rmt;
        ktime_t rem;
 
-       rem = ktime_sub(timer->expires, timer->base->get_time());
+       rem = hrtimer_expires_remaining(timer);
        if (rem.tv64 <= 0)
                return 0;
        rmt = ktime_to_timespec(rem);
@@ -1363,22 +1501,27 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 {
        struct hrtimer_sleeper t;
        struct timespec __user  *rmtp;
+       int ret = 0;
 
-       hrtimer_init(&t.timer, restart->nanosleep.index, HRTIMER_MODE_ABS);
-       t.timer.expires.tv64 = restart->nanosleep.expires;
+       hrtimer_init_on_stack(&t.timer, restart->nanosleep.index,
+                               HRTIMER_MODE_ABS);
+       hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
 
        if (do_nanosleep(&t, HRTIMER_MODE_ABS))
-               return 0;
+               goto out;
 
        rmtp = restart->nanosleep.rmtp;
        if (rmtp) {
-               int ret = update_rmtp(&t.timer, rmtp);
+               ret = update_rmtp(&t.timer, rmtp);
                if (ret <= 0)
-                       return ret;
+                       goto out;
        }
 
        /* The other values in restart are already filled in */
-       return -ERESTART_RESTARTBLOCK;
+       ret = -ERESTART_RESTARTBLOCK;
+out:
+       destroy_hrtimer_on_stack(&t.timer);
+       return ret;
 }
 
 long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
@@ -1386,29 +1529,35 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 {
        struct restart_block *restart;
        struct hrtimer_sleeper t;
+       int ret = 0;
 
-       hrtimer_init(&t.timer, clockid, mode);
-       t.timer.expires = timespec_to_ktime(*rqtp);
+       hrtimer_init_on_stack(&t.timer, clockid, mode);
+       hrtimer_set_expires(&t.timer, timespec_to_ktime(*rqtp));
        if (do_nanosleep(&t, mode))
-               return 0;
+               goto out;
 
        /* Absolute timers do not update the rmtp value and restart: */
-       if (mode == HRTIMER_MODE_ABS)
-               return -ERESTARTNOHAND;
+       if (mode == HRTIMER_MODE_ABS) {
+               ret = -ERESTARTNOHAND;
+               goto out;
+       }
 
        if (rmtp) {
-               int ret = update_rmtp(&t.timer, rmtp);
+               ret = update_rmtp(&t.timer, rmtp);
                if (ret <= 0)
-                       return ret;
+                       goto out;
        }
 
        restart = &current_thread_info()->restart_block;
        restart->fn = hrtimer_nanosleep_restart;
        restart->nanosleep.index = t.timer.base->index;
        restart->nanosleep.rmtp = rmtp;
-       restart->nanosleep.expires = t.timer.expires.tv64;
+       restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
 
-       return -ERESTART_RESTARTBLOCK;
+       ret = -ERESTART_RESTARTBLOCK;
+out:
+       destroy_hrtimer_on_stack(&t.timer);
+       return ret;
 }
 
 asmlinkage long
@@ -1453,6 +1602,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
        while ((node = rb_first(&old_base->active))) {
                timer = rb_entry(node, struct hrtimer, node);
                BUG_ON(hrtimer_callback_running(timer));
+               debug_hrtimer_deactivate(timer);
                __remove_hrtimer(timer, old_base, HRTIMER_STATE_INACTIVE, 0);
                timer->base = new_base;
                /*
@@ -1526,7 +1676,72 @@ void __init hrtimers_init(void)
                          (void *)(long)smp_processor_id());
        register_cpu_notifier(&hrtimers_nb);
 #ifdef CONFIG_HIGH_RES_TIMERS
-       open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq, NULL);
+       open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq);
 #endif
 }
 
+/**
+ * schedule_hrtimeout - sleep until timeout
+ * @expires:   timeout value (ktime_t)
+ * @mode:      timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
+ *
+ * Make the current task sleep until the given expiry time has
+ * elapsed. The routine will return immediately unless
+ * the current task state has been set (see set_current_state()).
+ *
+ * You can set the task state as follows -
+ *
+ * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
+ * pass before the routine returns.
+ *
+ * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
+ * delivered to the current task.
+ *
+ * The current task state is guaranteed to be TASK_RUNNING when this
+ * routine returns.
+ *
+ * Returns 0 when the timer has expired otherwise -EINTR
+ */
+int __sched schedule_hrtimeout(ktime_t *expires,
+                              const enum hrtimer_mode mode)
+{
+       struct hrtimer_sleeper t;
+
+       /*
+        * Optimize when a zero timeout value is given. It does not
+        * matter whether this is an absolute or a relative time.
+        */
+       if (expires && !expires->tv64) {
+               __set_current_state(TASK_RUNNING);
+               return 0;
+       }
+
+       /*
+        * A NULL parameter means "inifinte"
+        */
+       if (!expires) {
+               schedule();
+               __set_current_state(TASK_RUNNING);
+               return -EINTR;
+       }
+
+       hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, mode);
+       hrtimer_set_expires(&t.timer, *expires);
+
+       hrtimer_init_sleeper(&t, current);
+
+       hrtimer_start_expires(&t.timer, mode);
+       if (!hrtimer_active(&t.timer))
+               t.task = NULL;
+
+       if (likely(t.task))
+               schedule();
+
+       hrtimer_cancel(&t.timer);
+       destroy_hrtimer_on_stack(&t.timer);
+
+       __set_current_state(TASK_RUNNING);
+
+       return !t.task ? 0 : -EINTR;
+}
+EXPORT_SYMBOL_GPL(schedule_hrtimeout);