hrtimer: Use cpu_base->active_base for hotpath iterators
[firefly-linux-kernel-4.4.55.git] / kernel / time / hrtimer.c
index 874e0914eb3c0bbe95ce3aafc4cfddbfffff9227..fce0ccf97b51e60a57fc5fbcca6fb09e37a77734 100644 (file)
@@ -104,27 +104,6 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id)
        return hrtimer_clock_to_base_table[clock_id];
 }
 
-
-/*
- * Get the coarse grained time at the softirq based on xtime and
- * wall_to_monotonic.
- */
-static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
-{
-       ktime_t xtim, mono, boot, tai;
-       ktime_t off_real, off_boot, off_tai;
-
-       mono = ktime_get_update_offsets_tick(&off_real, &off_boot, &off_tai);
-       boot = ktime_add(mono, off_boot);
-       xtim = ktime_add(mono, off_real);
-       tai = ktime_add(mono, off_tai);
-
-       base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim;
-       base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono;
-       base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot;
-       base->clock_base[HRTIMER_BASE_TAI].softirq_time = tai;
-}
-
 /*
  * Functions and macros which are different for UP/SMP systems are kept in a
  * single place
@@ -440,16 +419,16 @@ static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base)
 {
        struct hrtimer_clock_base *base = cpu_base->clock_base;
        ktime_t expires, expires_next = { .tv64 = KTIME_MAX };
-       int i;
+       unsigned int active = cpu_base->active_bases;
 
-       for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
+       for (; active; base++, active >>= 1) {
                struct timerqueue_node *next;
                struct hrtimer *timer;
 
-               next = timerqueue_getnext(&base->active);
-               if (!next)
+               if (!(active & 0x01))
                        continue;
 
+               next = timerqueue_getnext(&base->active);
                timer = container_of(next, struct hrtimer, node);
                expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
                if (expires.tv64 < expires_next.tv64)
@@ -466,6 +445,16 @@ static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base)
 }
 #endif
 
+static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
+{
+       ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
+       ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
+       ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
+
+       return ktime_get_update_offsets_now(&base->clock_was_set_seq,
+                                           offs_real, offs_boot, offs_tai);
+}
+
 /* High resolution timer related functions */
 #ifdef CONFIG_HIGH_RES_TIMERS
 
@@ -503,9 +492,14 @@ static inline int hrtimer_is_hres_enabled(void)
 /*
  * Is the high resolution mode active ?
  */
+static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base)
+{
+       return cpu_base->hres_active;
+}
+
 static inline int hrtimer_hres_active(void)
 {
-       return __this_cpu_read(hrtimer_bases.hres_active);
+       return __hrtimer_hres_active(this_cpu_ptr(&hrtimer_bases));
 }
 
 /*
@@ -516,7 +510,12 @@ static inline int hrtimer_hres_active(void)
 static void
 hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
 {
-       ktime_t expires_next = __hrtimer_get_next_event(cpu_base);
+       ktime_t expires_next;
+
+       if (!cpu_base->hres_active)
+               return;
+
+       expires_next = __hrtimer_get_next_event(cpu_base);
 
        if (skip_equal && expires_next.tv64 == cpu_base->expires_next.tv64)
                return;
@@ -625,15 +624,6 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
        base->hres_active = 0;
 }
 
-static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
-{
-       ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
-       ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
-       ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
-
-       return ktime_get_update_offsets_now(offs_real, offs_boot, offs_tai);
-}
-
 /*
  * Retrigger next event is called after clock was set
  *
@@ -643,7 +633,7 @@ static void retrigger_next_event(void *arg)
 {
        struct hrtimer_cpu_base *base = this_cpu_ptr(&hrtimer_bases);
 
-       if (!hrtimer_hres_active())
+       if (!base->hres_active)
                return;
 
        raw_spin_lock(&base->lock);
@@ -700,6 +690,7 @@ void clock_was_set_delayed(void)
 
 #else
 
+static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *b) { return 0; }
 static inline int hrtimer_hres_active(void) { return 0; }
 static inline int hrtimer_is_hres_enabled(void) { return 0; }
 static inline int hrtimer_switch_to_hres(void) { return 0; }
@@ -877,25 +868,27 @@ static void __remove_hrtimer(struct hrtimer *timer,
                             struct hrtimer_clock_base *base,
                             unsigned long newstate, int reprogram)
 {
+       struct hrtimer_cpu_base *cpu_base = base->cpu_base;
        struct timerqueue_node *next_timer;
+
        if (!(timer->state & HRTIMER_STATE_ENQUEUED))
                goto out;
 
        next_timer = timerqueue_getnext(&base->active);
        timerqueue_del(&base->active, &timer->node);
        if (!timerqueue_getnext(&base->active))
-               base->cpu_base->active_bases &= ~(1 << base->index);
+               cpu_base->active_bases &= ~(1 << base->index);
 
        if (&timer->node == next_timer) {
 #ifdef CONFIG_HIGH_RES_TIMERS
                /* Reprogram the clock event device. if enabled */
-               if (reprogram && hrtimer_hres_active()) {
+               if (reprogram && cpu_base->hres_active) {
                        ktime_t expires;
 
                        expires = ktime_sub(hrtimer_get_expires(timer),
                                            base->offset);
-                       if (base->cpu_base->expires_next.tv64 == expires.tv64)
-                               hrtimer_force_reprogram(base->cpu_base, 1);
+                       if (cpu_base->expires_next.tv64 == expires.tv64)
+                               hrtimer_force_reprogram(cpu_base, 1);
                }
 #endif
        }
@@ -1129,7 +1122,7 @@ ktime_t hrtimer_get_next_event(void)
 
        raw_spin_lock_irqsave(&cpu_base->lock, flags);
 
-       if (!hrtimer_hres_active())
+       if (!__hrtimer_hres_active(cpu_base))
                mindelta = ktime_sub(__hrtimer_get_next_event(cpu_base),
                                     ktime_get());
 
@@ -1179,10 +1172,10 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
-static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
+static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
+                         struct hrtimer_clock_base *base,
+                         struct hrtimer *timer, ktime_t *now)
 {
-       struct hrtimer_clock_base *base = timer->base;
-       struct hrtimer_cpu_base *cpu_base = base->cpu_base;
        enum hrtimer_restart (*fn)(struct hrtimer *);
        int restart;
 
@@ -1219,44 +1212,18 @@ static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
        timer->state &= ~HRTIMER_STATE_CALLBACK;
 }
 
-#ifdef CONFIG_HIGH_RES_TIMERS
-
-/*
- * High resolution timer interrupt
- * Called with interrupts disabled
- */
-void hrtimer_interrupt(struct clock_event_device *dev)
+static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
 {
-       struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
-       ktime_t expires_next, now, entry_time, delta;
-       int i, retries = 0;
-
-       BUG_ON(!cpu_base->hres_active);
-       cpu_base->nr_events++;
-       dev->next_event.tv64 = KTIME_MAX;
-
-       raw_spin_lock(&cpu_base->lock);
-       entry_time = now = hrtimer_update_base(cpu_base);
-retry:
-       cpu_base->in_hrtirq = 1;
-       /*
-        * We set expires_next to KTIME_MAX here with cpu_base->lock
-        * held to prevent that a timer is enqueued in our queue via
-        * the migration code. This does not affect enqueueing of
-        * timers which run their callback and need to be requeued on
-        * this CPU.
-        */
-       cpu_base->expires_next.tv64 = KTIME_MAX;
+       struct hrtimer_clock_base *base = cpu_base->clock_base;
+       unsigned int active = cpu_base->active_bases;
 
-       for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
-               struct hrtimer_clock_base *base;
+       for (; active; base++, active >>= 1) {
                struct timerqueue_node *node;
                ktime_t basenow;
 
-               if (!(cpu_base->active_bases & (1 << i)))
+               if (!(active & 0x01))
                        continue;
 
-               base = cpu_base->clock_base + i;
                basenow = ktime_add(now, base->offset);
 
                while ((node = timerqueue_getnext(&base->active))) {
@@ -1279,9 +1246,42 @@ retry:
                        if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer))
                                break;
 
-                       __run_hrtimer(timer, &basenow);
+                       __run_hrtimer(cpu_base, base, timer, &basenow);
                }
        }
+}
+
+#ifdef CONFIG_HIGH_RES_TIMERS
+
+/*
+ * High resolution timer interrupt
+ * Called with interrupts disabled
+ */
+void hrtimer_interrupt(struct clock_event_device *dev)
+{
+       struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
+       ktime_t expires_next, now, entry_time, delta;
+       int retries = 0;
+
+       BUG_ON(!cpu_base->hres_active);
+       cpu_base->nr_events++;
+       dev->next_event.tv64 = KTIME_MAX;
+
+       raw_spin_lock(&cpu_base->lock);
+       entry_time = now = hrtimer_update_base(cpu_base);
+retry:
+       cpu_base->in_hrtirq = 1;
+       /*
+        * We set expires_next to KTIME_MAX here with cpu_base->lock
+        * held to prevent that a timer is enqueued in our queue via
+        * the migration code. This does not affect enqueueing of
+        * timers which run their callback and need to be requeued on
+        * this CPU.
+        */
+       cpu_base->expires_next.tv64 = KTIME_MAX;
+
+       __hrtimer_run_queues(cpu_base, now);
+
        /* Reevaluate the clock bases for the next expiry */
        expires_next = __hrtimer_get_next_event(cpu_base);
        /*
@@ -1416,38 +1416,16 @@ void hrtimer_run_pending(void)
  */
 void hrtimer_run_queues(void)
 {
-       struct timerqueue_node *node;
        struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
-       struct hrtimer_clock_base *base;
-       int index, gettime = 1;
+       ktime_t now;
 
-       if (hrtimer_hres_active())
+       if (__hrtimer_hres_active(cpu_base))
                return;
 
-       for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
-               base = &cpu_base->clock_base[index];
-               if (!timerqueue_getnext(&base->active))
-                       continue;
-
-               if (gettime) {
-                       hrtimer_get_softirq_time(cpu_base);
-                       gettime = 0;
-               }
-
-               raw_spin_lock(&cpu_base->lock);
-
-               while ((node = timerqueue_getnext(&base->active))) {
-                       struct hrtimer *timer;
-
-                       timer = container_of(node, struct hrtimer, node);
-                       if (base->softirq_time.tv64 <=
-                                       hrtimer_get_expires_tv64(timer))
-                               break;
-
-                       __run_hrtimer(timer, &base->softirq_time);
-               }
-               raw_spin_unlock(&cpu_base->lock);
-       }
+       raw_spin_lock(&cpu_base->lock);
+       now = hrtimer_update_base(cpu_base);
+       __hrtimer_run_queues(cpu_base, now);
+       raw_spin_unlock(&cpu_base->lock);
 }
 
 /*