---

yaml --- r: 150972 b: refs/heads/master c: cd6d95d h: refs/heads/master v: v3
git-mirror · Jun 13, 2009 · 9c027b5 · 9c027b5
1 parent a902c5f
commit 9c027b5
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Showing 6 changed files with 34 additions and 12 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3f68535adad8dd89499505a65fb25d0e02d118cc
+refs/heads/master: cd6d95d8449b7c9f415f26041e9ae173d387b6bd
diff --git a/trunk/include/linux/hrtimer.h b/trunk/include/linux/hrtimer.h
@@ -305,7 +305,7 @@ static inline int hrtimer_is_hres_active(struct hrtimer *timer)
 
 extern ktime_t ktime_get(void);
 extern ktime_t ktime_get_real(void);
-extern int hrtimer_hres_active(void);
+
 
 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
 

diff --git a/trunk/include/linux/tick.h b/trunk/include/linux/tick.h
@@ -97,10 +97,12 @@ extern void tick_clock_notify(void);
 extern int tick_check_oneshot_change(int allow_nohz);
 extern struct tick_sched *tick_get_tick_sched(int cpu);
 extern void tick_check_idle(int cpu);
+extern int tick_oneshot_mode_active(void);
 # else
 static inline void tick_clock_notify(void) { }
 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
 static inline void tick_check_idle(int cpu) { }
+static inline int tick_oneshot_mode_active(void) { return 0; }
 # endif
 
 #else /* CONFIG_GENERIC_CLOCKEVENTS */
@@ -109,6 +111,7 @@ static inline void tick_cancel_sched_timer(int cpu) { }
 static inline void tick_clock_notify(void) { }
 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
 static inline void tick_check_idle(int cpu) { }
+static inline int tick_oneshot_mode_active(void) { return 0; }
 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
 
 # ifdef CONFIG_NO_HZ

diff --git a/trunk/kernel/hrtimer.c b/trunk/kernel/hrtimer.c
@@ -476,7 +476,7 @@ static inline int hrtimer_is_hres_enabled(void)
 /*
  * Is the high resolution mode active ?
  */
-int hrtimer_hres_active(void)
+static inline int hrtimer_hres_active(void)
 {
 	return __get_cpu_var(hrtimer_bases).hres_active;
 }
@@ -704,7 +704,7 @@ static int hrtimer_switch_to_hres(void)
 
 #else
 
-int hrtimer_hres_active(void) { 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; }
 static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base) { }

diff --git a/trunk/kernel/time/clocksource.c b/trunk/kernel/time/clocksource.c
@@ -30,7 +30,6 @@
 #include <linux/module.h>
 #include <linux/sched.h> /* for spin_unlock_irq() using preempt_count() m68k */
 #include <linux/tick.h>
-#include <linux/hrtimer.h>
 
 void timecounter_init(struct timecounter *tc,
 		      const struct cyclecounter *cc,
@@ -511,13 +510,13 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev,
 	}
 
 	/*
-	 * Check to make sure we don't switch to a non-HRT usable
-	 * clocksource if HRT is enabled and running
+	 * Check to make sure we don't switch to a non-highres capable
+	 * clocksource if the tick code is in oneshot mode (highres or nohz)
 	 */
-	if (hrtimer_hres_active() &&
+	if (tick_oneshot_mode_active() &&
 	    !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) {
 		printk(KERN_WARNING "%s clocksource is not HRT compatible. "
-			"Cannot switch while in HRT mode\n", ovr->name);
+			"Cannot switch while in HRT/NOHZ mode\n", ovr->name);
 		ovr = NULL;
 		override_name[0] = 0;
 	}
@@ -550,9 +549,12 @@ sysfs_show_available_clocksources(struct sys_device *dev,
 
 	spin_lock_irq(&clocksource_lock);
 	list_for_each_entry(src, &clocksource_list, list) {
-		/* Don't show non-HRES clocksource if HRES is enabled */
-		if (!hrtimer_hres_active() ||
-				(src->flags & CLOCK_SOURCE_VALID_FOR_HRES))
+		/*
+		 * Don't show non-HRES clocksource if the tick code is
+		 * in one shot mode (highres=on or nohz=on)
+		 */
+		if (!tick_oneshot_mode_active() ||
+		    (src->flags & CLOCK_SOURCE_VALID_FOR_HRES))
 			count += snprintf(buf + count,
 				  max((ssize_t)PAGE_SIZE - count, (ssize_t)0),
 				  "%s ", src->name);

diff --git a/trunk/kernel/time/tick-oneshot.c b/trunk/kernel/time/tick-oneshot.c
@@ -128,6 +128,23 @@ int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *))
 	return 0;
 }
 
+/**
+ * tick_check_oneshot_mode - check whether the system is in oneshot mode
+ *
+ * returns 1 when either nohz or highres are enabled. otherwise 0.
+ */
+int tick_oneshot_mode_active(void)
+{
+	unsigned long flags;
+	int ret;
+
+	local_irq_save(flags);
+	ret = __get_cpu_var(tick_cpu_device).mode == TICKDEV_MODE_ONESHOT;
+	local_irq_restore(flags);
+
+	return ret;
+}
+
 #ifdef CONFIG_HIGH_RES_TIMERS
 /**
  * tick_init_highres - switch to high resolution mode