X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fhrtimer.c;h=f994bb8065e6bc6b5ea48f437bae62c97af1db20;hb=0d1311a536a0face6267e7346223f2e68b002018;hp=c21ca6bfaa6600dd864ef1b32798dc1a4ae8c081;hpb=e4903fb59590f86190280a549420f6cb85bd7f7e;p=linux-2.6-omap-h63xx.git

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c21ca6bfaa6..f994bb8065e 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -277,6 +277,30 @@ ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
 }
 
 EXPORT_SYMBOL_GPL(ktime_add_ns);
+
+/**
+ * ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable
+ * @kt:		minuend
+ * @nsec:	the scalar nsec value to subtract
+ *
+ * Returns the subtraction of @nsec from @kt in ktime_t format
+ */
+ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec)
+{
+	ktime_t tmp;
+
+	if (likely(nsec < NSEC_PER_SEC)) {
+		tmp.tv64 = nsec;
+	} else {
+		unsigned long rem = do_div(nsec, NSEC_PER_SEC);
+
+		tmp = ktime_set((long)nsec, rem);
+	}
+
+	return ktime_sub(kt, tmp);
+}
+
+EXPORT_SYMBOL_GPL(ktime_sub_ns);
 # endif /* !CONFIG_KTIME_SCALAR */
 
 /*
@@ -388,7 +412,7 @@ static int hrtimer_reprogram(struct hrtimer *timer,
 	/*
 	 * When the callback is running, we do not reprogram the clock event
 	 * device. The timer callback is either running on a different CPU or
-	 * the callback is executed in the hrtimer_interupt context. The
+	 * the callback is executed in the hrtimer_interrupt context. The
 	 * reprogramming is handled either by the softirq, which called the
 	 * callback or at the end of the hrtimer_interrupt.
 	 */
@@ -578,7 +602,7 @@ static int hrtimer_switch_to_hres(void)
 	/* "Retrigger" the interrupt to get things going */
 	retrigger_next_event(NULL);
 	local_irq_restore(flags);
-	printk(KERN_INFO "Switched to high resolution mode on CPU %d\n",
+	printk(KERN_DEBUG "Switched to high resolution mode on CPU %d\n",
 	       smp_processor_id());
 	return 1;
 }
@@ -614,7 +638,7 @@ void __timer_stats_hrtimer_set_start_info(struct hrtimer *timer, void *addr)
 #endif
 
 /*
- * Counterpart to lock_timer_base above:
+ * Counterpart to lock_hrtimer_base above:
  */
 static inline
 void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
@@ -826,6 +850,14 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 #ifdef CONFIG_TIME_LOW_RES
 		tim = ktime_add(tim, base->resolution);
 #endif
+		/*
+		 * Careful here: User space might have asked for a
+		 * very long sleep, so the add above might result in a
+		 * negative number, which enqueues the timer in front
+		 * of the queue.
+		 */
+		if (tim.tv64 < 0)
+			tim.tv64 = KTIME_MAX;
 	}
 	timer->expires = tim;
 
@@ -1262,8 +1294,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 {
 	struct hrtimer_sleeper t;
-	struct timespec __user *rmtp;
-	struct timespec tu;
+	struct timespec *rmtp;
 	ktime_t time;
 
 	restart->fn = do_no_restart_syscall;
@@ -1274,14 +1305,12 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 	if (do_nanosleep(&t, HRTIMER_MODE_ABS))
 		return 0;
 
-	rmtp = (struct timespec __user *) restart->arg1;
+	rmtp = (struct timespec *)restart->arg1;
 	if (rmtp) {
 		time = ktime_sub(t.timer.expires, t.timer.base->get_time());
 		if (time.tv64 <= 0)
 			return 0;
-		tu = ktime_to_timespec(time);
-		if (copy_to_user(rmtp, &tu, sizeof(tu)))
-			return -EFAULT;
+		*rmtp = ktime_to_timespec(time);
 	}
 
 	restart->fn = hrtimer_nanosleep_restart;
@@ -1290,12 +1319,11 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 	return -ERESTART_RESTARTBLOCK;
 }
 
-long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+long hrtimer_nanosleep(struct timespec *rqtp, struct timespec *rmtp,
 		       const enum hrtimer_mode mode, const clockid_t clockid)
 {
 	struct restart_block *restart;
 	struct hrtimer_sleeper t;
-	struct timespec tu;
 	ktime_t rem;
 
 	hrtimer_init(&t.timer, clockid, mode);
@@ -1311,9 +1339,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 		rem = ktime_sub(t.timer.expires, t.timer.base->get_time());
 		if (rem.tv64 <= 0)
 			return 0;
-		tu = ktime_to_timespec(rem);
-		if (copy_to_user(rmtp, &tu, sizeof(tu)))
-			return -EFAULT;
+		*rmtp = ktime_to_timespec(rem);
 	}
 
 	restart = &current_thread_info()->restart_block;
@@ -1329,7 +1355,8 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 asmlinkage long
 sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
 {
-	struct timespec tu;
+	struct timespec tu, rmt;
+	int ret;
 
 	if (copy_from_user(&tu, rqtp, sizeof(tu)))
 		return -EFAULT;
@@ -1337,13 +1364,21 @@ sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
 	if (!timespec_valid(&tu))
 		return -EINVAL;
 
-	return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+	ret = hrtimer_nanosleep(&tu, rmtp ? &rmt : NULL, HRTIMER_MODE_REL,
+				CLOCK_MONOTONIC);
+
+	if (ret && rmtp) {
+		if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
+			return -EFAULT;
+	}
+
+	return ret;
 }
 
 /*
  * Functions related to boot-time initialization:
  */
-static void __devinit init_hrtimers_cpu(int cpu)
+static void __cpuinit init_hrtimers_cpu(int cpu)
 {
 	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
 	int i;