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authorMark Brown <broonie@linaro.org>2013-12-08 21:51:13 +0000
committerMark Brown <broonie@linaro.org>2013-12-08 21:51:13 +0000
commit925b33756551cb5304774d2e2b39e26e82308a68 (patch)
tree92c8b41c6dec82d205a7407916e5461a1d1c8c19 /kernel
parentdffe2a3eed105c631500778dfaba0998d7bf8512 (diff)
parent184c20bbc978eb7a2e1d3637b7864208822c7ebc (diff)
downloadlinaro-lsk-925b33756551cb5304774d2e2b39e26e82308a68.tar.gz
Merge tag 'v3.10.23' into linux-linaro-lsk
This is the 3.10.23 stable release
Diffstat (limited to 'kernel')
-rw-r--r--kernel/time/clockevents.c36
-rw-r--r--kernel/time/ntp.c3
-rw-r--r--kernel/time/tick-broadcast.c33
-rw-r--r--kernel/time/tick-common.c106
-rw-r--r--kernel/time/tick-internal.h7
5 files changed, 84 insertions, 101 deletions
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 6a23c6c556c..9df0e3b19f0 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -15,7 +15,6 @@
#include <linux/hrtimer.h>
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/notifier.h>
#include <linux/smp.h>
#include "tick-internal.h"
@@ -23,10 +22,6 @@
/* The registered clock event devices */
static LIST_HEAD(clockevent_devices);
static LIST_HEAD(clockevents_released);
-
-/* Notification for clock events */
-static RAW_NOTIFIER_HEAD(clockevents_chain);
-
/* Protection for the above */
static DEFINE_RAW_SPINLOCK(clockevents_lock);
@@ -267,30 +262,6 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires,
return (rc && force) ? clockevents_program_min_delta(dev) : rc;
}
-/**
- * clockevents_register_notifier - register a clock events change listener
- */
-int clockevents_register_notifier(struct notifier_block *nb)
-{
- unsigned long flags;
- int ret;
-
- raw_spin_lock_irqsave(&clockevents_lock, flags);
- ret = raw_notifier_chain_register(&clockevents_chain, nb);
- raw_spin_unlock_irqrestore(&clockevents_lock, flags);
-
- return ret;
-}
-
-/*
- * Notify about a clock event change. Called with clockevents_lock
- * held.
- */
-static void clockevents_do_notify(unsigned long reason, void *dev)
-{
- raw_notifier_call_chain(&clockevents_chain, reason, dev);
-}
-
/*
* Called after a notify add to make devices available which were
* released from the notifier call.
@@ -304,7 +275,7 @@ static void clockevents_notify_released(void)
struct clock_event_device, list);
list_del(&dev->list);
list_add(&dev->list, &clockevent_devices);
- clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev);
+ tick_check_new_device(dev);
}
}
@@ -325,7 +296,7 @@ void clockevents_register_device(struct clock_event_device *dev)
raw_spin_lock_irqsave(&clockevents_lock, flags);
list_add(&dev->list, &clockevent_devices);
- clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev);
+ tick_check_new_device(dev);
clockevents_notify_released();
raw_spin_unlock_irqrestore(&clockevents_lock, flags);
@@ -421,6 +392,7 @@ void clockevents_exchange_device(struct clock_event_device *old,
* released list and do a notify add later.
*/
if (old) {
+ module_put(old->owner);
clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED);
list_del(&old->list);
list_add(&old->list, &clockevents_released);
@@ -468,7 +440,7 @@ void clockevents_notify(unsigned long reason, void *arg)
int cpu;
raw_spin_lock_irqsave(&clockevents_lock, flags);
- clockevents_do_notify(reason, arg);
+ tick_notify(reason, arg);
switch (reason) {
case CLOCK_EVT_NOTIFY_CPU_DEAD:
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index bb2215174f0..af8d1d4f3d5 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -475,6 +475,7 @@ static void sync_cmos_clock(struct work_struct *work)
* called as close as possible to 500 ms before the new second starts.
* This code is run on a timer. If the clock is set, that timer
* may not expire at the correct time. Thus, we adjust...
+ * We want the clock to be within a couple of ticks from the target.
*/
if (!ntp_synced()) {
/*
@@ -485,7 +486,7 @@ static void sync_cmos_clock(struct work_struct *work)
}
getnstimeofday(&now);
- if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) {
+ if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec * 5) {
struct timespec adjust = now;
fail = -ENODEV;
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 297b90b5277..52d4827cf2d 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -19,6 +19,7 @@
#include <linux/profile.h>
#include <linux/sched.h>
#include <linux/smp.h>
+#include <linux/module.h>
#include "tick-internal.h"
@@ -65,17 +66,34 @@ static void tick_broadcast_start_periodic(struct clock_event_device *bc)
/*
* Check, if the device can be utilized as broadcast device:
*/
-int tick_check_broadcast_device(struct clock_event_device *dev)
+static bool tick_check_broadcast_device(struct clock_event_device *curdev,
+ struct clock_event_device *newdev)
+{
+ if ((newdev->features & CLOCK_EVT_FEAT_DUMMY) ||
+ (newdev->features & CLOCK_EVT_FEAT_C3STOP))
+ return false;
+
+ if (tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT &&
+ !(newdev->features & CLOCK_EVT_FEAT_ONESHOT))
+ return false;
+
+ return !curdev || newdev->rating > curdev->rating;
+}
+
+/*
+ * Conditionally install/replace broadcast device
+ */
+void tick_install_broadcast_device(struct clock_event_device *dev)
{
struct clock_event_device *cur = tick_broadcast_device.evtdev;
- if ((dev->features & CLOCK_EVT_FEAT_DUMMY) ||
- (tick_broadcast_device.evtdev &&
- tick_broadcast_device.evtdev->rating >= dev->rating) ||
- (dev->features & CLOCK_EVT_FEAT_C3STOP))
- return 0;
+ if (!tick_check_broadcast_device(cur, dev))
+ return;
+
+ if (!try_module_get(dev->owner))
+ return;
- clockevents_exchange_device(tick_broadcast_device.evtdev, dev);
+ clockevents_exchange_device(cur, dev);
if (cur)
cur->event_handler = clockevents_handle_noop;
tick_broadcast_device.evtdev = dev;
@@ -91,7 +109,6 @@ int tick_check_broadcast_device(struct clock_event_device *dev)
*/
if (dev->features & CLOCK_EVT_FEAT_ONESHOT)
tick_clock_notify();
- return 1;
}
/*
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 7ce5e5a4a4c..086216c433f 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -18,6 +18,7 @@
#include <linux/percpu.h>
#include <linux/profile.h>
#include <linux/sched.h>
+#include <linux/module.h>
#include <asm/irq_regs.h>
@@ -206,14 +207,50 @@ static void tick_setup_device(struct tick_device *td,
tick_setup_oneshot(newdev, handler, next_event);
}
+static bool tick_check_percpu(struct clock_event_device *curdev,
+ struct clock_event_device *newdev, int cpu)
+{
+ if (!cpumask_test_cpu(cpu, newdev->cpumask))
+ return false;
+ if (cpumask_equal(newdev->cpumask, cpumask_of(cpu)))
+ return true;
+ /* Check if irq affinity can be set */
+ if (newdev->irq >= 0 && !irq_can_set_affinity(newdev->irq))
+ return false;
+ /* Prefer an existing cpu local device */
+ if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu)))
+ return false;
+ return true;
+}
+
+static bool tick_check_preferred(struct clock_event_device *curdev,
+ struct clock_event_device *newdev)
+{
+ /* Prefer oneshot capable device */
+ if (!(newdev->features & CLOCK_EVT_FEAT_ONESHOT)) {
+ if (curdev && (curdev->features & CLOCK_EVT_FEAT_ONESHOT))
+ return false;
+ if (tick_oneshot_mode_active())
+ return false;
+ }
+
+ /*
+ * Use the higher rated one, but prefer a CPU local device with a lower
+ * rating than a non-CPU local device
+ */
+ return !curdev ||
+ newdev->rating > curdev->rating ||
+ !cpumask_equal(curdev->cpumask, newdev->cpumask);
+}
+
/*
* Check, if the new registered device should be used.
*/
-static int tick_check_new_device(struct clock_event_device *newdev)
+void tick_check_new_device(struct clock_event_device *newdev)
{
struct clock_event_device *curdev;
struct tick_device *td;
- int cpu, ret = NOTIFY_OK;
+ int cpu;
unsigned long flags;
raw_spin_lock_irqsave(&tick_device_lock, flags);
@@ -226,40 +263,15 @@ static int tick_check_new_device(struct clock_event_device *newdev)
curdev = td->evtdev;
/* cpu local device ? */
- if (!cpumask_equal(newdev->cpumask, cpumask_of(cpu))) {
-
- /*
- * If the cpu affinity of the device interrupt can not
- * be set, ignore it.
- */
- if (!irq_can_set_affinity(newdev->irq))
- goto out_bc;
+ if (!tick_check_percpu(curdev, newdev, cpu))
+ goto out_bc;
- /*
- * If we have a cpu local device already, do not replace it
- * by a non cpu local device
- */
- if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu)))
- goto out_bc;
- }
+ /* Preference decision */
+ if (!tick_check_preferred(curdev, newdev))
+ goto out_bc;
- /*
- * If we have an active device, then check the rating and the oneshot
- * feature.
- */
- if (curdev) {
- /*
- * Prefer one shot capable devices !
- */
- if ((curdev->features & CLOCK_EVT_FEAT_ONESHOT) &&
- !(newdev->features & CLOCK_EVT_FEAT_ONESHOT))
- goto out_bc;
- /*
- * Check the rating
- */
- if (curdev->rating >= newdev->rating)
- goto out_bc;
- }
+ if (!try_module_get(newdev->owner))
+ return;
/*
* Replace the eventually existing device by the new
@@ -276,18 +288,14 @@ static int tick_check_new_device(struct clock_event_device *newdev)
tick_oneshot_notify();
raw_spin_unlock_irqrestore(&tick_device_lock, flags);
- return NOTIFY_STOP;
+ return;
out_bc:
/*
* Can the new device be used as a broadcast device ?
*/
- if (tick_check_broadcast_device(newdev))
- ret = NOTIFY_STOP;
-
+ tick_install_broadcast_device(newdev);
raw_spin_unlock_irqrestore(&tick_device_lock, flags);
-
- return ret;
}
/*
@@ -361,17 +369,10 @@ static void tick_resume(void)
raw_spin_unlock_irqrestore(&tick_device_lock, flags);
}
-/*
- * Notification about clock event devices
- */
-static int tick_notify(struct notifier_block *nb, unsigned long reason,
- void *dev)
+void tick_notify(unsigned long reason, void *dev)
{
switch (reason) {
- case CLOCK_EVT_NOTIFY_ADD:
- return tick_check_new_device(dev);
-
case CLOCK_EVT_NOTIFY_BROADCAST_ON:
case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
@@ -405,21 +406,12 @@ static int tick_notify(struct notifier_block *nb, unsigned long reason,
default:
break;
}
-
- return NOTIFY_OK;
}
-static struct notifier_block tick_notifier = {
- .notifier_call = tick_notify,
-};
-
/**
* tick_init - initialize the tick control
- *
- * Register the notifier with the clockevents framework
*/
void __init tick_init(void)
{
- clockevents_register_notifier(&tick_notifier);
tick_broadcast_init();
}
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index f0299eae460..60742fe6f63 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -18,6 +18,8 @@ extern int tick_do_timer_cpu __read_mostly;
extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
extern void tick_handle_periodic(struct clock_event_device *dev);
+extern void tick_notify(unsigned long reason, void *dev);
+extern void tick_check_new_device(struct clock_event_device *dev);
extern void clockevents_shutdown(struct clock_event_device *dev);
@@ -90,7 +92,7 @@ static inline bool tick_broadcast_oneshot_available(void) { return false; }
*/
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
-extern int tick_check_broadcast_device(struct clock_event_device *dev);
+extern void tick_install_broadcast_device(struct clock_event_device *dev);
extern int tick_is_broadcast_device(struct clock_event_device *dev);
extern void tick_broadcast_on_off(unsigned long reason, int *oncpu);
extern void tick_shutdown_broadcast(unsigned int *cpup);
@@ -102,9 +104,8 @@ tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
#else /* !BROADCAST */
-static inline int tick_check_broadcast_device(struct clock_event_device *dev)
+static inline void tick_install_broadcast_device(struct clock_event_device *dev)
{
- return 0;
}
static inline int tick_is_broadcast_device(struct clock_event_device *dev)