[PATCH 73/74] kernel: broadcast-hrtimer: Migrate to new 'set-state' interface

From: Daniel Lezcano
Date: Mon Aug 10 2015 - 05:57:30 EST


From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

Migrate broadcast-hrtimer driver to the new 'set-state' interface
provided by clockevents core, the earlier 'set-mode' interface is marked
obsolete now.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
kernel/time/tick-broadcast-hrtimer.c | 49 +++++++++++++++---------------------
1 file changed, 20 insertions(+), 29 deletions(-)

diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
index 3e7db49..53d7184 100644
--- a/kernel/time/tick-broadcast-hrtimer.c
+++ b/kernel/time/tick-broadcast-hrtimer.c
@@ -18,30 +18,23 @@

static struct hrtimer bctimer;

-static void bc_set_mode(enum clock_event_mode mode,
- struct clock_event_device *bc)
+static int bc_shutdown(struct clock_event_device *evt)
{
- switch (mode) {
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- /*
- * Note, we cannot cancel the timer here as we might
- * run into the following live lock scenario:
- *
- * cpu 0 cpu1
- * lock(broadcast_lock);
- * hrtimer_interrupt()
- * bc_handler()
- * tick_handle_oneshot_broadcast();
- * lock(broadcast_lock);
- * hrtimer_cancel()
- * wait_for_callback()
- */
- hrtimer_try_to_cancel(&bctimer);
- break;
- default:
- break;
- }
+ /*
+ * Note, we cannot cancel the timer here as we might
+ * run into the following live lock scenario:
+ *
+ * cpu 0 cpu1
+ * lock(broadcast_lock);
+ * hrtimer_interrupt()
+ * bc_handler()
+ * tick_handle_oneshot_broadcast();
+ * lock(broadcast_lock);
+ * hrtimer_cancel()
+ * wait_for_callback()
+ */
+ hrtimer_try_to_cancel(&bctimer);
+ return 0;
}

/*
@@ -82,7 +75,7 @@ static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
}

static struct clock_event_device ce_broadcast_hrtimer = {
- .set_mode = bc_set_mode,
+ .set_state_shutdown = bc_shutdown,
.set_next_ktime = bc_set_next,
.features = CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_KTIME |
@@ -102,13 +95,11 @@ static enum hrtimer_restart bc_handler(struct hrtimer *t)
{
ce_broadcast_hrtimer.event_handler(&ce_broadcast_hrtimer);

- switch (ce_broadcast_hrtimer.mode) {
- case CLOCK_EVT_MODE_ONESHOT:
+ if (clockevent_state_oneshot(&ce_broadcast_hrtimer))
if (ce_broadcast_hrtimer.next_event.tv64 != KTIME_MAX)
return HRTIMER_RESTART;
- default:
- return HRTIMER_NORESTART;
- }
+
+ return HRTIMER_NORESTART;
}

void tick_setup_hrtimer_broadcast(void)
--
1.9.1

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