[S390] zcrypt: Do not simultaneously schedule hrtimer

Protect the hrtimer ap_poll_timer from being scheduled at the same
time from several processes.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Felix Beck 2009-12-07 12:52:00 +01:00 committed by Martin Schwidefsky
parent 7a6f5cd07e
commit 93521314cb
1 changed files with 8 additions and 3 deletions

View File

@ -102,6 +102,7 @@ static atomic_t ap_poll_requests = ATOMIC_INIT(0);
static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
static struct task_struct *ap_poll_kthread = NULL;
static DEFINE_MUTEX(ap_poll_thread_mutex);
static DEFINE_SPINLOCK(ap_poll_timer_lock);
static void *ap_interrupt_indicator;
static struct hrtimer ap_poll_timer;
/* In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
@ -1170,16 +1171,19 @@ ap_config_timeout(unsigned long ptr)
static inline void ap_schedule_poll_timer(void)
{
ktime_t hr_time;
spin_lock_bh(&ap_poll_timer_lock);
if (ap_using_interrupts() || ap_suspend_flag)
return;
goto out;
if (hrtimer_is_queued(&ap_poll_timer))
return;
goto out;
if (ktime_to_ns(hrtimer_expires_remaining(&ap_poll_timer)) <= 0) {
hr_time = ktime_set(0, poll_timeout);
hrtimer_forward_now(&ap_poll_timer, hr_time);
hrtimer_restart(&ap_poll_timer);
}
return;
out:
spin_unlock_bh(&ap_poll_timer_lock);
}
/**
@ -1668,6 +1672,7 @@ int __init ap_module_init(void)
*/
if (MACHINE_IS_VM)
poll_timeout = 1500000;
spin_lock_init(&ap_poll_timer_lock);
hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
ap_poll_timer.function = ap_poll_timeout;