From 93521314cb3132f40a4bf6d76b4bbcdbc9e59dfb Mon Sep 17 00:00:00 2001 From: Felix Beck Date: Mon, 7 Dec 2009 12:52:00 +0100 Subject: [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 Signed-off-by: Martin Schwidefsky --- drivers/s390/crypto/ap_bus.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/s390') diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index 21077f4b8c5..20836eff88c 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -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; -- cgit v1.2.3-18-g5258