static void
xpc_start_hb_beater(void)
{
xpc_heartbeat_init();
init_timer(&xpc_hb_timer);
xpc_hb_timer.function = xpc_hb_beater;
xpc_hb_beater(0);
}
/*
* This thread is responsible for nearly all of the partition
* activation/deactivation.
*/
static int
xpc_hb_checker(void *ignore)
{
int last_IRQ_count = 0;
int new_IRQ_count;
int force_IRQ = 0;
/* this thread was marked active by xpc_hb_init() */
set_cpus_allowed(current, cpumask_of_cpu(XPC_HB_CHECK_CPU));
/* set our heartbeating to other partitions into motion */
xpc_hb_check_timeout = jiffies + (xpc_hb_check_interval * HZ);
xpc_hb_beater(0);
while (!xpc_exiting) {
dev_dbg(xpc_part, "woke up with %d ticks rem; %d IRQs have "
"been received\n",
(int)(xpc_hb_check_timeout - jiffies),
atomic_read(&xpc_act_IRQ_rcvd) - last_IRQ_count);
/* checking of remote heartbeats is skewed by IRQ handling */
if (time_after_eq(jiffies, xpc_hb_check_timeout)) {
dev_dbg(xpc_part, "checking remote heartbeats\n");
xpc_check_remote_hb();
/*
* We need to periodically recheck to ensure no
* IPI/AMO pairs have been missed. That check
* must always reset xpc_hb_check_timeout.
*/
force_IRQ = 1;
}
/* check for outstanding IRQs */
new_IRQ_count = atomic_read(&xpc_act_IRQ_rcvd);
if (last_IRQ_count < new_IRQ_count || force_IRQ != 0) {
force_IRQ = 0;
dev_dbg(xpc_part, "found an IRQ to process; will be "
"resetting xpc_hb_check_timeout\n");
last_IRQ_count += xpc_identify_act_IRQ_sender();
if (last_IRQ_count < new_IRQ_count) {
/* retry once to help avoid missing AMO */
(void)xpc_identify_act_IRQ_sender();
}
last_IRQ_count = new_IRQ_count;
xpc_hb_check_timeout = jiffies +
(xpc_hb_check_interval * HZ);
}
/* wait for IRQ or timeout */
(void)wait_event_interruptible(xpc_act_IRQ_wq,
(last_IRQ_count <
atomic_read(&xpc_act_IRQ_rcvd)
|| time_after_eq(jiffies,
xpc_hb_check_timeout) ||
xpc_exiting));
}
dev_dbg(xpc_part, "heartbeat checker is exiting\n");
/* mark this thread as having exited */
complete(&xpc_hb_checker_exited);
return 0;
}
