diff options
Diffstat (limited to 'drivers/xen/events/events_fifo.c')
| -rw-r--r-- | drivers/xen/events/events_fifo.c | 45 |
1 files changed, 40 insertions, 5 deletions
diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c index ed673e1acd61..6df8aac966b9 100644 --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -255,6 +255,12 @@ static void evtchn_fifo_unmask(unsigned port) } } +static bool evtchn_fifo_is_linked(unsigned port) +{ + event_word_t *word = event_word_from_port(port); + return sync_test_bit(EVTCHN_FIFO_BIT(LINKED, word), BM(word)); +} + static uint32_t clear_linked(volatile event_word_t *word) { event_word_t new, old, w; @@ -281,7 +287,8 @@ static void handle_irq_for_port(unsigned port) static void consume_one_event(unsigned cpu, struct evtchn_fifo_control_block *control_block, - unsigned priority, unsigned long *ready) + unsigned priority, unsigned long *ready, + bool drop) { struct evtchn_fifo_queue *q = &per_cpu(cpu_queue, cpu); uint32_t head; @@ -313,13 +320,15 @@ static void consume_one_event(unsigned cpu, if (head == 0) clear_bit(priority, ready); - if (evtchn_fifo_is_pending(port) && !evtchn_fifo_is_masked(port)) - handle_irq_for_port(port); + if (evtchn_fifo_is_pending(port) && !evtchn_fifo_is_masked(port)) { + if (likely(!drop)) + handle_irq_for_port(port); + } q->head[priority] = head; } -static void evtchn_fifo_handle_events(unsigned cpu) +static void __evtchn_fifo_handle_events(unsigned cpu, bool drop) { struct evtchn_fifo_control_block *control_block; unsigned long ready; @@ -331,11 +340,16 @@ static void evtchn_fifo_handle_events(unsigned cpu) while (ready) { q = find_first_bit(&ready, EVTCHN_FIFO_MAX_QUEUES); - consume_one_event(cpu, control_block, q, &ready); + consume_one_event(cpu, control_block, q, &ready, drop); ready |= xchg(&control_block->ready, 0); } } +static void evtchn_fifo_handle_events(unsigned cpu) +{ + __evtchn_fifo_handle_events(cpu, false); +} + static void evtchn_fifo_resume(void) { unsigned cpu; @@ -371,6 +385,26 @@ static void evtchn_fifo_resume(void) event_array_pages = 0; } +static void evtchn_fifo_close(unsigned port, unsigned int cpu) +{ + if (cpu == NR_CPUS) + return; + + get_online_cpus(); + if (cpu_online(cpu)) { + if (WARN_ON(irqs_disabled())) + goto out; + + while (evtchn_fifo_is_linked(port)) + cpu_relax(); + } else { + __evtchn_fifo_handle_events(cpu, true); + } + +out: + put_online_cpus(); +} + static const struct evtchn_ops evtchn_ops_fifo = { .max_channels = evtchn_fifo_max_channels, .nr_channels = evtchn_fifo_nr_channels, @@ -384,6 +418,7 @@ static const struct evtchn_ops evtchn_ops_fifo = { .unmask = evtchn_fifo_unmask, .handle_events = evtchn_fifo_handle_events, .resume = evtchn_fifo_resume, + .close = evtchn_fifo_close, }; static int evtchn_fifo_alloc_control_block(unsigned cpu) |