From 6cb6537d34a146c8f3e232da9ffd79ae1265fed3 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Thu, 10 Mar 2011 16:08:11 +0000 Subject: xen: events: maintain a list of Xen interrupts In a PVHVM kernel not all interrupts are Xen interrupts (APIC interrupts can also be present). Currently we get away with walking over all interrupts because the lookup in the irq_info array simply returns IRQT_UNBOUND and we ignore it. However this array will be going away in a future patch so we need to manually track which interrupts have been allocated by the Xen events infrastructure. Signed-off-by: Ian Campbell Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/events.c | 59 +++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 44 insertions(+), 15 deletions(-) (limited to 'drivers/xen') diff --git a/drivers/xen/events.c b/drivers/xen/events.c index cf372d41077d..e119989ec15b 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -56,6 +56,8 @@ */ static DEFINE_SPINLOCK(irq_mapping_update_lock); +static LIST_HEAD(xen_irq_list_head); + /* IRQ <-> VIRQ mapping. */ static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1}; @@ -85,7 +87,9 @@ enum xen_irq_type { */ struct irq_info { + struct list_head list; enum xen_irq_type type; /* type */ + unsigned irq; unsigned short evtchn; /* event channel */ unsigned short cpu; /* cpu bound */ @@ -135,6 +139,7 @@ static void xen_irq_info_common_init(struct irq_info *info, BUG_ON(info->type != IRQT_UNBOUND && info->type != type); info->type = type; + info->irq = irq; info->evtchn = evtchn; info->cpu = cpu; @@ -311,10 +316,11 @@ static void init_evtchn_cpu_bindings(void) { int i; #ifdef CONFIG_SMP - struct irq_desc *desc; + struct irq_info *info; /* By default all event channels notify CPU#0. */ - for_each_irq_desc(i, desc) { + list_for_each_entry(info, &xen_irq_list_head, list) { + struct irq_desc *desc = irq_to_desc(info->irq); cpumask_copy(desc->irq_data.affinity, cpumask_of(0)); } #endif @@ -397,6 +403,21 @@ static void unmask_evtchn(int port) put_cpu(); } +static void xen_irq_init(unsigned irq) +{ + struct irq_info *info; + struct irq_desc *desc = irq_to_desc(irq); + + /* By default all event channels notify CPU#0. */ + cpumask_copy(desc->irq_data.affinity, cpumask_of(0)); + + info = &irq_info[irq]; + + info->type = IRQT_UNBOUND; + + list_add_tail(&info->list, &xen_irq_list_head); +} + static int xen_allocate_irq_dynamic(void) { int first = 0; @@ -426,6 +447,8 @@ retry: if (irq < 0) panic("No available IRQ to bind to: increase nr_irqs!\n"); + xen_irq_init(irq); + return irq; } @@ -444,18 +467,25 @@ static int xen_allocate_irq_gsi(unsigned gsi) /* Legacy IRQ descriptors are already allocated by the arch. */ if (gsi < NR_IRQS_LEGACY) - return gsi; + irq = gsi; + else + irq = irq_alloc_desc_at(gsi, -1); - irq = irq_alloc_desc_at(gsi, -1); if (irq < 0) panic("Unable to allocate to IRQ%d (%d)\n", gsi, irq); + xen_irq_init(irq); + return irq; } static void xen_free_irq(unsigned irq) { - irq_info[irq].type = IRQT_UNBOUND; + struct irq_info *info = &irq_info[irq]; + + info->type = IRQT_UNBOUND; + + list_del(&info->list); /* Legacy IRQ descriptors are managed by the arch. */ if (irq < NR_IRQS_LEGACY) @@ -586,16 +616,14 @@ static void ack_pirq(struct irq_data *data) static int find_irq_by_gsi(unsigned gsi) { - int irq; - - for (irq = 0; irq < nr_irqs; irq++) { - struct irq_info *info = info_for_irq(irq); + struct irq_info *info; - if (info == NULL || info->type != IRQT_PIRQ) + list_for_each_entry(info, &xen_irq_list_head, list) { + if (info->type != IRQT_PIRQ) continue; - if (gsi_from_irq(irq) == gsi) - return irq; + if (info->u.pirq.gsi == gsi) + return info->irq; } return -1; @@ -1374,7 +1402,8 @@ void xen_poll_irq(int irq) void xen_irq_resume(void) { - unsigned int cpu, irq, evtchn; + unsigned int cpu, evtchn; + struct irq_info *info; init_evtchn_cpu_bindings(); @@ -1383,8 +1412,8 @@ void xen_irq_resume(void) mask_evtchn(evtchn); /* No IRQ <-> event-channel mappings. */ - for (irq = 0; irq < nr_irqs; irq++) - irq_info[irq].evtchn = 0; /* zap event-channel binding */ + list_for_each_entry(info, &xen_irq_list_head, list) + info->evtchn = 0; /* zap event-channel binding */ for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++) evtchn_to_irq[evtchn] = -1; -- cgit v1.2.3-59-g8ed1b