Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 apic updates from Thomas Gleixner:
 "This udpate contains:

   - rework the irq vector array to store a pointer to the irq
     descriptor instead of the irq number to avoid a lookup of the irq
     descriptor in the irq entry path

   - lguest interrupt handling cleanups

   - conversion of the local apic timer to the new clockevent callbacks

   - preparatory changes for the irq argument removal of interrupt flow
     handlers"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/irq: Do not dereference irq descriptor before checking it
  tools/lguest: Clean up include dir
  tools/lguest: Fix redefinition of struct virtio_pci_cfg_cap
  x86/irq: Store irq descriptor in vector array
  genirq: Provide irq_desc_has_action
  x86/irq: Get rid of an indentation level
  x86/irq: Rename VECTOR_UNDEFINED to VECTOR_UNUSED
  x86/irq: Replace numeric constant
  x86/irq: Protect smp_cleanup_move
  x86/lguest: Do not setup unused irq vectors
  x86/lguest: Clean up lguest_setup_irq
  x86/apic: Drop local_irq_save/restore in timer callbacks
  x86/apic: Migrate apic timer to new set_state interface
  x86/irq: Use access helper irq_data_get_affinity_mask()
  x86/irq: Use accessor irq_data_get_irq_handler_data()
  x86/irq: Use accessor irq_data_get_node()

Author: torvalds

arch/x86/include/asm/hw_irq.h

@@ -182,10 +182,10 @@ extern char irq_entries_start[];
 #define trace_irq_entries_start irq_entries_start
 #endif
 
-#define VECTOR_UNDEFINED	(-1)
-#define VECTOR_RETRIGGERED	(-2)
+#define VECTOR_UNUSED		NULL
+#define VECTOR_RETRIGGERED	((void *)~0UL)
 
-typedef int vector_irq_t[NR_VECTORS];
+typedef struct irq_desc* vector_irq_t[NR_VECTORS];
 DECLARE_PER_CPU(vector_irq_t, vector_irq);
 
 #endif /* !ASSEMBLY_ */

arch/x86/include/asm/irq.h

@@ -36,7 +36,9 @@ extern void kvm_set_posted_intr_wakeup_handler(void (*handler)(void));
 
 extern void (*x86_platform_ipi_callback)(void);
 extern void native_init_IRQ(void);
-extern bool handle_irq(unsigned irq, struct pt_regs *regs);
+
+struct irq_desc;
+extern bool handle_irq(struct irq_desc *desc, struct pt_regs *regs);
 
 extern __visible unsigned int do_IRQ(struct pt_regs *regs);
 

arch/x86/kernel/apic/apic.c

@@ -462,40 +462,40 @@ static int lapic_next_deadline(unsigned long delta,
 	return 0;
 }
 
-/*
- * Setup the lapic timer in periodic or oneshot mode
- */
-static void lapic_timer_setup(enum clock_event_mode mode,
-			      struct clock_event_device *evt)
+static int lapic_timer_shutdown(struct clock_event_device *evt)
 {
-	unsigned long flags;
 	unsigned int v;
 
 	/* Lapic used as dummy for broadcast ? */
 	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
-		return;
+		return 0;
 
-	local_irq_save(flags);
+	v = apic_read(APIC_LVTT);
+	v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+	apic_write(APIC_LVTT, v);
+	apic_write(APIC_TMICT, 0);
+	return 0;
+}
 
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-	case CLOCK_EVT_MODE_ONESHOT:
-		__setup_APIC_LVTT(lapic_timer_frequency,
-				  mode != CLOCK_EVT_MODE_PERIODIC, 1);
-		break;
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_SHUTDOWN:
-		v = apic_read(APIC_LVTT);
-		v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
-		apic_write(APIC_LVTT, v);
-		apic_write(APIC_TMICT, 0);
-		break;
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
+static inline int
+lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
+{
+	/* Lapic used as dummy for broadcast ? */
+	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
+		return 0;
 
-	local_irq_restore(flags);
+	__setup_APIC_LVTT(lapic_timer_frequency, oneshot, 1);
+	return 0;
+}
+
+static int lapic_timer_set_periodic(struct clock_event_device *evt)
+{
+	return lapic_timer_set_periodic_oneshot(evt, false);
+}
+
+static int lapic_timer_set_oneshot(struct clock_event_device *evt)
+{
+	return lapic_timer_set_periodic_oneshot(evt, true);
 }
 
 /*
@@ -513,15 +513,18 @@ static void lapic_timer_broadcast(const struct cpumask *mask)
  * The local apic timer can be used for any function which is CPU local.
  */
 static struct clock_event_device lapic_clockevent = {
-	.name		= "lapic",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
-			| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
-	.shift		= 32,
-	.set_mode	= lapic_timer_setup,
-	.set_next_event	= lapic_next_event,
-	.broadcast	= lapic_timer_broadcast,
-	.rating		= 100,
-	.irq		= -1,
+	.name			= "lapic",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
+				  | CLOCK_EVT_FEAT_DUMMY,
+	.shift			= 32,
+	.set_state_shutdown	= lapic_timer_shutdown,
+	.set_state_periodic	= lapic_timer_set_periodic,
+	.set_state_oneshot	= lapic_timer_set_oneshot,
+	.set_next_event		= lapic_next_event,
+	.broadcast		= lapic_timer_broadcast,
+	.rating			= 100,
+	.irq			= -1,
 };
 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
 
@@ -778,7 +781,7 @@ static int __init calibrate_APIC_clock(void)
 		 * Setup the apic timer manually
 		 */
 		levt->event_handler = lapic_cal_handler;
-		lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
+		lapic_timer_set_periodic(levt);
 		lapic_cal_loops = -1;
 
 		/* Let the interrupts run */
@@ -788,7 +791,8 @@ static int __init calibrate_APIC_clock(void)
 			cpu_relax();
 
 		/* Stop the lapic timer */
-		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
+		local_irq_disable();
+		lapic_timer_shutdown(levt);
 
 		/* Jiffies delta */
 		deltaj = lapic_cal_j2 - lapic_cal_j1;
@@ -799,8 +803,8 @@ static int __init calibrate_APIC_clock(void)
 			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
 		else
 			levt->features |= CLOCK_EVT_FEAT_DUMMY;
-	} else
-		local_irq_enable();
+	}
+	local_irq_enable();
 
 	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
 		pr_warning("APIC timer disabled due to verification failure\n");
@@ -878,7 +882,7 @@ static void local_apic_timer_interrupt(void)
 	if (!evt->event_handler) {
 		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
 		/* Switch it off */
-		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
+		lapic_timer_shutdown(evt);
 		return;
 	}
 

arch/x86/kernel/apic/io_apic.c

@@ -2541,7 +2541,7 @@ void __init setup_ioapic_dest(void)
 		 * Honour affinities which have been set in early boot
 		 */
 		if (!irqd_can_balance(idata) || irqd_affinity_was_set(idata))
-			mask = idata->affinity;
+			mask = irq_data_get_affinity_mask(idata);
 		else
 			mask = apic->target_cpus();
 

arch/x86/kernel/apic/msi.c

@@ -264,7 +264,7 @@ static inline int hpet_dev_id(struct irq_domain *domain)
 
 static void hpet_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
 {
-	hpet_msi_write(data->handler_data, msg);
+	hpet_msi_write(irq_data_get_irq_handler_data(data), msg);
 }
 
 static struct irq_chip hpet_msi_controller = {

arch/x86/kernel/apic/vector.c

@@ -169,8 +169,7 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d,
 			goto next;
 
 		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask) {
-			if (per_cpu(vector_irq, new_cpu)[vector] >
-			    VECTOR_UNDEFINED)
+			if (!IS_ERR_OR_NULL(per_cpu(vector_irq, new_cpu)[vector]))
 				goto next;
 		}
 		/* Found one! */
@@ -182,7 +181,7 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d,
 			   cpumask_intersects(d->old_domain, cpu_online_mask);
 		}
 		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask)
-			per_cpu(vector_irq, new_cpu)[vector] = irq;
+			per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq);
 		d->cfg.vector = vector;
 		cpumask_copy(d->domain, vector_cpumask);
 		err = 0;
@@ -224,15 +223,16 @@ static int assign_irq_vector_policy(int irq, int node,
 
 static void clear_irq_vector(int irq, struct apic_chip_data *data)
 {
-	int cpu, vector;
+	struct irq_desc *desc;
 	unsigned long flags;
+	int cpu, vector;
 
 	raw_spin_lock_irqsave(&vector_lock, flags);
 	BUG_ON(!data->cfg.vector);
 
 	vector = data->cfg.vector;
 	for_each_cpu_and(cpu, data->domain, cpu_online_mask)
-		per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+		per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
 
 	data->cfg.vector = 0;
 	cpumask_clear(data->domain);
@@ -242,12 +242,13 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
 		return;
 	}
 
+	desc = irq_to_desc(irq);
 	for_each_cpu_and(cpu, data->old_domain, cpu_online_mask) {
 		for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
 		     vector++) {
-			if (per_cpu(vector_irq, cpu)[vector] != irq)
+			if (per_cpu(vector_irq, cpu)[vector] != desc)
 				continue;
-			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
 			break;
 		}
 	}
@@ -296,7 +297,7 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
 	struct irq_alloc_info *info = arg;
 	struct apic_chip_data *data;
 	struct irq_data *irq_data;
-	int i, err;
+	int i, err, node;
 
 	if (disable_apic)
 		return -ENXIO;
@@ -308,12 +309,13 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
 	for (i = 0; i < nr_irqs; i++) {
 		irq_data = irq_domain_get_irq_data(domain, virq + i);
 		BUG_ON(!irq_data);
+		node = irq_data_get_node(irq_data);
 #ifdef	CONFIG_X86_IO_APIC
 		if (virq + i < nr_legacy_irqs() && legacy_irq_data[virq + i])
 			data = legacy_irq_data[virq + i];
 		else
 #endif
-			data = alloc_apic_chip_data(irq_data->node);
+			data = alloc_apic_chip_data(node);
 		if (!data) {
 			err = -ENOMEM;
 			goto error;
@@ -322,8 +324,7 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
 		irq_data->chip = &lapic_controller;
 		irq_data->chip_data = data;
 		irq_data->hwirq = virq + i;
-		err = assign_irq_vector_policy(virq + i, irq_data->node, data,
-					       info);
+		err = assign_irq_vector_policy(virq + i, node, data, info);
 		if (err)
 			goto error;
 	}
@@ -403,32 +404,32 @@ int __init arch_early_irq_init(void)
 	return arch_early_ioapic_init();
 }
 
+/* Initialize vector_irq on a new cpu */
 static void __setup_vector_irq(int cpu)
 {
-	/* Initialize vector_irq on a new cpu */
-	int irq, vector;
 	struct apic_chip_data *data;
+	struct irq_desc *desc;
+	int irq, vector;
 
 	/* Mark the inuse vectors */
-	for_each_active_irq(irq) {
-		data = apic_chip_data(irq_get_irq_data(irq));
-		if (!data)
-			continue;
+	for_each_irq_desc(irq, desc) {
+		struct irq_data *idata = irq_desc_get_irq_data(desc);
 
-		if (!cpumask_test_cpu(cpu, data->domain))
+		data = apic_chip_data(idata);
+		if (!data || !cpumask_test_cpu(cpu, data->domain))
 			continue;
 		vector = data->cfg.vector;
-		per_cpu(vector_irq, cpu)[vector] = irq;
+		per_cpu(vector_irq, cpu)[vector] = desc;
 	}
 	/* Mark the free vectors */
 	for (vector = 0; vector < NR_VECTORS; ++vector) {
-		irq = per_cpu(vector_irq, cpu)[vector];
-		if (irq <= VECTOR_UNDEFINED)
+		desc = per_cpu(vector_irq, cpu)[vector];
+		if (IS_ERR_OR_NULL(desc))
 			continue;
 
-		data = apic_chip_data(irq_get_irq_data(irq));
+		data = apic_chip_data(irq_desc_get_irq_data(desc));
 		if (!cpumask_test_cpu(cpu, data->domain))
-			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
+			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
 	}
 }
 
@@ -448,7 +449,7 @@ void setup_vector_irq(int cpu)
 	 * legacy vector to irq mapping:
 	 */
 	for (irq = 0; irq < nr_legacy_irqs(); irq++)
-		per_cpu(vector_irq, cpu)[ISA_IRQ_VECTOR(irq)] = irq;
+		per_cpu(vector_irq, cpu)[ISA_IRQ_VECTOR(irq)] = irq_to_desc(irq);
 
 	__setup_vector_irq(cpu);
 }
@@ -490,7 +491,8 @@ static int apic_set_affinity(struct irq_data *irq_data,
 	if (err) {
 		struct irq_data *top = irq_get_irq_data(irq);
 
-		if (assign_irq_vector(irq, data, top->affinity))
+		if (assign_irq_vector(irq, data,
+				      irq_data_get_affinity_mask(top)))
 			pr_err("Failed to recover vector for irq %d\n", irq);
 		return err;
 	}
@@ -538,27 +540,30 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 
 	entering_ack_irq();
 
+	/* Prevent vectors vanishing under us */
+	raw_spin_lock(&vector_lock);
+
 	me = smp_processor_id();
 	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
-		int irq;
-		unsigned int irr;
-		struct irq_desc *desc;
 		struct apic_chip_data *data;
+		struct irq_desc *desc;
+		unsigned int irr;
 
-		irq = __this_cpu_read(vector_irq[vector]);
-
-		if (irq <= VECTOR_UNDEFINED)
+	retry:
+		desc = __this_cpu_read(vector_irq[vector]);
+		if (IS_ERR_OR_NULL(desc))
 			continue;
 
-		desc = irq_to_desc(irq);
-		if (!desc)
-			continue;
+		if (!raw_spin_trylock(&desc->lock)) {
+			raw_spin_unlock(&vector_lock);
+			cpu_relax();
+			raw_spin_lock(&vector_lock);
+			goto retry;
+		}
 
-		data = apic_chip_data(&desc->irq_data);
+		data = apic_chip_data(irq_desc_get_irq_data(desc));
 		if (!data)
-			continue;
-
-		raw_spin_lock(&desc->lock);
+			goto unlock;
 
 		/*
 		 * Check if the irq migration is in progress. If so, we
@@ -583,11 +588,13 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 			apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
 			goto unlock;
 		}
-		__this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
+		__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
 unlock:
 		raw_spin_unlock(&desc->lock);
 	}
 
+	raw_spin_unlock(&vector_lock);
+
 	exiting_irq();
 }