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Diffstat (limited to 'arch/x86/kernel/irq.c')
-rw-r--r--arch/x86/kernel/irq.c89
1 files changed, 83 insertions, 6 deletions
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 22d0687e7fd..dbb60878b74 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -193,9 +193,13 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
if (!handle_irq(irq, regs)) {
ack_APIC_irq();
- if (printk_ratelimit())
- pr_emerg("%s: %d.%d No irq handler for vector (irq %d)\n",
- __func__, smp_processor_id(), vector, irq);
+ if (irq != VECTOR_RETRIGGERED) {
+ pr_emerg_ratelimited("%s: %d.%d No irq handler for vector (irq %d)\n",
+ __func__, smp_processor_id(),
+ vector, irq);
+ } else {
+ __this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
+ }
}
irq_exit();
@@ -262,6 +266,76 @@ __visible void smp_trace_x86_platform_ipi(struct pt_regs *regs)
EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * This cpu is going to be removed and its vectors migrated to the remaining
+ * online cpus. Check to see if there are enough vectors in the remaining cpus.
+ * This function is protected by stop_machine().
+ */
+int check_irq_vectors_for_cpu_disable(void)
+{
+ int irq, cpu;
+ unsigned int this_cpu, vector, this_count, count;
+ struct irq_desc *desc;
+ struct irq_data *data;
+ struct cpumask affinity_new, online_new;
+
+ this_cpu = smp_processor_id();
+ cpumask_copy(&online_new, cpu_online_mask);
+ cpu_clear(this_cpu, online_new);
+
+ this_count = 0;
+ for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
+ irq = __this_cpu_read(vector_irq[vector]);
+ if (irq >= 0) {
+ desc = irq_to_desc(irq);
+ data = irq_desc_get_irq_data(desc);
+ cpumask_copy(&affinity_new, data->affinity);
+ cpu_clear(this_cpu, affinity_new);
+
+ /* Do not count inactive or per-cpu irqs. */
+ if (!irq_has_action(irq) || irqd_is_per_cpu(data))
+ continue;
+
+ /*
+ * A single irq may be mapped to multiple
+ * cpu's vector_irq[] (for example IOAPIC cluster
+ * mode). In this case we have two
+ * possibilities:
+ *
+ * 1) the resulting affinity mask is empty; that is
+ * this the down'd cpu is the last cpu in the irq's
+ * affinity mask, or
+ *
+ * 2) the resulting affinity mask is no longer
+ * a subset of the online cpus but the affinity
+ * mask is not zero; that is the down'd cpu is the
+ * last online cpu in a user set affinity mask.
+ */
+ if (cpumask_empty(&affinity_new) ||
+ !cpumask_subset(&affinity_new, &online_new))
+ this_count++;
+ }
+ }
+
+ count = 0;
+ for_each_online_cpu(cpu) {
+ if (cpu == this_cpu)
+ continue;
+ for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
+ vector++) {
+ if (per_cpu(vector_irq, cpu)[vector] < 0)
+ count++;
+ }
+ }
+
+ if (count < this_count) {
+ pr_warn("CPU %d disable failed: CPU has %u vectors assigned and there are only %u available.\n",
+ this_cpu, this_count, count);
+ return -ERANGE;
+ }
+ return 0;
+}
+
/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
void fixup_irqs(void)
{
@@ -344,7 +418,7 @@ void fixup_irqs(void)
for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
unsigned int irr;
- if (__this_cpu_read(vector_irq[vector]) < 0)
+ if (__this_cpu_read(vector_irq[vector]) <= VECTOR_UNDEFINED)
continue;
irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
@@ -355,11 +429,14 @@ void fixup_irqs(void)
data = irq_desc_get_irq_data(desc);
chip = irq_data_get_irq_chip(data);
raw_spin_lock(&desc->lock);
- if (chip->irq_retrigger)
+ if (chip->irq_retrigger) {
chip->irq_retrigger(data);
+ __this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
+ }
raw_spin_unlock(&desc->lock);
}
- __this_cpu_write(vector_irq[vector], -1);
+ if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
+ __this_cpu_write(vector_irq[vector], VECTOR_UNDEFINED);
}
}
#endif