aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/irq.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/irq.c')
-rw-r--r--arch/x86/kernel/irq.c44
1 files changed, 35 insertions, 9 deletions
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index dbb60878b74..922d2858102 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -17,6 +17,7 @@
#include <asm/idle.h>
#include <asm/mce.h>
#include <asm/hw_irq.h>
+#include <asm/desc.h>
#define CREATE_TRACE_POINTS
#include <asm/trace/irq_vectors.h>
@@ -125,6 +126,12 @@ int arch_show_interrupts(struct seq_file *p, int prec)
seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
seq_printf(p, " Machine check polls\n");
#endif
+#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+ seq_printf(p, "%*s: ", prec, "THR");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_hv_callback_count);
+ seq_printf(p, " Hypervisor callback interrupts\n");
+#endif
seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
#if defined(CONFIG_X86_IO_APIC)
seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
@@ -266,6 +273,14 @@ __visible void smp_trace_x86_platform_ipi(struct pt_regs *regs)
EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
#ifdef CONFIG_HOTPLUG_CPU
+
+/* These two declarations are only used in check_irq_vectors_for_cpu_disable()
+ * below, which is protected by stop_machine(). Putting them on the stack
+ * results in a stack frame overflow. Dynamically allocating could result in a
+ * failure so declare these two cpumasks as global.
+ */
+static struct cpumask affinity_new, online_new;
+
/*
* 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.
@@ -277,7 +292,6 @@ int check_irq_vectors_for_cpu_disable(void)
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);
@@ -321,10 +335,17 @@ int check_irq_vectors_for_cpu_disable(void)
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++;
+ /*
+ * We scan from FIRST_EXTERNAL_VECTOR to first system
+ * vector. If the vector is marked in the used vectors
+ * bitmap or an irq is assigned to it, we don't count
+ * it as available.
+ */
+ for (vector = FIRST_EXTERNAL_VECTOR;
+ vector < first_system_vector; vector++) {
+ if (!test_bit(vector, used_vectors) &&
+ per_cpu(vector_irq, cpu)[vector] < 0)
+ count++;
}
}
@@ -344,6 +365,7 @@ void fixup_irqs(void)
struct irq_desc *desc;
struct irq_data *data;
struct irq_chip *chip;
+ int ret;
for_each_irq_desc(irq, desc) {
int break_affinity = 0;
@@ -382,10 +404,14 @@ void fixup_irqs(void)
if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
chip->irq_mask(data);
- if (chip->irq_set_affinity)
- chip->irq_set_affinity(data, affinity, true);
- else if (!(warned++))
- set_affinity = 0;
+ if (chip->irq_set_affinity) {
+ ret = chip->irq_set_affinity(data, affinity, true);
+ if (ret == -ENOSPC)
+ pr_crit("IRQ %d set affinity failed because there are no available vectors. The device assigned to this IRQ is unstable.\n", irq);
+ } else {
+ if (!(warned++))
+ set_affinity = 0;
+ }
/*
* We unmask if the irq was not marked masked by the