x86/irq: Store irq descriptor in vector array
We can spare the irq_desc lookup in the interrupt entry code if we
store the descriptor pointer in the vector array instead the interrupt
number.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/20150802203609.717724106@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 9a6d112..200b5a5 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -169,7 +169,7 @@
goto next;
for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask) {
- if (per_cpu(vector_irq, new_cpu)[vector] > VECTOR_UNUSED)
+ if (!IS_ERR_OR_NULL(per_cpu(vector_irq, new_cpu)[vector]))
goto next;
}
/* Found one! */
@@ -181,7 +181,7 @@
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;
@@ -223,8 +223,9 @@
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);
@@ -241,10 +242,11 @@
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_UNUSED;
break;
@@ -402,30 +404,30 @@
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_UNUSED)
+ 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_UNUSED;
}
@@ -447,7 +449,7 @@
* 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);
}
@@ -543,19 +545,13 @@
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;
retry:
- irq = __this_cpu_read(vector_irq[vector]);
-
- if (irq <= VECTOR_UNUSED)
- continue;
-
- desc = irq_to_desc(irq);
- if (!desc)
+ desc = __this_cpu_read(vector_irq[vector]);
+ if (IS_ERR_OR_NULL(desc))
continue;
if (!raw_spin_trylock(&desc->lock)) {
@@ -565,9 +561,10 @@
goto retry;
}
- data = apic_chip_data(&desc->irq_data);
+ data = apic_chip_data(irq_desc_get_irq_data(desc));
if (!data)
goto unlock;
+
/*
* Check if the irq migration is in progress. If so, we
* haven't received the cleanup request yet for this irq.