From a782a7e46bb50822fabfeb7271605762a59c86df Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 2 Aug 2015 20:38:27 +0000 Subject: 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 Cc: Jiang Liu Cc: Peter Zijlstra Cc: Rusty Russell Cc: Bjorn Helgaas Link: http://lkml.kernel.org/r/20150802203609.717724106@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/kernel/irq.c | 37 ++++++++++++++++--------------------- 1 file changed, 16 insertions(+), 21 deletions(-) (limited to 'arch/x86/kernel/irq.c') diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index 140950fb9902..e010847583d7 100644 --- a/arch/x86/kernel/irq.c +++ b/arch/x86/kernel/irq.c @@ -211,22 +211,21 @@ u64 arch_irq_stat(void) __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); - + struct irq_desc * desc; /* high bit used in ret_from_ code */ unsigned vector = ~regs->orig_ax; - unsigned irq; entering_irq(); - irq = __this_cpu_read(vector_irq[vector]); + desc = __this_cpu_read(vector_irq[vector]); - if (!handle_irq(irq, regs)) { + if (!handle_irq(desc, regs)) { ack_APIC_irq(); - if (irq != VECTOR_RETRIGGERED) { - pr_emerg_ratelimited("%s: %d.%d No irq handler for vector (irq %d)\n", + if (desc != VECTOR_RETRIGGERED) { + pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n", __func__, smp_processor_id(), - vector, irq); + vector); } else { __this_cpu_write(vector_irq[vector], VECTOR_UNUSED); } @@ -330,10 +329,10 @@ static struct cpumask affinity_new, online_new; */ 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; + int cpu; this_cpu = smp_processor_id(); cpumask_copy(&online_new, cpu_online_mask); @@ -341,24 +340,21 @@ int check_irq_vectors_for_cpu_disable(void) this_count = 0; for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) { - irq = __this_cpu_read(vector_irq[vector]); - if (irq < 0) - continue; - desc = irq_to_desc(irq); - if (!desc) + desc = __this_cpu_read(vector_irq[vector]); + if (IS_ERR_OR_NULL(desc)) continue; - /* * Protect against concurrent action removal, affinity * changes etc. */ raw_spin_lock(&desc->lock); data = irq_desc_get_irq_data(desc); - cpumask_copy(&affinity_new, irq_data_get_affinity_mask(data)); + cpumask_copy(&affinity_new, + irq_data_get_affinity_mask(data)); cpumask_clear_cpu(this_cpu, &affinity_new); /* Do not count inactive or per-cpu irqs. */ - if (!irq_has_action(irq) || irqd_is_per_cpu(data)) { + if (!irq_desc_has_action(desc) || irqd_is_per_cpu(data)) { raw_spin_unlock(&desc->lock); continue; } @@ -399,8 +395,8 @@ int check_irq_vectors_for_cpu_disable(void) for (vector = FIRST_EXTERNAL_VECTOR; vector < first_system_vector; vector++) { if (!test_bit(vector, used_vectors) && - per_cpu(vector_irq, cpu)[vector] <= VECTOR_UNUSED) - count++; + IS_ERR_OR_NULL(per_cpu(vector_irq, cpu)[vector])) + count++; } } @@ -504,14 +500,13 @@ void fixup_irqs(void) for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) { unsigned int irr; - if (__this_cpu_read(vector_irq[vector]) <= VECTOR_UNUSED) + if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector]))) continue; irr = apic_read(APIC_IRR + (vector / 32 * 0x10)); if (irr & (1 << (vector % 32))) { - irq = __this_cpu_read(vector_irq[vector]); + desc = __this_cpu_read(vector_irq[vector]); - desc = irq_to_desc(irq); raw_spin_lock(&desc->lock); data = irq_desc_get_irq_data(desc); chip = irq_data_get_irq_chip(data); -- cgit v1.2.3