From 433cbd57d190a1cdd02f243df41c3d7f55ec4b94 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 31 Dec 2015 16:30:46 +0000 Subject: [PATCH] x86/irq: Reorganize the return path in assign_irq_vector Use an explicit goto for the cases where we have success in the search/update and return -ENOSPC if the search loop ends due to no space. Preparatory patch for fixes. No functional change. Signed-off-by: Thomas Gleixner Tested-by: Borislav Petkov Tested-by: Joe Lawrence Cc: Jiang Liu Cc: Jeremiah Mahler Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.403491024@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/kernel/apic/vector.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index 19082cf56616..613b1cd8eecb 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -118,13 +118,12 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d, */ static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START; static int current_offset = VECTOR_OFFSET_START % 16; - int cpu, err; + int cpu; if (d->move_in_progress) return -EBUSY; /* Only try and allocate irqs on cpus that are present */ - err = -ENOSPC; cpumask_clear(d->old_domain); cpumask_clear(searched_cpumask); cpu = cpumask_first_and(mask, cpu_online_mask); @@ -134,9 +133,8 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d, apic->vector_allocation_domain(cpu, vector_cpumask, mask); if (cpumask_subset(vector_cpumask, d->domain)) { - err = 0; if (cpumask_equal(vector_cpumask, d->domain)) - break; + goto success; /* * New cpumask using the vector is a proper subset of * the current in use mask. So cleanup the vector @@ -147,7 +145,7 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d, d->move_in_progress = cpumask_intersects(d->old_domain, cpu_online_mask); cpumask_and(d->domain, d->domain, vector_cpumask); - break; + goto success; } vector = current_vector; @@ -187,17 +185,13 @@ next: per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq); d->cfg.vector = vector; cpumask_copy(d->domain, vector_cpumask); - err = 0; - break; + goto success; } + return -ENOSPC; - if (!err) { - /* cache destination APIC IDs into cfg->dest_apicid */ - err = apic->cpu_mask_to_apicid_and(mask, d->domain, - &d->cfg.dest_apicid); - } - - return err; +success: + /* cache destination APIC IDs into cfg->dest_apicid */ + return apic->cpu_mask_to_apicid_and(mask, d->domain, &d->cfg.dest_apicid); } static int assign_irq_vector(int irq, struct apic_chip_data *data, -- 2.30.2