| From dffa32bd8dcb5aaf464d09d71c79c2eb08fea1d9 Mon Sep 17 00:00:00 2001 |
| From: Thomas Gleixner <tglx@linutronix.de> |
| Date: Fri, 25 May 2012 16:59:47 +0200 |
| Subject: [PATCH 247/274] genirq: Add default affinity mask command line |
| option |
| |
| If we isolate CPUs, then we don't want random device interrupts on |
| them. Even w/o the user space irq balancer enabled we can end up with |
| irqs on non boot cpus. |
| |
| Allow to restrict the default irq affinity mask. |
| |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| --- |
| Documentation/kernel-parameters.txt | 9 +++++++++ |
| kernel/irq/irqdesc.c | 21 +++++++++++++++++++-- |
| 2 files changed, 28 insertions(+), 2 deletions(-) |
| |
| diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt |
| index 1e0150e..67d1350 100644 |
| --- a/Documentation/kernel-parameters.txt |
| +++ b/Documentation/kernel-parameters.txt |
| @@ -1126,6 +1126,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted. |
| See comment before ip2_setup() in |
| drivers/char/ip2/ip2base.c. |
| |
| + irqaffinity= [SMP] Set the default irq affinity mask |
| + Format: |
| + <cpu number>,...,<cpu number> |
| + or |
| + <cpu number>-<cpu number> |
| + (must be a positive range in ascending order) |
| + or a mixture |
| + <cpu number>,...,<cpu number>-<cpu number> |
| + |
| irqfixup [HW] |
| When an interrupt is not handled search all handlers |
| for it. Intended to get systems with badly broken |
| diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c |
| index 192a302..473b2b6 100644 |
| --- a/kernel/irq/irqdesc.c |
| +++ b/kernel/irq/irqdesc.c |
| @@ -23,10 +23,27 @@ |
| static struct lock_class_key irq_desc_lock_class; |
| |
| #if defined(CONFIG_SMP) |
| +static int __init irq_affinity_setup(char *str) |
| +{ |
| + zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); |
| + cpulist_parse(str, irq_default_affinity); |
| + /* |
| + * Set at least the boot cpu. We don't want to end up with |
| + * bugreports caused by random comandline masks |
| + */ |
| + cpumask_set_cpu(smp_processor_id(), irq_default_affinity); |
| + return 1; |
| +} |
| +__setup("irqaffinity=", irq_affinity_setup); |
| + |
| static void __init init_irq_default_affinity(void) |
| { |
| - alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); |
| - cpumask_setall(irq_default_affinity); |
| +#ifdef CONFIG_CPUMASK_OFFSTACK |
| + if (!irq_default_affinity) |
| + zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); |
| +#endif |
| + if (cpumask_empty(irq_default_affinity)) |
| + cpumask_setall(irq_default_affinity); |
| } |
| #else |
| static void __init init_irq_default_affinity(void) |
| -- |
| 1.7.10.4 |
| |