diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-05-25 16:59:47 +0200 |
|---|---|---|
| committer | Viresh Kumar <viresh.kumar@linaro.org> | 2013-03-12 14:56:33 +0530 |
| commit | 430219a653ec0e8bc2297db1a3402913bc2073b2 (patch) | |
| tree | 23d1a751f1ebd9aeecad4d1fb116f7e5c07c789d | |
| parent | f6161aa153581da4a3867a2d1a7caf4be19b6ec9 (diff) | |
| download | vexpress-lsk-430219a653ec0e8bc2297db1a3402913bc2073b2.tar.gz | |
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>
| -rw-r--r-- | Documentation/kernel-parameters.txt | 9 | ||||
| -rw-r--r-- | 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 4609e81dbc3..32d3c0da4c8 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1189,6 +1189,15 @@ 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 192a302d6cf..473b2b6eccb 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) |