On Wed, 6 May 2015, Jiang Liu wrote: > Hi Thomas, > This is the simplified version, which removed the kernel parameter. > Seems much simpler:) But it can be made even simpler. :) > +enum { > + /* Allocate CPU vectors from CPUs on device local node */ > + X86_VECTOR_POL_NODE = 0x1, > + /* Allocate CPU vectors from all online CPUs */ > + X86_VECTOR_POL_GLOBAL = 0x2, > + /* Allocate CPU vectors from caller specified CPUs */ > + X86_VECTOR_POL_CALLER = 0x4, > + X86_VECTOR_POL_MIN = X86_VECTOR_POL_NODE, > + X86_VECTOR_POL_MAX = X86_VECTOR_POL_CALLER, > +}; > +static int assign_irq_vector_policy(int irq, int node, > + struct apic_chip_data *data, > + struct irq_alloc_info *info) > +{ > + int err = -EBUSY; > + unsigned int policy; > + const struct cpumask *mask; > + > + if (info && info->mask) > + policy = X86_VECTOR_POL_CALLER; > + else > + policy = X86_VECTOR_POL_MIN; > + > + for (; policy <= X86_VECTOR_POL_MAX; policy <<= 1) { > + switch (policy) { > + case X86_VECTOR_POL_NODE: > + if (node >= 0) > + mask = cpumask_of_node(node); > + else > + mask = NULL; > + break; > + case X86_VECTOR_POL_GLOBAL: > + mask = apic->target_cpus(); > + break; > + case X86_VECTOR_POL_CALLER: > + if (info && info->mask) > + mask = info->mask; > + else > + mask = NULL; > + break; > + default: > + mask = NULL; > + break; > + } > + if (mask) { > + err = assign_irq_vector(irq, data, mask); > + if (!err) > + return 0; > + } > + } This looks pretty overengineered now that you don't have that parameter check. if (info && info->mask) return assign_irq_vector(irq, data, info->mask); if (node >= 0) { err = assign_irq_vector(irq, data, cpumask_of_node(node)); if (!err) return 0; } return assign_irq_vector(irq, data, apic->target_cpus()); Should do the same, right? Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html