extern int
irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
-struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs);
struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, int nvec);
int irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec);
return 0;
}
-static inline struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs)
-{
- *nr_vecs = 1;
- return NULL;
-}
-
static inline struct cpumask *
irq_create_affinity_masks(const struct cpumask *affinity, int nvec)
{
put_online_cpus();
return ret;
}
-
-static int get_first_sibling(unsigned int cpu)
-{
- unsigned int ret;
-
- ret = cpumask_first(topology_sibling_cpumask(cpu));
- if (ret < nr_cpu_ids)
- return ret;
- return cpu;
-}
-
-/*
- * Take a map of online CPUs and the number of available interrupt vectors
- * and generate an output cpumask suitable for spreading MSI/MSI-X vectors
- * so that they are distributed as good as possible around the CPUs. If
- * more vectors than CPUs are available we'll map one to each CPU,
- * otherwise we map one to the first sibling of each socket.
- *
- * If there are more vectors than CPUs we will still only have one bit
- * set per CPU, but interrupt code will keep on assigning the vectors from
- * the start of the bitmap until we run out of vectors.
- */
-struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs)
-{
- struct cpumask *affinity_mask;
- unsigned int max_vecs = *nr_vecs;
-
- if (max_vecs == 1)
- return NULL;
-
- affinity_mask = kzalloc(cpumask_size(), GFP_KERNEL);
- if (!affinity_mask) {
- *nr_vecs = 1;
- return NULL;
- }
-
- get_online_cpus();
- if (max_vecs >= num_online_cpus()) {
- cpumask_copy(affinity_mask, cpu_online_mask);
- *nr_vecs = num_online_cpus();
- } else {
- unsigned int vecs = 0, cpu;
-
- for_each_online_cpu(cpu) {
- if (cpu == get_first_sibling(cpu)) {
- cpumask_set_cpu(cpu, affinity_mask);
- vecs++;
- }
-
- if (--max_vecs == 0)
- break;
- }
- *nr_vecs = vecs;
- }
- put_online_cpus();
-
- return affinity_mask;
-}