diff options
| author | Pavankumar Kondeti <pkondeti@codeaurora.org> | 2017-06-16 09:36:25 +0530 |
|---|---|---|
| committer | Pavankumar Kondeti <pkondeti@codeaurora.org> | 2017-06-30 10:41:00 +0530 |
| commit | 971af7d6edebc1ba813b7a1248bc4f1d6d763c97 (patch) | |
| tree | d9f4af6446672dd7c8a2f30f4ec8bf23f405fc2a | |
| parent | cd6d19b8e42cfef81a1ee3c4e4367295e8025024 (diff) | |
genirq: honour default IRQ affinity setting during migration
Userspace can set the default IRQ affinity setting by writing into
/proc/irq/default_smp_affinity file. When an IRQ affinity is
broken during isolation/hotplug,override the affinity to online and
un-isolated CPUs from the default affinity CPUs. If no such CPU
is available, then only override with cpu_online_mask.
Change-Id: I7578728ed0d7c17c5890d9916cfd6451d1968568
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
| -rw-r--r-- | kernel/irq/cpuhotplug.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c index 3dc1dbd9c166..4684b7595e63 100644 --- a/kernel/irq/cpuhotplug.c +++ b/kernel/irq/cpuhotplug.c @@ -36,10 +36,21 @@ static bool migrate_one_irq(struct irq_desc *desc) affinity = &available_cpus; if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) { + /* + * The order of preference for selecting a fallback CPU is + * + * (1) online and un-isolated CPU from default affinity + * (2) online and un-isolated CPU + * (3) online CPU + */ cpumask_andnot(&available_cpus, cpu_online_mask, cpu_isolated_mask); - if (cpumask_empty(affinity)) + if (cpumask_intersects(&available_cpus, irq_default_affinity)) + cpumask_and(&available_cpus, &available_cpus, + irq_default_affinity); + else if (cpumask_empty(&available_cpus)) affinity = cpu_online_mask; + /* * We are overriding the affinity with all online and * un-isolated cpus. irq_set_affinity_locked() call |