[RFC PATCH v5 2/4] genirq: add irq_migrate_all_off_this_cpu() for cpu hotplug

[Thomas Gleixner]

On Sat, 19 Sep 2015, Yang Yingliang wrote:

> Add irq_migrate_all_off_this_cpu() into kernel/irq/migration.c.

This doesn't make any sense at all. 

You just reuse the existing file to stick your new code into it
without reusing a single bit in that file. Aside of that it's
unconditionally compiled, which means all existing users of
CONFIG_GENERIC_PENDING_IRQ are burdened with pointless code.

The right thing to do is:

Add that code to a new file: kernel/irq/cpuhotplug.c and make that
depend on CONFIG_GENERIC_IRQ_MIGRATION.

Thanks,

	tglx