Now that mips/OCTEON support has been merged, this patch set has
slightly more urgency.
The interrupt affinity on OCTEON is determined by irq_default_affinity,
because that is what the code in kernel/irq/manage.c uses to set
affinity. Since for the majority of devices (Serial, Compact Flash,
Network...) we want interrupts to be handled on a single CPU, we set
irq_default_affinity to the boot CPU in init_IRQ(). The problem we
have is that with the new cpumask infrastructure, irq_default_affinity
is being initialized in core_initcall which undoes our initialization.
As I said in 2/2:
Move the initialization of irq_default_affinity to early_irq_init
as core_initcall is too late.
irq_default_affinity can be used in init_IRQ and potentially timer
and SMP init as well. All of these happen before core_initcall.
Moving the initialization to early_irq_init ensures that it is
initialized before it is used.
Mike Travis pointed out that irq_default_affinity depends on
CONFIG_GENERIC_HARDIRQS in addition to CONFIG_SMP. So to make things
consistent, I added 1/2 so that the irq_*_affinity functions and
irq_default_affinity are defined for the same conditions that they are
I Took Linus' suggestion to move init_irq_default_affinity over to
kernel/irq/handle.c, however due to the way that cpumask_*() are
defined, it is still necessary to have the ugly ifdefs, but now they
are localized to init_irq_default_affinity.
Mike Travis also suggested that alloc_bootmem_cpumask_var() be used in
preference to alloc_cpumask_var, so I incorporated that suggestion as
I tested both with and without CONFIG_SMP, on mips/cavium_octeon, Mike
tested a similar(but not identical patch) on x86_64.
Changes from v2 of this set are just a small rearrangement of the
#ifdefs suggested by Ihar Hrachyshka that make the code look a bit
I will reply with the two patches.
David Daney (2):
Make irq_*_affinity depend on CONFIG_GENERIC_HARDIRQS too.
cpumask fallout: Initialize irq_default_affinity earlier (v3).
kernel/irq/handle.c | 16 ++++++++++++++++
kernel/irq/manage.c | 10 +---------
2 files changed, 17 insertions(+), 9 deletions(-)