alistair23-linux/arch/x86/kernel/apic
Suresh Siddha b39f25a849 x86/apic: Optimize cpu traversal in __assign_irq_vector() using domain membership
Currently __assign_irq_vector() goes through each cpu in the
specified mask until it finds a free vector in all the cpu's
that are part of the same interrupt domain. We visit all the
interrupt domain sibling cpus to reserve the free vector. So,
when we fail to find a free vector in an interrupt domain, it is
safe to continue our search with a cpu belonging to a new
interrupt domain. No need to go through each cpu, if the domain
containing that cpu is already visited.

Use the irq_cfg's old_domain to track the visited domains and
optimize the cpu traversal while finding a free vector in the
given cpumask.

NOTE: We can also optimize the search by using for_each_cpu() and
skip the current cpu, if it is not the first cpu in the mask
returned by the vector_allocation_domain(). But re-using the
cfg->old_domain to track the visited domains will be slightly
faster.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Link: http://lkml.kernel.org/r/1340656709-11423-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-06 11:00:21 +02:00
..
apic.c x86/apic: Fix ugly casting and branching in cpu_mask_to_apicid_and() 2012-06-14 12:53:14 +02:00
apic_flat_64.c x86/apic: Eliminate cpu_mask_to_apicid() operation 2012-06-14 12:53:13 +02:00
apic_noop.c x86/apic: Optimize cpu traversal in __assign_irq_vector() using domain membership 2012-07-06 11:00:21 +02:00
apic_numachip.c x86/apic: Eliminate cpu_mask_to_apicid() operation 2012-06-14 12:53:13 +02:00
bigsmp_32.c x86/apic: Eliminate cpu_mask_to_apicid() operation 2012-06-14 12:53:13 +02:00
es7000_32.c x86/apic/es7000: Make apicid of a cluster (not CPU) from a cpumask 2012-06-14 12:53:16 +02:00
hw_nmi.c x86, nmi: Wire up NMI handlers to new routines 2011-10-10 06:56:57 +02:00
io_apic.c x86/apic: Optimize cpu traversal in __assign_irq_vector() using domain membership 2012-07-06 11:00:21 +02:00
ipi.c x86: Always use x86_cpu_to_logical_apicid for cpu -> logical apic id 2011-01-28 14:54:05 +01:00
Makefile x86: Add NumaChip support 2011-12-05 17:17:24 +01:00
numaq_32.c x86/apic: Eliminate cpu_mask_to_apicid() operation 2012-06-14 12:53:13 +02:00
probe_32.c Merge branch 'x86/apic' into x86/platform 2012-06-18 11:09:49 +02:00
probe_64.c x86/platform: Introduce APIC post-initialization callback 2012-06-06 09:06:19 +02:00
summit_32.c x86/apic/es7000+summit: Always make valid apicid from a cpumask 2012-06-14 12:53:15 +02:00
x2apic_cluster.c x86/apic: Optimize cpu traversal in __assign_irq_vector() using domain membership 2012-07-06 11:00:21 +02:00
x2apic_phys.c x86/apic: Eliminate cpu_mask_to_apicid() operation 2012-06-14 12:53:13 +02:00
x2apic_uv_x.c x86/apic: Fix ugly casting and branching in cpu_mask_to_apicid_and() 2012-06-14 12:53:14 +02:00