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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-23 20:53:53 +08:00
linux-next/kernel/irq
Ming Lei b1a5a73e64 genirq/affinity: Spread vectors on node according to nr_cpu ratio
Now __irq_build_affinity_masks() spreads vectors evenly per node, but there
is a case that not all vectors have been spread when each numa node has a
different number of CPUs which triggers the warning in the spreading code.

Improve the spreading algorithm by

 - assigning vectors according to the ratio of the number of CPUs on a node
   to the number of remaining CPUs.

 - running the assignment from smaller nodes to bigger nodes to guarantee
   that every active node gets allocated at least one vector.

This ensures that all vectors are spread out. Asided of that the spread
becomes more fair if the nodes have different number of CPUs.

For example, on the following machine:
	CPU(s):              16
	On-line CPU(s) list: 0-15
	Thread(s) per core:  1
	Core(s) per socket:  8
	Socket(s):           2
	NUMA node(s):        2
	...
	NUMA node0 CPU(s):   0,1,3,5-9,11,13-15
	NUMA node1 CPU(s):   2,4,10,12

When a driver requests to allocate 8 vectors, the following spread results:

	irq 31, cpu list 2,4
	irq 32, cpu list 10,12
	irq 33, cpu list 0-1
	irq 34, cpu list 3,5
	irq 35, cpu list 6-7
	irq 36, cpu list 8-9
	irq 37, cpu list 11,13
	irq 38, cpu list 14-15

So Node 0 has now 6 and Node 1 has 2 vectors assigned. The original
algorithm assigned 4 vectors on each node which was unfair versus Node 0.

[ tglx: Massaged changelog ]

Reported-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
Link: https://lkml.kernel.org/r/20190816022849.14075-3-ming.lei@redhat.com
2019-08-27 16:31:17 +02:00
..
affinity.c genirq/affinity: Spread vectors on node according to nr_cpu ratio 2019-08-27 16:31:17 +02:00
autoprobe.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
chip.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 11:22:57 -07:00
cpuhotplug.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
debug.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2018-02-01 13:36:15 -08:00
debugfs.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
devres.c genirq/devres: Use struct_size() in devm_kzalloc() 2019-04-16 21:54:03 +02:00
dummychip.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
generic-chip.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
handle.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
internals.h Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 11:22:57 -07:00
ipi.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
irq_sim.c irq/irq_sim: add irq_set_type() callback 2019-02-19 17:42:28 +01:00
irqdesc.c Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 11:01:13 -07:00
irqdomain.c irq/irqdomain: Fix comment typo 2019-07-06 10:40:20 +02:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile genirq/timings: Add selftest for circular array 2019-06-12 10:47:04 +02:00
manage.c genirq: Force interrupt threading on RT 2019-08-19 15:45:48 +02:00
matrix.c genirq/matrix: Improve target CPU selection for managed interrupts. 2018-11-06 23:20:13 +01:00
migration.c genirq/migration: Avoid out of line call if pending is not set 2018-06-06 15:18:20 +02:00
msi.c genirq/core: Introduce struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
pm.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
proc.c genirq: Speedup show_interrupts() 2018-06-22 14:22:58 +02:00
resend.c genirq: Cleanup top of file comments 2018-03-20 14:23:27 +01:00
settings.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spurious.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
timings.c genirq/timings: Add selftest for next event computation 2019-06-12 10:47:05 +02:00