linux/kernel/irq
Dou Liyang c410abbbac genirq/affinity: Add is_managed to struct irq_affinity_desc
Devices which use managed interrupts usually have two classes of
interrupts:

  - Interrupts for multiple device queues
  - Interrupts for general device management

Currently both classes are treated the same way, i.e. as managed
interrupts. The general interrupts get the default affinity mask assigned
while the device queue interrupts are spread out over the possible CPUs.

Treating the general interrupts as managed is both a limitation and under
certain circumstances a bug. Assume the following situation:

 default_irq_affinity = 4..7

So if CPUs 4-7 are offlined, then the core code will shut down the device
management interrupts because the last CPU in their affinity mask went
offline.

It's also a limitation because it's desired to allow manual placement of
the general device interrupts for various reasons. If they are marked
managed then the interrupt affinity setting from both user and kernel space
is disabled. That limitation was reported by Kashyap and Sumit.

Expand struct irq_affinity_desc with a new bit 'is_managed' which is set
for truly managed interrupts (queue interrupts) and cleared for the general
device interrupts.

[ tglx: Simplify code and massage changelog ]

Reported-by: Kashyap Desai <kashyap.desai@broadcom.com>
Reported-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Dou Liyang <douliyangs@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Cc: shivasharan.srikanteshwara@broadcom.com
Cc: ming.lei@redhat.com
Cc: hch@lst.de
Cc: bhelgaas@google.com
Cc: douliyang1@huawei.com
Link: https://lkml.kernel.org/r/20181204155122.6327-3-douliyangs@gmail.com
2018-12-19 11:32:08 +01:00
..
affinity.c genirq/affinity: Add is_managed to struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
autoprobe.c genirq: Cleanup top of file comments 2018-03-20 14:23:27 +01:00
chip.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
cpuhotplug.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
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 genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debug 2018-06-22 14:22:00 +02:00
devres.c genirq/core: Introduce struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
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 genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
internals.h genirq: Make legacy autoprobing work again 2018-02-01 11:09:40 +01:00
ipi.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
irq_sim.c irq/irq_sim: Store multiple interrupt offsets in a bitmap 2018-12-13 09:35:31 +00:00
irqdesc.c genirq/affinity: Add is_managed to struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
irqdomain.c genirq/core: Introduce struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
Kconfig genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete 2018-08-03 12:14:10 +02:00
Makefile Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:33:11 -08:00
manage.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
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 genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
timings.c genirq: Remove license boilerplate/references 2018-03-20 14:23:28 +01:00