[PATCH v2 0/3] Support managed interrupts for platform devices

From: John Garry
Date: Wed Oct 28 2020 - 21:21:34 EST


So far, managed interrupts are only used for PCI MSIs. This series add
platform device support for managed interrupts. Initially this topic was
discussed at [0].

The method to enable managed interrupts is to allocate all the IRQs for
the device, and then switch the interrupts to managed - this is done
through new function irq_update_affinity_desc().

API platform_get_irqs_affinity() is added as a helper to manage this work,
such that we don't need to export irq_update_affinity_desc() or
irq_create_affinity_masks().

For now, the HiSilicon SAS v2 hw driver is switched over. This is used
in the D05 dev board.

Performance gain observed for 6x SAS SSDs is ~357K -> 420K IOPs for fio read.

[0] https://lore.kernel.org/lkml/84a9411b-4ae3-1928-3d35-1666f2687ec8@xxxxxxxxxx/

Changes since v1:
- Update authorship on genirq change

John Garry (3):
genirq/affinity: Add irq_update_affinity_desc()
Driver core: platform: Add platform_get_irqs_affinity()
scsi: hisi_sas: Expose HW queues for v2 hw

drivers/base/platform.c | 58 +++++++++++++++++++++
drivers/scsi/hisi_sas/hisi_sas.h | 4 ++
drivers/scsi/hisi_sas/hisi_sas_main.c | 11 ++++
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 71 ++++++++++++++++++++++----
include/linux/interrupt.h | 8 +++
include/linux/platform_device.h | 5 ++
kernel/irq/manage.c | 19 +++++++
7 files changed, 165 insertions(+), 11 deletions(-)

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2.26.2