linux-kernel - [PATCH v3 0/5] Support managed interrupts for platform devices

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1606324841-217570-1-git-send-email-john.garry@huawei.com>
Date:   Thu, 26 Nov 2020 01:20:36 +0800
From:   John Garry <john.garry@...wei.com>
To:     <jejb@...ux.ibm.com>, <martin.petersen@...cle.com>,
        <lenb@...nel.org>, <rjw@...ysocki.net>,
        <gregkh@...uxfoundation.org>, <tglx@...utronix.de>
CC:     <linux-scsi@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linuxarm@...wei.com>, <linux-acpi@...r.kernel.org>,
        <maz@...nel.org>, "John Garry" <john.garry@...wei.com>
Subject: [PATCH v3 0/5] Support managed interrupts for platform devices

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

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

Function devm_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().

In the devm_platform_get_irqs_affinity() release call a new platform
method is used to "put" an irq. The reason for this is that per-irq
mapping (and irq_desc) needs to be recreated anew for re-probing the LLDD,
such that we don't attempt to reconfigure the managed or any other flag
for an irq_desc.

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@huawei.com/

Changes since v2:
- Update genirq change as follows:
 - Handle when the irq is started, active, or already managed
 - Reject update when CONFIG_GENERIC_IRQ_RESERVATION_MODE is set
- Revamp platform.c API as follows:
 - Make it devm type
 - Add platform_put_irq() and associated change in ACPI code to allow irq
   resource to be reset
 - Unmap irqs for driver removal
 - Change API to accept min and max vectors

John Garry (5):
  genirq/affinity: Add irq_update_affinity_desc()
  ACPI: Make acpi_dev_irqresource_disabled() public
  driver core: platform: Add platform_put_irq()
  Driver core: platform: Add devm_platform_get_irqs_affinity()
  scsi: hisi_sas: Expose HW queues for v2 hw

 drivers/acpi/resource.c                |   2 +-
 drivers/base/platform.c                | 126 +++++++++++++++++++++++++
 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 |  68 ++++++++++---
 include/linux/acpi.h                   |   5 +
 include/linux/interrupt.h              |   8 ++
 include/linux/platform_device.h        |   6 ++
 kernel/irq/manage.c                    |  63 +++++++++++++
 9 files changed, 279 insertions(+), 14 deletions(-)

-- 
2.26.2