From: John Garry <john.garry@huawei.com>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: <jejb@linux.ibm.com>, <martin.petersen@oracle.com>,
<lenb@kernel.org>, <rjw@rjwysocki.net>, <tglx@linutronix.de>,
<maz@kernel.org>, <linux-scsi@vger.kernel.org>,
<linux-kernel@vger.kernel.org>, <linuxarm@huawei.com>,
<linux-acpi@vger.kernel.org>, <dwagner@suse.de>
Subject: Re: [PATCH v5 4/5] Driver core: platform: Add devm_platform_get_irqs_affinity()
Date: Wed, 9 Dec 2020 19:36:52 +0000 [thread overview]
Message-ID: <0fa6487e-d225-dde6-f23f-f955d87ee706@huawei.com> (raw)
In-Reply-To: <X9Ehy28876ezAOLH@kroah.com>
On 09/12/2020 19:13, Greg KH wrote:
Hi Greg,
>> For this HW version, the device is on the system bus, directly addressable
>> by the CPU.
> What do you mean by "system bus"?
Maybe my terminology is wrong, the point is that we have a platform
device driver.
>
>> Motivation is that I wanted to switch the HW completion queues to use
>> managed interrupts.
> Fair enough, seems like overkill for a "platform" bus though:)
>
>>> What in-kernel driver needs this complexity? I can't take new apis
>>> without a real user in the tree, sorry.
>> It's in the final patch in the serieshttps://lore.kernel.org/linux-scsi/1606905417-183214-1-git-send-email-john.garry@huawei.com/T/#m0df7e7cd6f0819b99aaeb6b7f8939ef1e17b8a83.
> Ah, I missed that, I thought that was some high-speed scsi thing, not a
> tiny platform driver...
It is actually is a high-speed SCSI thing also, SAS 3.0 :)
>
>> I don't anticipate a huge number of users of this API in future, as most
>> multi-queue devices are PCI devices; so we could do the work of this API in
>> the driver itself, but the preference was not to export genirq functions
>> like irq_update_affinity_desc() or irq_create_affinity_masks(), and rather
>> have a common helper in the core platform code.
> Ok, I'd like to have the irq maintainers/developers ack this before
> taking it in the driver core, as someone is going to have to maintain
> this crazy thing for forever if it gets merged.
>
irq experts are cc'ed and have been very helpful here
So the API mushroomed a bit over time, as I realized that we need to
support tearing down the irq mapping, make as devm method, use
irq_calc_affinity_vectors(). Not sure how we could factor any of it out
to become less of your problem.
Thanks,
John
next prev parent reply other threads:[~2020-12-09 19:38 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-02 10:36 [PATCH v5 0/5] Support managed interrupts for platform devices John Garry
2020-12-02 10:36 ` [PATCH v5 1/5] genirq/affinity: Add irq_update_affinity_desc() John Garry
2020-12-02 10:36 ` [PATCH v5 2/5] resource: Add irqresource_disabled() John Garry
2020-12-02 10:36 ` [PATCH v5 3/5] ACPI: Drop acpi_dev_irqresource_disabled() John Garry
2020-12-02 10:36 ` [PATCH v5 4/5] Driver core: platform: Add devm_platform_get_irqs_affinity() John Garry
2020-12-09 18:32 ` Greg KH
2020-12-09 19:04 ` John Garry
2020-12-09 19:13 ` Greg KH
2020-12-09 19:36 ` John Garry [this message]
2020-12-09 19:39 ` Marc Zyngier
2020-12-10 10:10 ` John Garry
2020-12-10 15:29 ` Greg KH
2020-12-10 16:37 ` John Garry
2020-12-02 10:36 ` [PATCH v5 5/5] scsi: hisi_sas: Expose HW queues for v2 hw John Garry
2020-12-11 16:56 ` John Garry
2020-12-11 17:20 ` Martin K. Petersen
2020-12-11 17:33 ` John Garry
2020-12-11 15:01 ` [PATCH v5 0/5] Support managed interrupts for platform devices Marc Zyngier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0fa6487e-d225-dde6-f23f-f955d87ee706@huawei.com \
--to=john.garry@huawei.com \
--cc=dwagner@suse.de \
--cc=gregkh@linuxfoundation.org \
--cc=jejb@linux.ibm.com \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=linuxarm@huawei.com \
--cc=martin.petersen@oracle.com \
--cc=maz@kernel.org \
--cc=rjw@rjwysocki.net \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).