From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Waiman Long <longman@redhat.com>
Cc: Aaron Tomlin <atomlin@atomlin.com>,
axboe@kernel.dk, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me,
mst@redhat.com, aacraid@microsemi.com,
James.Bottomley@hansenpartnership.com,
martin.petersen@oracle.com, liyihang9@h-partners.com,
kashyap.desai@broadcom.com, sumit.saxena@broadcom.com,
shivasharan.srikanteshwara@broadcom.com,
chandrakanth.patil@broadcom.com, sathya.prakash@broadcom.com,
sreekanth.reddy@broadcom.com,
suganath-prabu.subramani@broadcom.com, ranjan.kumar@broadcom.com,
jinpu.wang@cloud.ionos.com, tglx@kernel.org, mingo@redhat.com,
peterz@infradead.org, juri.lelli@redhat.com,
vincent.guittot@linaro.org, akpm@linux-foundation.org,
maz@kernel.org, ruanjinjie@huawei.com, yphbchou0911@gmail.com,
wagi@kernel.org, frederic@kernel.org, chenridong@huawei.com,
hare@suse.de, kch@nvidia.com, ming.lei@redhat.com,
steve@abita.co, sean@ashe.io, chjohnst@gmail.com, neelx@suse.com,
mproche@gmail.com, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org, virtualization@lists.linux.dev,
linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org,
megaraidlinux.pdl@broadcom.com, mpi3mr-linuxdrv.pdl@broadcom.com,
MPT-FusionLinux.pdl@broadcom.com
Subject: Re: [PATCH v9 09/13] isolation: Introduce io_queue isolcpus type
Date: Thu, 2 Apr 2026 09:58:10 +0200 [thread overview]
Message-ID: <20260402075810.w0GVbX0Z@linutronix.de> (raw)
In-Reply-To: <5e6aa61e-0ad0-4027-bba9-cd906ab0d7e8@redhat.com>
On 2026-04-01 15:05:21 [-0400], Waiman Long wrote:
> > Could we please clarify whether we want to keep it and this
> > additionally or if managed_irq could be used instead. This adds another
> > bit. If networking folks jump in on managed_irqs, would they need to
> > duplicate this with their net sub flag?
>
> Yes, I will very much prefer to reuse an existing HK cpumask like
> managed_irqs for this purpose, if possible, rather than adding another
> cpumask that we need to manage. Note that we are in the process of making
> these housekeeping cpumasks modifiable at run time in the near future.
Now if you want to change it at run time, it would mean to reconfigure
the interrupts, device and so on. Not sure if this useful _or_ if it
would be "easier" to just the tell upper layer (block in case of I/O)
not to perform any request on this CPU. Then we would have an interrupt
on that CPU but it wouldn't do anything.
It would only become a problem if you would have less queues than CPUs
and you would like to migrate things.
> Cheers,
> Longman
Sebastian
next prev parent reply other threads:[~2026-04-02 7:58 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-30 22:10 [PATCH v9 00/13] blk: honor isolcpus configuration Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 01/13] scsi: aacraid: use block layer helpers to calculate num of queues Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 02/13] lib/group_cpus: remove dead !SMP code Aaron Tomlin
2026-04-01 12:29 ` Sebastian Andrzej Siewior
2026-04-01 19:31 ` Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 03/13] lib/group_cpus: Add group_mask_cpus_evenly() Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 04/13] genirq/affinity: Add cpumask to struct irq_affinity Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 05/13] blk-mq: add blk_mq_{online|possible}_queue_affinity Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 06/13] nvme-pci: use block layer helpers to constrain queue affinity Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 07/13] scsi: Use " Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 08/13] virtio: blk/scsi: use " Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 09/13] isolation: Introduce io_queue isolcpus type Aaron Tomlin
2026-04-01 12:49 ` Sebastian Andrzej Siewior
2026-04-01 19:05 ` Waiman Long
2026-04-02 7:58 ` Sebastian Andrzej Siewior [this message]
2026-04-03 1:54 ` Waiman Long
2026-04-01 20:58 ` Aaron Tomlin
2026-04-02 9:09 ` Sebastian Andrzej Siewior
2026-04-03 0:50 ` Aaron Tomlin
2026-04-03 1:20 ` Ming Lei
2026-03-30 22:10 ` [PATCH v9 10/13] blk-mq: use hk cpus only when isolcpus=io_queue is enabled Aaron Tomlin
2026-03-31 23:05 ` Keith Busch
2026-04-01 17:16 ` Aaron Tomlin
2026-04-03 1:43 ` Ming Lei
2026-03-30 22:10 ` [PATCH v9 11/13] blk-mq: prevent offlining hk CPUs with associated online isolated CPUs Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 12/13] genirq/affinity: Restrict managed IRQ affinity to housekeeping CPUs Aaron Tomlin
2026-03-30 22:10 ` [PATCH v9 13/13] docs: add io_queue flag to isolcpus Aaron Tomlin
2026-03-31 1:01 ` [PATCH v9 00/13] blk: honor isolcpus configuration Ming Lei
2026-03-31 13:38 ` Aaron Tomlin
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=20260402075810.w0GVbX0Z@linutronix.de \
--to=bigeasy@linutronix.de \
--cc=James.Bottomley@hansenpartnership.com \
--cc=MPT-FusionLinux.pdl@broadcom.com \
--cc=aacraid@microsemi.com \
--cc=akpm@linux-foundation.org \
--cc=atomlin@atomlin.com \
--cc=axboe@kernel.dk \
--cc=chandrakanth.patil@broadcom.com \
--cc=chenridong@huawei.com \
--cc=chjohnst@gmail.com \
--cc=frederic@kernel.org \
--cc=hare@suse.de \
--cc=hch@lst.de \
--cc=jinpu.wang@cloud.ionos.com \
--cc=juri.lelli@redhat.com \
--cc=kashyap.desai@broadcom.com \
--cc=kbusch@kernel.org \
--cc=kch@nvidia.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=linux-scsi@vger.kernel.org \
--cc=liyihang9@h-partners.com \
--cc=longman@redhat.com \
--cc=martin.petersen@oracle.com \
--cc=maz@kernel.org \
--cc=megaraidlinux.pdl@broadcom.com \
--cc=ming.lei@redhat.com \
--cc=mingo@redhat.com \
--cc=mpi3mr-linuxdrv.pdl@broadcom.com \
--cc=mproche@gmail.com \
--cc=mst@redhat.com \
--cc=neelx@suse.com \
--cc=peterz@infradead.org \
--cc=ranjan.kumar@broadcom.com \
--cc=ruanjinjie@huawei.com \
--cc=sagi@grimberg.me \
--cc=sathya.prakash@broadcom.com \
--cc=sean@ashe.io \
--cc=shivasharan.srikanteshwara@broadcom.com \
--cc=sreekanth.reddy@broadcom.com \
--cc=steve@abita.co \
--cc=suganath-prabu.subramani@broadcom.com \
--cc=sumit.saxena@broadcom.com \
--cc=tglx@kernel.org \
--cc=vincent.guittot@linaro.org \
--cc=virtualization@lists.linux.dev \
--cc=wagi@kernel.org \
--cc=yphbchou0911@gmail.com \
/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