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  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 18 Feb 2019 08:25:49 +0100 (CET)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Ming Lei <ming.lei@...hat.com>
cc:     LKML <linux-kernel@...r.kernel.org>,
        Christoph Hellwig <hch@....de>,
        Bjorn Helgaas <helgaas@...nel.org>,
        Jens Axboe <axboe@...nel.dk>, linux-block@...r.kernel.org,
        Sagi Grimberg <sagi@...mberg.me>,
        linux-nvme@...ts.infradead.org, linux-pci@...r.kernel.org,
        Keith Busch <keith.busch@...el.com>,
        Marc Zyngier <marc.zyngier@....com>,
        Sumit Saxena <sumit.saxena@...adcom.com>,
        Kashyap Desai <kashyap.desai@...adcom.com>,
        Shivasharan Srikanteshwara 
        <shivasharan.srikanteshwara@...adcom.com>
Subject: Re: [patch v6 7/7] genirq/affinity: Add support for non-managed
 affinity sets

Ming,

On Mon, 18 Feb 2019, Ming Lei wrote:
> On Sun, Feb 17, 2019 at 08:17:05PM +0100, Thomas Gleixner wrote:
> > I don't see how that would break blk-mq. The unmanaged set is not used by
> > the blk-mq stuff, that's some driver internal voodoo. So blk-mq still gets
> > a perfectly spread and managed interrupt set for the queues.
> 
> >From the discussion above, the use case is for megaraid_sas. And one of the
> two interrupt sets(managed and non-managed) will be chosen according to
> workloads runtime.
> 
> Each interrupt set actually defines one blk-mq queue mapping, and the
> queue mapping needs to respect the rule I mentioned now. However,
> non-managed affinity can be changed to any way anytime by user-space.
> 
> Recently HPSA tried to add one module parameter to use non-managed
> IRQ[1].
> 
> Also NVMe RDMA uses non-managed interrupts, and at least one CPU hotplug
> issue is never fixed yet[2]. 
> 
> [1] https://marc.info/?t=154387665200001&r=1&w=2
> [2] https://www.spinics.net/lists/linux-block/msg24140.html

Interesting. I misread the description which megasas folks provided
then. I'll drop that patch and get the other lot merged. Thanks for your
work and help with that!

Thanks,

	tglx

Powered by blists - more mailing lists