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Date: Mon, 20 May 2024 17:37:42 +0200
From: Christoph Hellwig <hch@lst.de>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Keith Busch <kbusch@kernel.org>, Ming Lei <ming.lei@redhat.com>,
	Christoph Hellwig <hch@lst.de>, Keith Busch <kbusch@meta.com>,
	linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] nvme-pci: allow unmanaged interrupts
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References: <20240510141459.3207725-1-kbusch@meta.com> <20240510141459.3207725-2-kbusch@meta.com> <20240510151047.GA10486@lst.de> <Zj5JMqWRY187PqnD@kbusch-mbp.dhcp.thefacebook.com> <Zj6yvTxIpUnOXl7R@fedora> <Zj6-1sXvUNZWO1pB@kbusch-mbp.dhcp.thefacebook.com> <87r0e7mt9w.ffs@tglx>
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On Sun, May 12, 2024 at 08:35:55AM +0200, Thomas Gleixner wrote:
> That's expected as you pin the I/O operation on the isolated CPUs which
> in turn makes them use the per CPU queue.
> 
> The isolated CPUs are only excluded for device management interrupts,
> but not for the affinity spread of the queues.

We'll probably need a version of isolcpus that also excludes the
interrupt spread given that users are asking for it.  And I'd much
prefer that over adding radom module options to every driver to disable
managed interrupts.