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Date: Wed, 18 Dec 2024 17:23:21 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Caleb Sander <csander@purestorage.com>
Cc: David Miller <davem@davemloft.net>, Tom Herbert <therbert@google.com>,
 Thomas Gleixner <tglx@linutronix.de>, Eli Cohen <elic@nvidia.com>, Ben
 Hutchings <ben@decadent.org.uk>, Eric Dumazet <edumazet@google.com>, Paolo
 Abeni <pabeni@redhat.com>, netdev@vger.kernel.org, Linux Kernel Mailing
 List <linux-kernel@vger.kernel.org>
Subject: Re: cpu_rmap maps CPUs to wrong interrupts after reprogramming
 affinities
Message-ID: <20241218172321.71ea4b4a@kernel.org>
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On Fri, 13 Dec 2024 10:18:30 -0800 Caleb Sander wrote:
> I can see a few possible ways to address this:
> - Store the current affinity masks for all the IRQs in struct cpu_rmap
> so the next closest IRQ can be computed when a CPU's closest IRQ is
> invalidated. This would significantly increase the size of struct
> cpu_rmap.

Ahmed is actively working on something along those lines:
https://lore.kernel.org/all/20241218165843.744647-1-ahmed.zaki@intel.com/
hopefully we can leverage it?