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Date:   Wed, 11 Jan 2023 10:06:31 +0000
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Subject: Re: [PATCH V4 0/6] genirq/affinity: Abstract APIs from managed irq
 affinity spread
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To:     Ming Lei <ming.lei@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Jens Axboe <axboe@kernel.dk>
Cc:     linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>
References: <20221227022905.352674-1-ming.lei@redhat.com>
From:   John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
In-Reply-To: <20221227022905.352674-1-ming.lei@redhat.com>
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On 27/12/2022 02:28, Ming Lei wrote:
> irq_build_affinity_masks() actually grouping CPUs evenly into each managed
> irq vector according to NUMA and CPU locality, and it is reasonable to abstract
> one generic API for grouping CPUs evenly, the idea is suggested by Thomas
> Gleixner.
> 
> group_cpus_evenly() is abstracted and put into lib/, so blk-mq can re-use
> it to build default queue mapping.
> 
> blk-mq IO perf data is observed as more stable, meantime with big
> improvement, see detailed data in the last patch.
> 
> Please consider it for v6.3!

Just wondering could this be a better alternative for some drivers than 
using cpumask_local_spread()?

Thanks,
John