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Subject: Re: [PATCH 0/2] small optimization for accessing queue map
To:     Jianchao Wang <jianchao.w.wang@oracle.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1548325533-1695-1-git-send-email-jianchao.w.wang@oracle.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <531e1343-a941-0137-e21c-036ca8dfbd5a@kernel.dk>
Date:   Thu, 24 Jan 2019 11:08:12 -0700
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On 1/24/19 3:25 AM, Jianchao Wang wrote:
> Hi Jens
> 
> These two patches are small optimization for accessing the queue mapping
> in hot path. It saves the queue mapping results into blk_mq_ctx directly,
> then we needn't do the complicated bounce on queue_hw_ctx[] map[] and
> mq_map[].

I like this a lot, the current double indirect does suck, and it does show
up in profiles as well. I'll run some testing with this, thanks!

-- 
Jens Axboe