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Subject: Re: [PATCH 1/1] md/raid10: Remove rcu_dereference when it doesn't
 need rcu lock to protect
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To:     Xiao Ni <xni@redhat.com>, linux-raid@vger.kernel.org
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From:   Guoqing Jiang <guoqing.jiang@linux.dev>
Message-ID: <4398469c-571e-ae00-99df-6e46d2edb3a7@linux.dev>
Date:   Mon, 16 Aug 2021 17:33:00 +0800
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Hi Xiao,

On 8/16/21 5:01 PM, Xiao Ni wrote:
> On Mon, Aug 16, 2021 at 2:36 PM Guoqing Jiang <guoqing.jiang@linux.dev> wrote:
>> Can rdev be removed between the first loop and the second loop?
>>
> Hi Guoqing
>
> As the patch's commit message says, it adds rdev->nr_pending already.
> So we can guarantee the rdev
> can't be removed during the first loop and the second loop.

I missed that, thanks for clarification. Maybe mention it in description 
that  nr_pending is incremented
which means rdev can't disappear.

Thanks,
Guoqing