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Subject: Re: [dm-devel] [PATCH -next v2 2/6] md: refactor action_store() for
 'idle' and 'frozen'
To:     Xiao Ni <xni@redhat.com>, Yu Kuai <yukuai1@huaweicloud.com>,
        guoqing.jiang@linux.dev, agk@redhat.com, snitzer@kernel.org,
        dm-devel@redhat.com, song@kernel.org
Cc:     yi.zhang@huawei.com, yangerkun@huawei.com,
        linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
        "yukuai (C)" <yukuai3@huawei.com>
References: <20230529132037.2124527-1-yukuai1@huaweicloud.com>
 <20230529132037.2124527-3-yukuai1@huaweicloud.com>
 <b780ccfd-66b1-fdd1-b33e-aa680fbd86f1@redhat.com>
From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <1aaf9150-bbd3-87a8-8d54-8b5d63ab5ed3@huaweicloud.com>
Date:   Tue, 13 Jun 2023 20:00:10 +0800
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Hi,

在 2023/06/13 16:02, Xiao Ni 写道:
> 
> 在 2023/5/29 下午9:20, Yu Kuai 写道:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> Prepare to handle 'idle' and 'frozen' differently to fix a deadlock, 
>> there
>> are no functional changes except that MD_RECOVERY_RUNNING is checked
>> again after 'reconfig_mutex' is held.
> 
> 
> Can you explain more about why it needs to check MD_RECOVERY_RUNNING 
> again here?

As I explain in the following comment:
>> +    /*
>> +     * Check again in case MD_RECOVERY_RUNNING is cleared before lock is
>> +     * held.
>> +     */
>> +    if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
>> +        mddev_unlock(mddev);
>> +        return;
>> +    }

Thanks,
Kuai