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Message-ID: <143ec153-fe71-7a03-a10a-589ecd63eb71@huaweicloud.com>
Date: Tue, 28 May 2024 10:06:16 +0800
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Subject: Re: [PATCH] md: make md_flush_request() more readable
To: Christoph Hellwig <hch@infradead.org>
Cc: song@kernel.org, linux-raid@vger.kernel.org,
 linux-kernel@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com,
 houtao1@huawei.com, yangerkun@huawei.com
References: <20240525185622.3896616-1-linan666@huaweicloud.com>
 <ZlL4rxKqcV5ePLXu@infradead.org>
From: Li Nan <linan666@huaweicloud.com>
In-Reply-To: <ZlL4rxKqcV5ePLXu@infradead.org>
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在 2024/5/26 16:54, Christoph Hellwig 写道:
> On Sun, May 26, 2024 at 02:56:22AM +0800, linan666@huaweicloud.com wrote:
>> -		bio = NULL;
>> -	}
>> -	spin_unlock_irq(&mddev->lock);
>> -
>> -	if (!bio) {
>> +		spin_unlock_irq(&mddev->lock);
>>   		INIT_WORK(&mddev->flush_work, submit_flushes);
>>   		queue_work(md_wq, &mddev->flush_work);
>>   	} else {
>>   		/* flush was performed for some other bio while we waited. */
>> +		spin_unlock_irq(&mddev->lock);
>>   		if (bio->bi_iter.bi_size == 0)
>>   			/* an empty barrier - all done */
> 
> This stil looks like a somwwhat odd flow  Why not go all the way
> and turn it into:
> 
> 
> 	...
> 		queue_work(md_wq, &mddev->flush_work);
> 		return true;
> 	}
> 
> 	/* flush was performed for some other bio while we waited. */
> 	spin_unlock_irq(&mddev->lock);
> 	if (bio->bi_iter.bi_size == 0) {
> 		/* pure flush without data - all done */
> 		bio_endio(bio);
> 		return true;
> 	}
> 	bio->bi_opf &= ~REQ_PREFLUSH;
> 	return false;
> }

Yeah, it looks better. I will changed it in v2.

Thansk for your suggestion.

-- 
Thanks,
Nan