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Date:   Fri, 23 Dec 2022 08:35:43 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Keith Busch <kbusch@meta.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Matthew Wilcox <willy@infradead.org>,
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        Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCHv2 08/11] dmapool: consolidate page initialization
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References: <20221216201625.2362737-1-kbusch@meta.com>
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> +	page->in_use = 0;
> +	page->offset = 0;

This move makes total sense to me.

>  		return NULL;
>  
>  	spin_lock_irqsave(&pool->lock, flags);
> -
> -	list_add(&page->page_list, &pool->page_list);
> +	pool_initialise_page(pool, page);

.. but this now moves all of pool_initialise_page inside the
pool->lock critical section.  Is that really a good idea?