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Date:   Tue, 29 Mar 2022 21:31:27 +0300
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Subject: Re: [PATCH 2/2] btrfs: Allocate page arrays using bulk page
 allocator.
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To:     Sweet Tea Dorminy <sweettea-kernel@dorminy.me>,
        Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>,
        Nick Terrell <terrelln@fb.com>, linux-kernel@vger.kernel.org,
        linux-btrfs@vger.kernel.org, kernel-team@fb.com
References: <cover.1648497027.git.sweettea-kernel@dorminy.me>
 <9cbd861d3b302e19b990848ea747d2ea91d01aed.1648497027.git.sweettea-kernel@dorminy.me>
From:   Nikolay Borisov <nborisov@suse.com>
In-Reply-To: <9cbd861d3b302e19b990848ea747d2ea91d01aed.1648497027.git.sweettea-kernel@dorminy.me>
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Precedence: bulk


On 28.03.22 г. 23:14 ч., Sweet Tea Dorminy wrote:
> While calling alloc_page() in a loop is an effective way to populate an
> array of pages, the kernel provides a method to allocate pages in bulk.
> alloc_pages_bulk_array() populates the NULL slots in a page array, trying to
> grab more than one page at a time.
> 
> Unfortunately, it doesn't guarantee allocating all slots in the array,
> but it's easy to call it in a loop and return an error if no progress
> occurs. Similar code can be found in xfs/xfs_buf.c:xfs_buf_alloc_pages().
> 
> Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Reviewed-by: Nikolay Borisov <nborisov@suse.com>