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Date: Thu, 31 Jul 2025 08:29:42 -0700
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Subject: Re: [PATCH v2 3/3] zram: enable asynchronous writeback
To: Richard Chang <richardycc@google.com>, Minchan Kim <minchan@kernel.org>,
 Sergey Senozhatsky <senozhatsky@chromium.org>, Jens Axboe <axboe@kernel.dk>,
 Andrew Morton <akpm@linux-foundation.org>
Cc: bgeffon@google.com, liumartin@google.com, linux-kernel@vger.kernel.org,
 linux-block@vger.kernel.org, linux-mm@kvack.org
References: <20250731064949.1690732-1-richardycc@google.com>
 <20250731064949.1690732-4-richardycc@google.com>
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From: Bart Van Assche <bvanassche@acm.org>
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On 7/30/25 11:49 PM, Richard Chang wrote:
> +	bio = bio_alloc(zram->bdev, 1, REQ_OP_WRITE, GFP_NOIO | __GFP_NOWARN);
> +	if (!bio) {
> +		err = -ENOMEM;
> +		goto out_free_page;
> +	}
> +
> +	req = kmalloc(sizeof(struct zram_wb_request), GFP_NOIO | __GFP_NOWARN);
> +	if (!req) {
> +		err = -ENOMEM;
> +		goto out_free_bio;
> +	}

Why are 'req' and 'bio' allocated separately instead of creating a
bio_set with front padding? See also bioset_init().

Thanks,

Bart.