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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20200113215811.GA18216@bombadil.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000106, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 1/13/20 2:58 PM, Matthew Wilcox wrote: > On Mon, Jan 13, 2020 at 06:00:52PM +0000, Chris Mason wrote: >> This is true, I didn't explain that part well ;) Depending on >> compression etc we might end up poking the xarray inside the actual IO >> functions, but the main difference is that btrfs is building a single >> bio. You're moving the plug so you'll merge into single bio, but I'd >> rather build 2MB bios than merge them. > > Why don't we store a bio pointer inside the plug? You're opencoding that, > iomap is opencoding that, and I bet there's a dozen other places where > we pass a bio around. Then blk_finish_plug can submit the bio. Plugs aren't necessarily a bio, they can be callbacks too. -- Jens Axboe