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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4924923c862sm262149435e9.7.2026.06.23.01.25.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jun 2026 01:25:02 -0700 (PDT) Date: Tue, 23 Jun 2026 09:25:01 +0100 From: David Laight To: David Hu Cc: Sumit Semwal , Christian =?UTF-8?B?S8O2bmln?= , Jason Gunthorpe , Nicolin Chen , Leon Romanovsky , Kevin Tian , Ankit Agrawal , Alex Williamson , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, jmoroni@google.com, praan@google.com, kpberry@google.com, sashiko-bot , stable@vger.kernel.org Subject: Re: [PATCH] dma-buf: Split sgl by largest page-aligned chunk Message-ID: <20260623092501.17bef195@pumpkin> In-Reply-To: References: <20260621222130.1667453-1-xuehaohu@google.com> <20260622091344.794e0d74@pumpkin> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 22 Jun 2026 17:26:10 -0400 David Hu wrote: > On Mon, Jun 22, 2026 at 4:13=E2=80=AFAM David Laight > wrote: > > =20 >=20 > Hi David, >=20 > Thank you for your review. You raised many good points regarding > optimizations here. I'll switch to using 2G as the max entry size > (`SZ_2G` from `linux/sizes.h`), and remove divisions and > multiplications. I'll also replace the `for()` loop with `while > (length)`, and drop `min_t()` in favor of `min()` by casting `SZ_2G` > to `size_t`. You shouldn't need a cast at all. David L. > I'll send out a v2 with these changes shortly. >=20 > Thanks, > David