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[34.86.5.128]) by smtp.gmail.com with UTF8SMTPSA id 71dfb90a1353d-53b2bd5514csm2570233e0c.6.2025.08.19.06.55.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Aug 2025 06:55:16 -0700 (PDT) Date: Tue, 19 Aug 2025 09:55:16 -0400 From: Willem de Bruijn To: Pengtao He , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Willem de Bruijn , Mina Almasry , Jason Xing , Michal Luczaj , Eric Biggers , Alexander Lobakin Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pengtao He Message-ID: In-Reply-To: <20250819021551.8361-1-hept.hept.hept@gmail.com> References: <20250819021551.8361-1-hept.hept.hept@gmail.com> Subject: Re: [PATCH net-next v5] net: avoid one loop iteration in __skb_splice_bits Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Pengtao He wrote: > If *len is equal to 0 at the beginning of __splice_segment > it returns true directly. But when decreasing *len from > a positive number to 0 in __splice_segment, it returns false. > The __skb_splice_bits needs to call __splice_segment again. > > Recheck *len if it changes, return true in time. > Reduce unnecessary calls to __splice_segment. > > Signed-off-by: Pengtao He Reviewed-by: Willem de Bruijn