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Miller" , Jakub Kicinski , "netdev@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] net: Remove branch in csum_shift() Message-ID: References: <7f16910a8f63475dae012ef5135f41d1@AcuMS.aculab.com> <20220213091619.GY614@gate.crashing.org> <476aa649389345db92f86e9103a848be@AcuMS.aculab.com> <9cdb4a5243d342efb562bc61d0c1bfcb@AcuMS.aculab.com> <10309fa64833418a980a8d950d037357@AcuMS.aculab.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <10309fa64833418a980a8d950d037357@AcuMS.aculab.com> Sender: Russell King (Oracle) X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 01, 2022 at 11:41:06AM +0000, David Laight wrote: > From: Christophe Leroy > > Sent: 01 March 2022 11:15 > ... > > Looks like ARM also does better code with the generic implementation as > > it seems to have some looking like conditional instructions 'rorne' and > > 'strne'. > > In arm32 (and I think arm64) every instruction is conditional. Almost every instruction in arm32. There are a number of unconditional instructions that were introduced. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!