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X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org Hi David, David Laight writes: > How must does this conditional cost for the normal case > when it is true? > I suspect it is mispredicted 50% of the time. > So, while it may speed up your test, the overall system > impact will be negative. We have done some measures to evaluate the cost of the additional test and we don't see any noticeable impact on performances. If this is still a concern, we can add compilation-time check on CONFIG_ULP_DDP i.e. ifdef or IS_ENABLED() (which gets optimized out). Thanks