On Tue, Jan 13, 2026 at 04:01:51PM -0800, Eric Biggers wrote: > On Tue, Jan 13, 2026 at 04:27:35PM +0800, Feng Jiang wrote: > > To support performance benchmarking in KUnit tests, extract the > > generic C implementation of strlen() into a standalone function > > __generic_strlen(). This allows tests to compare architecture-optimized > > versions against the generic baseline without duplicating code.
... > A similar problem exists with the architecture-optimized CRC and crypto > functions. Historically, these subsystems exported both generic and > architecture-optimized functions. > > We've actually been moving away from that design to simplify things. > For example, for CRC-32C there's now just the crc32c() function which > delegates to the "best" CRC-32C implementation, with no direct access to > the generic implementation of CRC-32C. > > crc_kunit then just tests and benchmarks crc32c(). To check how the > performance of crc32c() changes when its implementation changes (whether > the change is the addition of an arch-optimized implementation or a > change in an existing arch-optimized implementation), the developer just > needs to run crc_kunit with two kernels, before and after. > > I suggest just doing that. In that case there would be no need to > export the generic implementations of these functions. This also would work for me! Whatever, folks, you find the best from the readability and maintenance point of view. > (Also note that *if* the generic functions are exported, they probably > should be exported only when the KUnit test is enabled. There's no need > to include them in the kernel image when the test isn't enabled.) True. -- With Best Regards, Andy Shevchenko
