2c94ebedc8
Since it's likely to be useful for performance work with SVE let's have a pidbench that gives us some numbers for consideration. In order to ensure that we test exactly the scenario we want this is written in assembly - if system libraries use SVE this would stop us exercising the case where the process has never used SVE. We exercise three cases: - Never having used SVE. - Having used SVE once. - Using SVE after each syscall. by spinning running getpid() for a fixed number of iterations with the time measured using CNTVCT_EL0 reported on the console. This is obviously a totally unrealistic benchmark which will show the extremes of any performance variation but equally given the potential gotchas with use of FP instructions by system libraries it's good to have some concrete code shared to make it easier to compare notes on results. Testing over multiple SVE vector lengths will need to be done with vlset currently, the test could be extended to iterate over all of them if desired. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20211202165107.1075259-1-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
KSelfTest ARM64
===============
- These tests are arm64 specific and so not built or run but just skipped
completely when env-variable ARCH is found to be different than 'arm64'
and `uname -m` reports other than 'aarch64'.
- Holding true the above, ARM64 KSFT tests can be run within the KSelfTest
framework using standard Linux top-level-makefile targets:
$ make TARGETS=arm64 kselftest-clean
$ make TARGETS=arm64 kselftest
or
$ make -C tools/testing/selftests TARGETS=arm64 \
INSTALL_PATH=<your-installation-path> install
or, alternatively, only specific arm64/ subtargets can be picked:
$ make -C tools/testing/selftests TARGETS=arm64 ARM64_SUBTARGETS="tags signal" \
INSTALL_PATH=<your-installation-path> install
Further details on building and running KFST can be found in:
Documentation/dev-tools/kselftest.rst