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ecb8bd70d5
Without -O2, the generated code for testing chacha function is awful. GCC even implements rol32() as a function of 20 instructions instead of just using the rotlwi instruction. ~# time ./vdso_test_chacha TAP version 13 1..1 ok 1 chacha: PASS real 0m 37.16s user 0m 36.89s sys 0m 0.26s Several other selftests directory add -O2, and the kernel is also always built with optimisation active. Do the same for vDSO selftests. With this patch the time is reduced by approximately 15%. ~# time ./vdso_test_chacha TAP version 13 1..1 ok 1 chacha: PASS real 0m 32.09s user 0m 31.86s sys 0m 0.22s Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.