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f65e908606
Remove the VAES+AVX10/256 optimized implementation of AES-GCM.
It's no longer expected to be useful for future CPUs, since Intel
changed the AVX10 specification to require 512-bit vectors.
In addition, it's no longer very useful to serve as the 256-bit fallback
for older Intel CPUs (Ice Lake and Tiger Lake) that downclock too
eagerly when 512-bit vectors are used. This is because I ended up
writing another 256-bit implementation anyway, using VAES+AVX2. The
VAES+AVX2 implementation is almost as fast as the VAES+AVX10/256 one, as
shown by the following tables. So, let's just use it instead.
Table 1: AES-256-GCM encryption throughput change,
CPU vs. message length in bytes:
| 16384 | 4096 | 4095 | 1420 | 512 | 500 |
----------------------+-------+-------+-------+-------+-------+-------+
Intel Ice Lake Server | -2% | -1% | 0% | -2% | -2% | 3% |
| 300 | 200 | 64 | 63 | 16 |
----------------------+-------+-------+-------+-------+-------+
Intel Ice Lake Server | 1% | 0% | 4% | 2% | -6% |
Table 2: AES-256-GCM decryption throughput change,
CPU vs. message length in bytes:
| 16384 | 4096 | 4095 | 1420 | 512 | 500 |
----------------------+-------+-------+-------+-------+-------+-------+
Intel Ice Lake Server | -1% | -1% | 1% | -2% | 0% | 2% |
| 300 | 200 | 64 | 63 | 16 |
----------------------+-------+-------+-------+-------+-------+
Intel Ice Lake Server | -1% | 4% | 1% | 0% | -5% |
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20251002023117.37504-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
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.