[v4,0/2] x86_64 AES-GCM improvements

Message

Eric Biggers May 27, 2024, 7:56 a.m. UTC

This patchset adds a VAES and AVX512 / AVX10 implementation of AES-GCM
(Galois/Counter Mode), which improves AES-GCM performance by up to 162%.
In addition, it replaces the old AES-NI GCM code from Intel with new
code that is slightly faster and fixes a number of issues including the
massive binary size of over 250 KB.  See the patches for details.

The end state of the x86_64 AES-GCM assembly code is that we end up with
two assembly files, one that generates AES-NI code with or without AVX,
and one that generates VAES code with AVX512 / AVX10 with 256-bit or
512-bit vectors.  There's no support for VAES alone (without AVX512 /
AVX10).  This differs slightly from what I did with AES-XTS where one
file generates both AVX and AVX512 / AVX10 code including code using
VAES alone (without AVX512 / AVX10), and another file generates non-AVX
code only.  For now this seems like the right choice for each particular
algorithm, though, based on how much being limited to 16 SIMD registers
and 128-bit vectors resulted in some significantly different design
choices for AES-GCM, but not quite as much for AES-XTS.  CPUs shipping
with VAES alone also seems to be a temporary thing, so we perhaps
shouldn't go too much out of our way to support that combination.

Changed in v4:
- Added AES-NI rewrite patch.
- Adjusted the VAES-AVX10 patch slightly to make it possible to cleanly
  add the AES-NI support on top of it.

Changed in v3:
- Optimized the finalization code slightly.
- Fixed a minor issue in my userspace benchmark program (guard page
  after key struct made "AVX512_Cloudflare" extra slow on some input
  lengths) and regenerated tables 3-4.  Also upgraded to Emerald Rapids.
- Eliminated an instruction from _aes_gcm_precompute.

Changed in v2:
- Additional assembly optimizations
- Improved some comments
- Aligned key struct to 64 bytes
- Added comparison with Cloudflare's implementation of AES-GCM
- Other cleanups

Eric Biggers (2):
  crypto: x86/aes-gcm - add VAES and AVX512 / AVX10 optimized AES-GCM
  crypto: x86/aes-gcm - rewrite the AES-NI optimized AES-GCM

 arch/x86/crypto/Kconfig                  |    1 +
 arch/x86/crypto/Makefile                 |    8 +-
 arch/x86/crypto/aes-gcm-aesni-x86_64.S   | 1131 +++++++++
 arch/x86/crypto/aes-gcm-avx10-x86_64.S   | 1222 ++++++++++
 arch/x86/crypto/aesni-intel_asm.S        | 1503 +-----------
 arch/x86/crypto/aesni-intel_avx-x86_64.S | 2804 ----------------------
 arch/x86/crypto/aesni-intel_glue.c       | 1269 ++++++----
 7 files changed, 3128 insertions(+), 4810 deletions(-)
 create mode 100644 arch/x86/crypto/aes-gcm-aesni-x86_64.S
 create mode 100644 arch/x86/crypto/aes-gcm-avx10-x86_64.S
 delete mode 100644 arch/x86/crypto/aesni-intel_avx-x86_64.S


base-commit: 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0