[0/2] crypto: arm64/ghash-ce - performance improvements

Message

Ard Biesheuvel Aug. 4, 2018, 6:46 p.m. UTC

Another bit of performance work on the GHASH driver: this time it is not
the combined AES/GCM algorithm but the bare GHASH driver that gets updated.

Even though ARM cores that implement the polynomical multiplication
instructions that these routines depend on are guaranteed to also support
the AES instructions, and can thus use the AES/GCM driver, there could
be reasons to use the accelerated GHASH in isolation, e.g., with another
symmetric blockcipher, with a faster h/w accelerator, or potentially with
an accelerator that does not expose the AES key to the OS.

The resulting code runs at 1.1 cycles per byte on Cortex-A53 (down from
2.4 cycles per byte)

Ard Biesheuvel (2):
  crypto: arm64/ghash-ce - replace NEON yield check with block limit
  crypto: arm64/ghash-ce - implement 4-way aggregation

 arch/arm64/crypto/ghash-ce-core.S | 153 ++++++++++++++------
 arch/arm64/crypto/ghash-ce-glue.c |  87 ++++++-----
 2 files changed, 161 insertions(+), 79 deletions(-)

Comments

Herbert Xu Aug. 7, 2018, 9:53 a.m. UTC | #1

On Sat, Aug 04, 2018 at 08:46:23PM +0200, Ard Biesheuvel wrote:
> Another bit of performance work on the GHASH driver: this time it is not
> the combined AES/GCM algorithm but the bare GHASH driver that gets updated.
> 
> Even though ARM cores that implement the polynomical multiplication
> instructions that these routines depend on are guaranteed to also support
> the AES instructions, and can thus use the AES/GCM driver, there could
> be reasons to use the accelerated GHASH in isolation, e.g., with another
> symmetric blockcipher, with a faster h/w accelerator, or potentially with
> an accelerator that does not expose the AES key to the OS.
> 
> The resulting code runs at 1.1 cycles per byte on Cortex-A53 (down from
> 2.4 cycles per byte)
> 
> Ard Biesheuvel (2):
>   crypto: arm64/ghash-ce - replace NEON yield check with block limit
>   crypto: arm64/ghash-ce - implement 4-way aggregation
> 
>  arch/arm64/crypto/ghash-ce-core.S | 153 ++++++++++++++------
>  arch/arm64/crypto/ghash-ce-glue.c |  87 ++++++-----
>  2 files changed, 161 insertions(+), 79 deletions(-)

All applied.  Thanks.