Re: [RFC V1 0/7] Introduce AVX512 optimized crypto algorithms

[Eric Biggers]

On Fri, Dec 18, 2020 at 01:10:57PM -0800, Megha Dey wrote:
> Optimize crypto algorithms using VPCLMULQDQ and VAES AVX512 instructions
> (first implemented on Intel's Icelake client and Xeon CPUs).
> 
> These algorithms take advantage of the AVX512 registers to keep the CPU
> busy and increase memory bandwidth utilization. They provide substantial
> (2-10x) improvements over existing crypto algorithms when update data size
> is greater than 128 bytes and do not have any significant impact when used
> on small amounts of data.
> 
> However, these algorithms may also incur a frequency penalty and cause
> collateral damage to other workloads running on the same core(co-scheduled
> threads). These frequency drops are also known as bin drops where 1 bin
> drop is around 100MHz. With the SpecCPU and ffmpeg benchmark, a 0-1 bin
> drop(0-100MHz) is observed on Icelake desktop and 0-2 bin drops (0-200Mhz)
> are observed on the Icelake server.
> 

Do these new algorithms all pass the self-tests, including the fuzz tests that
are enabled when CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y?

- Eric