[linux-next:master] [crypto] bb897c5504: stress-ng.af-alg.ops_per_sec -8.0% regression

Hello,

kernel test robot noticed a -8.0% regression of stress-ng.af-alg.ops_per_sec on:


commit: bb897c55042e9330bcf88b4b13cbdd6f9fabdd5e ("crypto: jitter - replace LFSR with SHA3-256")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

testcase: stress-ng
test machine: 36 threads 1 sockets Intel(R) Core(TM) i9-10980XE CPU @ 3.00GHz (Cascade Lake) with 128G memory
parameters:

	nr_threads: 1
	disk: 1HDD
	testtime: 60s
	fs: ext4
	class: os
	test: af-alg
	cpufreq_governor: performance




If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot [off-list ref]
| Closes: https://lore.kernel.org/oe-lkp/202306081658.d5c86ae9-oliver.sang@intel.com


Details are as below:
-------------------------------------------------------------------------------------------------->


To reproduce:

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        sudo bin/lkp install job.yaml           # job file is attached in this email

232 more lines

Am Freitag, 9. Juni 2023, 10:02:32 CEST schrieb kernel test robot:

Hi,

Hello,

kernel test robot noticed a -8.0% regression of stress-ng.af-alg.ops_per_sec
on:


commit: bb897c55042e9330bcf88b4b13cbdd6f9fabdd5e ("crypto: jitter - replace
LFSR with SHA3-256")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

testcase: stress-ng
test machine: 36 threads 1 sockets Intel(R) Core(TM) i9-10980XE CPU @
3.00GHz (Cascade Lake) with 128G memory parameters:

Thank you for the report, but this change in performance is expected to ensure 
proper entropy collection. I assume that the jitterentropy_rng is queried via 
AF_ALG. Considering that the amount of data to be generated (and thus the 
effect of the performance degradation) is small, there should be no noticeable 
impact on users.

Ciao
Stephan

hi, Stephan,

On Fri, Jun 09, 2023 at 01:57:27PM +0200, Stephan Mueller wrote:

Am Freitag, 9. Juni 2023, 10:02:32 CEST schrieb kernel test robot:

Hi,

quoted

Hello,

kernel test robot noticed a -8.0% regression of stress-ng.af-alg.ops_per_sec
on:


commit: bb897c55042e9330bcf88b4b13cbdd6f9fabdd5e ("crypto: jitter - replace
LFSR with SHA3-256")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

testcase: stress-ng
test machine: 36 threads 1 sockets Intel(R) Core(TM) i9-10980XE CPU @
3.00GHz (Cascade Lake) with 128G memory parameters:

Thank you for the report, but this change in performance is expected to ensure 
proper entropy collection. I assume that the jitterentropy_rng is queried via 
AF_ALG. Considering that the amount of data to be generated (and thus the 
effect of the performance degradation) is small, there should be no noticeable 
impact on users.

got it. Thanks a lot for information!

Ciao
Stephan