On Wed, Aug 19, 2020 at 12:06 AM kernel test robot
<rong.a.c...@intel.com> wrote:
>
> Greeting,
>
> FYI, we noticed a -2.2% regression of unixbench.score due to commit:
>
>
> commit: e2ae9bcc4aaacda04edb75c4eea93384719efaa5 ("driver core: Add support
> for linking devices during device addition")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
>
>
> in testcase: unixbench
> on test machine: 96 threads Intel(R) Xeon(R) Gold 6252 CPU @ 2.10GHz with
> 192G memory
> with following parameters:
>
> runtime: 300s
> nr_task: 1
> test: syscall
> cpufreq_governor: performance
> ucode: 0x5002f01
>
> test-description: UnixBench is the original BYTE UNIX benchmark suite aims to
> test performance of Unix-like system.
> test-url: https://github.com/kdlucas/byte-unixbench
>
> In addition to that, the commit also has significant impact on the following
> tests:
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <rong.a.c...@intel.com>
>
>
> Details are as below:
> -------------------------------------------------------------------------------------------------->
>
>
> To reproduce:
>
> git clone https://github.com/intel/lkp-tests.git
> cd lkp-tests
> bin/lkp install job.yaml # job file is attached in this email
> bin/lkp run job.yaml
>
> =========================================================================================
> compiler/cpufreq_governor/kconfig/nr_task/rootfs/runtime/tbox_group/test/testcase/ucode:
>
> gcc-9/performance/x86_64-rhel-8.3/1/debian-10.4-x86_64-20200603.cgz/300s/lkp-csl-2sp8/syscall/unixbench/0x5002f01
>
> commit:
> 372a67c0c5 ("driver core: Add fwnode_to_dev() to look up device from
> fwnode")
> e2ae9bcc4a ("driver core: Add support for linking devices during device
> addition")
I'm ignoring this report for the following reasons:
1. These commits are almost a year old.
2. Code added by these commits have been changed quite a bit since
them to make them faster.
3. And most importantly, this code is effectively a NOP in a system
without devicetree firmware. I'm fairly certain this x86 Xeon system
isn't running off a DT firmware :)
-Saravana
