On Mon, Nov 07, 2016 at 10:50:38AM +0800, kernel test robot wrote:
>
> Greeting,
>
> FYI, we noticed a -12.7% regression of will-it-scale.per_process_ops due to
> commit:
>
>
> commit adb402cd1461eef6e1a21db4532a3b9e6a6be853 ("x86/copy_user: Unify the
> code by removing the 64-bit asm _copy_*_user() variants")
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/asm
>
> in testcase: will-it-scale
> on test machine: 8 threads Intel(R) Core(TM) i7 CPU 870 @ 2.93GHz with 4G
> memory
> with following parameters:
>
> test: poll1
> cpufreq_governor: performance
...
> # Lock Debugging (spinlocks, mutexes, etc...)
> #
> # CONFIG_DEBUG_RT_MUTEXES is not set
> # CONFIG_DEBUG_SPINLOCK is not set
> # CONFIG_DEBUG_MUTEXES is not set
> # CONFIG_DEBUG_WW_MUTEX_SLOWPATH is not set
> # CONFIG_DEBUG_LOCK_ALLOC is not set
> # CONFIG_PROVE_LOCKING is not set
> # CONFIG_LOCK_STAT is not set
> CONFIG_DEBUG_ATOMIC_SLEEP=y
^^^^^^^^^^^^^^^^^^^^^^^^^
So Mel says that this might be the culprit for the observed
change in perf. Can you please rerun your test without that
CONFIG_DEBUG_ATOMIC_SLEEP thing?
Thanks.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
