[x86, vdso] cfda7bb9ecb: +14.7% will-it-scale.per_thread_ops

[Jet Chen <jet.chen@intel.com>]

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Hi Andy,

FYI, we noticed the below changes on

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/vdso
commit cfda7bb9ecbf9d96264bb5bade33a842966d1062 ("x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.c")

test case: nhm4/will-it-scale/sched_yield

3d7ee969bffcc98  cfda7bb9ecbf9d96264bb5bad
---------------  -------------------------
     5497021 ~ 0%     +14.7%    6303424 ~ 0%  TOTAL will-it-scale.per_thread_ops
        0.54 ~ 0%      +5.6%       0.57 ~ 0%  TOTAL will-it-scale.scalability
     6209483 ~ 0%      +1.6%    6305917 ~ 0%  TOTAL will-it-scale.per_process_ops
        2455 ~ 5%     +16.9%       2870 ~ 5%  TOTAL cpuidle.C1-NHM.usage
        8829 ~ 7%     +15.2%      10169 ~10%  TOTAL slabinfo.kmalloc-64.active_objs
       24.13 ~12%     +48.9%      35.93 ~14%  TOTAL time.user_time
         393 ~ 0%      -3.0%        382 ~ 1%  TOTAL time.system_time


Legend:
	~XX%    - stddev percent
	[+-]XX% - change percent


Thanks,
Jet



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echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu2/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu3/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu4/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu5/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu6/cpufreq/scaling_governor
echo performance > /sys/devices/system/cpu/cpu7/cpufreq/scaling_governor
./runtest.py sched_yield 32 1 4 6 8