Description of problem:

When I log into Gnome/Gnome Classic and run powertop I notice that the amount of WAKEUPS is in the range of 100-300. In contrast, when I log into Gnome on Wayland the amount of wakeups are typically ~50. The top two sources of the high amount of wakups are reported as "[rcu_shed]" and "/usr/bin/gnome-shell". Next I run lscpu to get the current speed, and I notice that on Gnome/Gnome Classic the processor speed is always maxed out and never idling. Gnome on Wayland works as expected and actually idles to the minimum frequency. 


Version-Release number of selected component (if applicable): Gnome 3.18


Steps to Reproduce:
1. Run powertop on Gnome/Gnome Classic vs Gnome on Wayland. "[rcu_shed]" and "/usr/bin/gnome-shell" producing the main source of the wakeups on Gnome/Gnome Classic

2. Run lscpu to show that clock speed is always at max on Gnome/Gnome Classic, but idles to minimum on Gnome on Wayland


Additional info:

H/W path           Device  Class          Description
=====================================================
                           system         Computer
/0                         bus            Motherboard
/0/0                       memory         7892MiB System memory
/0/1                       processor      Intel(R) Core(TM) i5-4288U CPU
/0/100                     bridge         Haswell-ULT DRAM Controller
/0/100/2                   display        Haswell-ULT Integrated Graphics 
/0/100/3                   multimedia     Haswell-ULT HD Audio Controller
/0/100/14                  bus            8 Series USB xHCI HC
/0/100/16                  communication  8 Series HECI #0
/0/100/1b                  multimedia     8 Series HD Audio Controller
/0/100/1c                  bridge         8 Series PCI Express Root Port 1
/0/100/1c.1                bridge         8 Series PCI Express Root Port 2
/0/100/1c.1/0              multimedia     720p FaceTime HD Camera
/0/100/1c.2                bridge         8 Series PCI Express Root Port 3
/0/100/1c.2/0              network        BCM4360 802.11ac Wireless
/0/100/1c.4                bridge         8 Series PCI Express Root Port 5
/0/100/1c.4/0              bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/0            bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/0/0          generic        DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/3            bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/4            bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/5            bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.4/0/6            bridge         DSL5520 Thunderbolt [Falcon Ridge]
/0/100/1c.5                bridge         8 Series PCI Express Root Port 6
/0/100/1c.5/0              storage        Apple PCIe SSD
/0/100/1f                  bridge         8 Series LPC Controller
/0/100/1f.3                bus            8 Series SMBus Controller
/1                 scsi1   storage