Perf: Fix hrtimer operation across hotplug

Stop hrtimer associated with CPU clock event when
core goes down. Start the timer when core comes back up.
This is needed to ensure proper software timer operation
across hotplug.

Change-Id: I027bf2718d177fa31be2a7cfe7ef98f93cb4aeda
Signed-off-by: Sheetal Sahasrabudhe <sheetals@codeaurora.org>
Perf: add perf user-mode permissions

Allow user-mode applications to use the performance
counters for debugging and performance analysis.

Change-Id: I0caed53dafb9965b8eece92762a0b67a40ff3be5
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
Perf: Add event type check in hrtimer hotplug fix

The hrtimer hotplug fix was missing event_type check due to which
the check was passing both software clock and hardware cycles.

Change-Id: I1d16d0ccc6ce27963ace9d2f3e1e1eab8f8c7d18
Signed-off-by: Sheetal Sahasrabudhe <sheetals@codeaurora.org>
Perf: Add debugfs node to clear PMU

Create debugfs node to clear PMU and some internal variables
used by Perf code. This provides a recovery path for
PMU related unexpected error scenarios.

Change-Id: I88ae9dda0888db9316ce123f6f3a58faec4d69ee
Signed-off-by: Sheetal Sahasrabudhe <sheetals@codeaurora.org>

Conflicts:
	arch/arm/Kconfig

Change-Id: Ia3160eee21b024c89b42a69b68a97e0bac131d12