cgroup: Add generic cgroup subsystem permission checks.

    Rather than using explicit euid == 0 checks when trying to move
tasks into a cgroup via CFS, move permission checks into each
specific cgroup subsystem. If a subsystem does not specify a
'can_attach' handler, then we fall back to doing our checks the old way.

    This way non-root processes can add arbitrary processes to
a cgroup if all the registered subsystems on that cgroup agree.

    Also change explicit euid == 0 check to CAP_SYS_ADMIN

Signed-off-by: San Mehat <san@google.com>
Revert "cgroup: Add generic cgroup subsystem permission checks."

This reverts commit 1d38bc7d0523af2233b4280e2aeab34c6a076665.

Change-Id: I2c5066b696cbdd5ca117ed74718bcb7e70e878e7
Signed-off-by: Colin Cross <ccross@android.com>
scheduler: domain: init next_balance in nohz_idle_balancer with jiffies

Bug 878165

The next_balance parameter of nohz_idle_balancer should be initialized
to jiffies since jiffies itself is initialized to 300 seconds shy of
overflow. Otherwise, nohz_idle_balancer does not run for the first 5
mins after bootup.

Change-Id: I18334451f394ead8ddad3b94d725635a31e0173b
Signed-off-by: Diwakar Tundlam <dtundlam@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-on: http://git-master/r/77300
Reviewed-by: Automatic_Commit_Validation_User