Pull scheduler updates from Ingo Molnar:
- membarrier updates (Mathieu Desnoyers)
- SMP balancing optimizations (Mel Gorman)
- stats update optimizations (Peter Zijlstra)
- RT scheduler race fixes (Steven Rostedt)
- misc fixes and updates
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Use a recently used CPU as an idle candidate and the basis for SIS
sched/fair: Do not migrate if the prev_cpu is idle
sched/fair: Restructure wake_affine*() to return a CPU id
sched/fair: Remove unnecessary parameters from wake_affine_idle()
sched/rt: Make update_curr_rt() more accurate
sched/rt: Up the root domain ref count when passing it around via IPIs
sched/rt: Use container_of() to get root domain in rto_push_irq_work_func()
sched/core: Optimize update_stats_*()
sched/core: Optimize ttwu_stat()
membarrier/selftest: Test private expedited sync core command
membarrier/arm64: Provide core serializing command
membarrier/x86: Provide core serializing command
membarrier: Provide core serializing command, *_SYNC_CORE
lockin/x86: Implement sync_core_before_usermode()
locking: Introduce sync_core_before_usermode()
membarrier/selftest: Test global expedited command
membarrier: Provide GLOBAL_EXPEDITED command
membarrier: Document scheduler barrier requirements
powerpc, membarrier: Skip memory barrier in switch_mm()
membarrier/selftest: Test private expedited command