Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "The main scheduler changes in this cycle were:

   - support Intel Turbo Boost Max Technology 3.0 (TBM3) by introducig a
     notion of 'better cores', which the scheduler will prefer to
     schedule single threaded workloads on. (Tim Chen, Srinivas
     Pandruvada)

   - enhance the handling of asymmetric capacity CPUs further (Morten
     Rasmussen)

   - improve/fix load handling when moving tasks between task groups
     (Vincent Guittot)

   - simplify and clean up the cputime code (Stanislaw Gruszka)

   - improve mass fork()ed task spread a.k.a. hackbench speedup (Vincent
     Guittot)

   - make struct kthread kmalloc()ed and related fixes (Oleg Nesterov)

   - add uaccess atomicity debugging (when using access_ok() in the
     wrong context), under CONFIG_DEBUG_ATOMIC_SLEEP=y (Peter Zijlstra)

   - implement various fixes, cleanups and other enhancements (Daniel
     Bristot de Oliveira, Martin Schwidefsky, Rafael J. Wysocki)"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  sched/core: Use load_avg for selecting idlest group
  sched/core: Fix find_idlest_group() for fork
  kthread: Don't abuse kthread_create_on_cpu() in __kthread_create_worker()
  kthread: Don't use to_live_kthread() in kthread_[un]park()
  kthread: Don't use to_live_kthread() in kthread_stop()
  Revert "kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function"
  kthread: Make struct kthread kmalloc'ed
  x86/uaccess, sched/preempt: Verify access_ok() context
  sched/x86: Make CONFIG_SCHED_MC_PRIO=y easier to enable
  sched/x86: Change CONFIG_SCHED_ITMT to CONFIG_SCHED_MC_PRIO
  x86/sched: Use #include <linux/mutex.h> instead of #include <asm/mutex.h>
  cpufreq/intel_pstate: Use CPPC to get max performance
  acpi/bus: Set _OSC for diverse core support
  acpi/bus: Enable HWP CPPC objects
  x86/sched: Add SD_ASYM_PACKING flags to x86 ITMT CPU
  x86/sysctl: Add sysctl for ITMT scheduling feature
  x86: Enable Intel Turbo Boost Max Technology 3.0
  x86/topology: Define x86's arch_update_cpu_topology
  sched: Extend scheduler's asym packing
  sched/fair: Clean up the tunable parameter definitions
  ...

arch/x86/include/asm/preempt.h

@@ -24,7 +24,13 @@ static __always_inline int preempt_count(void)
 
 static __always_inline void preempt_count_set(int pc)
 {
-	raw_cpu_write_4(__preempt_count, pc);
+	int old, new;
+
+	do {
+		old = raw_cpu_read_4(__preempt_count);
+		new = (old & PREEMPT_NEED_RESCHED) |
+			(pc & ~PREEMPT_NEED_RESCHED);
+	} while (raw_cpu_cmpxchg_4(__preempt_count, old, new) != old);
 }
 
 /*

arch/x86/include/asm/topology.h

@@ -146,4 +146,36 @@ struct pci_bus;
 int x86_pci_root_bus_node(int bus);
 void x86_pci_root_bus_resources(int bus, struct list_head *resources);
 
+extern bool x86_topology_update;
+
+#ifdef CONFIG_SCHED_MC_PRIO
+#include <asm/percpu.h>
+
+DECLARE_PER_CPU_READ_MOSTLY(int, sched_core_priority);
+extern unsigned int __read_mostly sysctl_sched_itmt_enabled;
+
+/* Interface to set priority of a cpu */
+void sched_set_itmt_core_prio(int prio, int core_cpu);
+
+/* Interface to notify scheduler that system supports ITMT */
+int sched_set_itmt_support(void);
+
+/* Interface to notify scheduler that system revokes ITMT support */
+void sched_clear_itmt_support(void);
+
+#else /* CONFIG_SCHED_MC_PRIO */
+
+#define sysctl_sched_itmt_enabled	0
+static inline void sched_set_itmt_core_prio(int prio, int core_cpu)
+{
+}
+static inline int sched_set_itmt_support(void)
+{
+	return 0;
+}
+static inline void sched_clear_itmt_support(void)
+{
+}
+#endif /* CONFIG_SCHED_MC_PRIO */
+
 #endif /* _ASM_X86_TOPOLOGY_H */

arch/x86/include/asm/uaccess.h

@@ -68,6 +68,12 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un
 	__chk_range_not_ok((unsigned long __force)(addr), size, limit); \
 })
 
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+# define WARN_ON_IN_IRQ()	WARN_ON_ONCE(!in_task())
+#else
+# define WARN_ON_IN_IRQ()
+#endif
+
 /**
  * access_ok: - Checks if a user space pointer is valid
  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
@@ -88,8 +94,11 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un
  * checks that the pointer is in the user space range - after calling
  * this function, memory access functions may still return -EFAULT.
  */
-#define access_ok(type, addr, size) \
-	likely(!__range_not_ok(addr, size, user_addr_max()))
+#define access_ok(type, addr, size)					\
+({									\
+	WARN_ON_IN_IRQ();						\
+	likely(!__range_not_ok(addr, size, user_addr_max()));		\
+})
 
 /*
  * These are the main single-value transfer routines.  They automatically