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

Pull scheduler changes from Ingo Molnar:
 "Main changes:

   - scheduler side full-dynticks (user-space execution is undisturbed
     and receives no timer IRQs) preparation changes that convert the
     cputime accounting code to be full-dynticks ready, from Frederic
     Weisbecker.

   - Initial sched.h split-up changes, by Clark Williams

   - select_idle_sibling() performance improvement by Mike Galbraith:

        " 1 tbench pair (worst case) in a 10 core + SMT package:

          pre   15.22 MB/sec 1 procs
          post 252.01 MB/sec 1 procs "

  - sched_rr_get_interval() ABI fix/change.  We think this detail is not
    used by apps (so it's not an ABI in practice), but lets keep it
    under observation.

  - misc RT scheduling cleanups, optimizations"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  sched/rt: Add <linux/sched/rt.h> header to <linux/init_task.h>
  cputime: Remove irqsave from seqlock readers
  sched, powerpc: Fix sched.h split-up build failure
  cputime: Restore CPU_ACCOUNTING config defaults for PPC64
  sched/rt: Move rt specific bits into new header file
  sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice
  sched: Move sched.h sysctl bits into separate header
  sched: Fix signedness bug in yield_to()
  sched: Fix select_idle_sibling() bouncing cow syndrome
  sched/rt: Further simplify pick_rt_task()
  sched/rt: Do not account zero delta_exec in update_curr_rt()
  cputime: Safely read cputime of full dynticks CPUs
  kvm: Prepare to add generic guest entry/exit callbacks
  cputime: Use accessors to read task cputime stats
  cputime: Allow dynamic switch between tick/virtual based cputime accounting
  cputime: Generic on-demand virtual cputime accounting
  cputime: Move default nsecs_to_cputime() to jiffies based cputime file
  cputime: Librarize per nsecs resolution cputime definitions
  cputime: Avoid multiplication overflow on utime scaling
  context_tracking: Export context state for generic vtime
  ...

Fix up conflict in kernel/context_tracking.c due to comment additions.

1 files changed, 25 insertions, 18 deletions

diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index d566aba7e801..65349f07b878 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -15,26 +15,13 @@
  */
 
 #include <linux/context_tracking.h>
+#include <linux/kvm_host.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
-#include <linux/percpu.h>
 #include <linux/hardirq.h>
+#include <linux/export.h>
 
-struct context_tracking {
-	/*
-	 * When active is false, probes are unset in order
-	 * to minimize overhead: TIF flags are cleared
-	 * and calls to user_enter/exit are ignored. This
-	 * may be further optimized using static keys.
-	 */
-	bool active;
-	enum {
-		IN_KERNEL = 0,
-		IN_USER,
-	} state;
-};
-
-static DEFINE_PER_CPU(struct context_tracking, context_tracking) = {
+DEFINE_PER_CPU(struct context_tracking, context_tracking) = {
 #ifdef CONFIG_CONTEXT_TRACKING_FORCE
 	.active = true,
 #endif
@@ -70,7 +57,6 @@ void user_enter(void)
 	local_irq_save(flags);
 	if (__this_cpu_read(context_tracking.active) &&
 	    __this_cpu_read(context_tracking.state) != IN_USER) {
-		__this_cpu_write(context_tracking.state, IN_USER);
 		/*
 		 * At this stage, only low level arch entry code remains and
 		 * then we'll run in userspace. We can assume there won't be
@@ -78,7 +64,9 @@ void user_enter(void)
 		 * user_exit() or rcu_irq_enter(). Let's remove RCU's dependency
 		 * on the tick.
 		 */
+		vtime_user_enter(current);
 		rcu_user_enter();
+		__this_cpu_write(context_tracking.state, IN_USER);
 	}
 	local_irq_restore(flags);
 }
@@ -104,16 +92,35 @@ void user_exit(void)
 
 	local_irq_save(flags);
 	if (__this_cpu_read(context_tracking.state) == IN_USER) {
-		__this_cpu_write(context_tracking.state, IN_KERNEL);
 		/*
 		 * We are going to run code that may use RCU. Inform
 		 * RCU core about that (ie: we may need the tick again).
 		 */
 		rcu_user_exit();
+		vtime_user_exit(current);
+		__this_cpu_write(context_tracking.state, IN_KERNEL);
 	}
 	local_irq_restore(flags);
 }
 
+void guest_enter(void)
+{
+	if (vtime_accounting_enabled())
+		vtime_guest_enter(current);
+	else
+		__guest_enter();
+}
+EXPORT_SYMBOL_GPL(guest_enter);
+
+void guest_exit(void)
+{
+	if (vtime_accounting_enabled())
+		vtime_guest_exit(current);
+	else
+		__guest_exit();
+}
+EXPORT_SYMBOL_GPL(guest_exit);
+
 
 /**
  * context_tracking_task_switch - context switch the syscall callbacks