sched/cputime: Clean up the old vtime gen irqtime accounting completely

Vtime generic irqtime accounting has been removed but there are a few
remnants to clean up:

* The vtime_accounting_cpu_enabled() check in irq entry was only used
  by CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can safely remove it.

* Without the vtime_accounting_cpu_enabled(), we no longer need to
  have a vtime_common_account_irq_enter() indirect function.

* Move vtime_account_irq_enter() implementation under
  CONFIG_VIRT_CPU_ACCOUNTING_NATIVE which is the last user.

* The vtime_account_user() call was only used on irq entry for
  CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can remove that too.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 10 insertions, 34 deletions

diff --git a/include/linux/vtime.h b/include/linux/vtime.h
index d1977d84ebdf..65aef5e9d04e 100644
--- a/include/linux/vtime.h
+++ b/include/linux/vtime.h
@@ -14,18 +14,7 @@ struct task_struct;
  */
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 static inline bool vtime_accounting_cpu_enabled(void) { return true; }
-
-#ifdef __ARCH_HAS_VTIME_ACCOUNT
 extern void vtime_account_irq_enter(struct task_struct *tsk);
-#else
-extern void vtime_common_account_irq_enter(struct task_struct *tsk);
-static inline void vtime_account_irq_enter(struct task_struct *tsk)
-{
-        if (vtime_accounting_cpu_enabled())
-                vtime_common_account_irq_enter(tsk);
-}
-#endif /* __ARCH_HAS_VTIME_ACCOUNT */
-
 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index ca7e33cb0967..16a873c203b1 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -431,6 +431,10 @@ void vtime_common_task_switch(struct task_struct *prev)
 }
 #endif
 
+#endif /* CONFIG_VIRT_CPU_ACCOUNTING */
+
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 /*
  * Archs that account the whole time spent in the idle task
  * (outside irq) as idle time can rely on this and just implement
@@ -440,33 +444,16 @@ void vtime_common_task_switch(struct task_struct *prev)
  * vtime_account().
  */
 #ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_common_account_irq_enter(struct task_struct *tsk)
+void vtime_account_irq_enter(struct task_struct *tsk)
 {
-        if (!in_interrupt()) {
-                /*
-                 * If we interrupted user, context_tracking_in_user()
-                 * is 1 because the context tracking don't hook
-                 * on irq entry/exit. This way we know if
-                 * we need to flush user time on kernel entry.
-                 */
-                if (context_tracking_in_user()) {
-                        vtime_account_user(tsk);
-                        return;
-                }
-
-                if (is_idle_task(tsk)) {
-                        vtime_account_idle(tsk);
-                        return;
-                }
-        }
-        vtime_account_system(tsk);
+        if (!in_interrupt() && is_idle_task(tsk))
+                vtime_account_idle(tsk);
+        else
+                vtime_account_system(tsk);
 }
-EXPORT_SYMBOL_GPL(vtime_common_account_irq_enter);
+EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
 #endif /* __ARCH_HAS_VTIME_ACCOUNT */
-#endif /* CONFIG_VIRT_CPU_ACCOUNTING */
-
 
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
 {
         *ut = p->utime;