Merge remote-tracking branch 'remotes/stable/linux-4.4.y' into karo-tx6-mainline

[karo-tx-linux.git] / kernel / context_tracking.c

diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 0a495ab35bc72b55d8eab13f0922e6fdb8099d9a..d8560ee3bab788c15be6d1be8eb610473fc5c4b5 100644 (file)
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -58,36 +58,13 @@ static void context_tracking_recursion_exit(void)
  * instructions to execute won't use any RCU read side critical section
  * because this function sets RCU in extended quiescent state.
  */
-void context_tracking_enter(enum ctx_state state)
+void __context_tracking_enter(enum ctx_state state)
 {
-       unsigned long flags;
-
-       /*
-        * Repeat the user_enter() check here because some archs may be calling
-        * this from asm and if no CPU needs context tracking, they shouldn't
-        * go further. Repeat the check here until they support the inline static
-        * key check.
-        */
-       if (!context_tracking_is_enabled())
-               return;
-
-       /*
-        * Some contexts may involve an exception occuring in an irq,
-        * leading to that nesting:
-        * rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
-        * This would mess up the dyntick_nesting count though. And rcu_irq_*()
-        * helpers are enough to protect RCU uses inside the exception. So
-        * just return immediately if we detect we are in an IRQ.
-        */
-       if (in_interrupt())
-               return;
-
        /* Kernel threads aren't supposed to go to userspace */
        WARN_ON_ONCE(!current->mm);
 
-       local_irq_save(flags);
        if (!context_tracking_recursion_enter())
-               goto out_irq_restore;
+               return;
 
        if ( __this_cpu_read(context_tracking.state) != state) {
                if (__this_cpu_read(context_tracking.active)) {
@@ -120,7 +97,27 @@ void context_tracking_enter(enum ctx_state state)
                __this_cpu_write(context_tracking.state, state);
        }
        context_tracking_recursion_exit();
-out_irq_restore:
+}
+NOKPROBE_SYMBOL(__context_tracking_enter);
+EXPORT_SYMBOL_GPL(__context_tracking_enter);
+
+void context_tracking_enter(enum ctx_state state)
+{
+       unsigned long flags;
+
+       /*
+        * Some contexts may involve an exception occuring in an irq,
+        * leading to that nesting:
+        * rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
+        * This would mess up the dyntick_nesting count though. And rcu_irq_*()
+        * helpers are enough to protect RCU uses inside the exception. So
+        * just return immediately if we detect we are in an IRQ.
+        */
+       if (in_interrupt())
+               return;
+
+       local_irq_save(flags);
+       __context_tracking_enter(state);
        local_irq_restore(flags);
 }
 NOKPROBE_SYMBOL(context_tracking_enter);
@@ -128,7 +125,7 @@ EXPORT_SYMBOL_GPL(context_tracking_enter);
 
 void context_tracking_user_enter(void)
 {
-       context_tracking_enter(CONTEXT_USER);
+       user_enter();
 }
 NOKPROBE_SYMBOL(context_tracking_user_enter);
 
@@ -144,19 +141,10 @@ NOKPROBE_SYMBOL(context_tracking_user_enter);
  * This call supports re-entrancy. This way it can be called from any exception
  * handler without needing to know if we came from userspace or not.
  */
-void context_tracking_exit(enum ctx_state state)
+void __context_tracking_exit(enum ctx_state state)
 {
-       unsigned long flags;
-
-       if (!context_tracking_is_enabled())
-               return;
-
-       if (in_interrupt())
-               return;
-
-       local_irq_save(flags);
        if (!context_tracking_recursion_enter())
-               goto out_irq_restore;
+               return;
 
        if (__this_cpu_read(context_tracking.state) == state) {
                if (__this_cpu_read(context_tracking.active)) {
@@ -173,7 +161,19 @@ void context_tracking_exit(enum ctx_state state)
                __this_cpu_write(context_tracking.state, CONTEXT_KERNEL);
        }
        context_tracking_recursion_exit();
-out_irq_restore:
+}
+NOKPROBE_SYMBOL(__context_tracking_exit);
+EXPORT_SYMBOL_GPL(__context_tracking_exit);
+
+void context_tracking_exit(enum ctx_state state)
+{
+       unsigned long flags;
+
+       if (in_interrupt())
+               return;
+
+       local_irq_save(flags);
+       __context_tracking_exit(state);
        local_irq_restore(flags);
 }
 NOKPROBE_SYMBOL(context_tracking_exit);
@@ -181,7 +181,7 @@ EXPORT_SYMBOL_GPL(context_tracking_exit);
 
 void context_tracking_user_exit(void)
 {
-       context_tracking_exit(CONTEXT_USER);
+       user_exit();
 }
 NOKPROBE_SYMBOL(context_tracking_user_exit);