X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=kernel%2Fcontext_tracking.c;h=d8560ee3bab788c15be6d1be8eb610473fc5c4b5;hb=a3b11c79addf5613c4a10b27349f862e1e0f5bfe;hp=6d4c6ce212753025c6b1000277e282979bf57720;hpb=f70cd6b07e629f367bb9b1ac9d0e3e669eb325c0;p=deliverable%2Flinux.git diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index 6d4c6ce21275..d8560ee3bab7 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -58,27 +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; - - /* - * 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)) { @@ -111,7 +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); @@ -135,16 +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 (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)) { @@ -161,7 +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);