summaryrefslogtreecommitdiffstats
path: root/kernel/context_tracking.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/context_tracking.c')
-rw-r--r--kernel/context_tracking.c40
1 files changed, 0 insertions, 40 deletions
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 5664985c46a0..937ecdfdf258 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -107,46 +107,6 @@ void context_tracking_user_enter(void)
}
NOKPROBE_SYMBOL(context_tracking_user_enter);
-#ifdef CONFIG_PREEMPT
-/**
- * preempt_schedule_context - preempt_schedule called by tracing
- *
- * The tracing infrastructure uses preempt_enable_notrace to prevent
- * recursion and tracing preempt enabling caused by the tracing
- * infrastructure itself. But as tracing can happen in areas coming
- * from userspace or just about to enter userspace, a preempt enable
- * can occur before user_exit() is called. This will cause the scheduler
- * to be called when the system is still in usermode.
- *
- * To prevent this, the preempt_enable_notrace will use this function
- * instead of preempt_schedule() to exit user context if needed before
- * calling the scheduler.
- */
-asmlinkage __visible void __sched notrace preempt_schedule_context(void)
-{
- enum ctx_state prev_ctx;
-
- if (likely(!preemptible()))
- return;
-
- /*
- * Need to disable preemption in case user_exit() is traced
- * and the tracer calls preempt_enable_notrace() causing
- * an infinite recursion.
- */
- preempt_disable_notrace();
- prev_ctx = exception_enter();
- preempt_enable_no_resched_notrace();
-
- preempt_schedule();
-
- preempt_disable_notrace();
- exception_exit(prev_ctx);
- preempt_enable_notrace();
-}
-EXPORT_SYMBOL_GPL(preempt_schedule_context);
-#endif /* CONFIG_PREEMPT */
-
/**
* context_tracking_user_exit - Inform the context tracking that the CPU is
* exiting userspace mode and entering the kernel.