PREEMPT_SCHEDULE_NOT(9)                   Driver Basics                   PREEMPT_SCHEDULE_NOT(9)



NAME
       preempt_schedule_notrace - preempt_schedule called by tracing

SYNOPSIS
       __visible void __sched notrace preempt_schedule_notrace(void);

ARGUMENTS
       void
           no arguments

DESCRIPTION
       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.

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                   PREEMPT_SCHEDULE_NOT(9)