'\" t
.\"     Title: preempt_schedule_notrace
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Driver Basics
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "PREEMPT_SCHEDULE_NOT" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Driver Basics"
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.SH "NAME"
preempt_schedule_notrace \- preempt_schedule called by tracing
.SH "SYNOPSIS"
.HP \w'__visible\ void\ __sched\ notrace\ preempt_schedule_notrace('u
.BI "__visible void __sched notrace preempt_schedule_notrace(" "void" ");"
.SH "ARGUMENTS"
.PP
\fIvoid\fR
.RS 4
no arguments
.RE
.SH "DESCRIPTION"
.PP
.PP
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
\fBuser_exit\fR
is called\&. This will cause the scheduler to be called when the system is still in usermode\&.
.PP
To prevent this, the preempt_enable_notrace will use this function instead of
\fBpreempt_schedule\fR
to exit user context if needed before calling the scheduler\&.
.SH "COPYRIGHT"
.br