'\" t
.\"     Title: usleep_range
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Driver Basics
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "USLEEP_RANGE" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Driver Basics"
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.SH "NAME"
usleep_range \- Sleep for an approximate time
.SH "SYNOPSIS"
.HP \w'void\ __sched\ usleep_range('u
.BI "void __sched usleep_range(unsigned\ long\ " "min" ", unsigned\ long\ " "max" ");"
.SH "ARGUMENTS"
.PP
\fImin\fR
.RS 4
Minimum time in usecs to sleep
.RE
.PP
\fImax\fR
.RS 4
Maximum time in usecs to sleep
.RE
.SH "DESCRIPTION"
.PP
In non\-atomic context where the exact wakeup time is flexible, use
\fBusleep_range\fR
instead of
\fBudelay\fR\&. The sleep improves responsiveness by avoiding the CPU\-hogging busy\-wait of
\fBudelay\fR, and the range reduces power usage by allowing hrtimers to take advantage of an already\- scheduled interrupt instead of scheduling a new one just for this sleep\&.
.SH "COPYRIGHT"
.br