'\" t
.\"     Title: round_jiffies
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: May 2018
.\"    Manual: Driver Basics
.\"    Source: Kernel Hackers Manual 3.16.56
.\"  Language: English
.\"
.TH "ROUND_JIFFIES" "9" "May 2018" "Kernel Hackers Manual 3\&.16\&" "Driver Basics"
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.SH "NAME"
round_jiffies \- function to round jiffies to a full second
.SH "SYNOPSIS"
.HP \w'unsigned\ long\ round_jiffies('u
.BI "unsigned long round_jiffies(unsigned\ long\ " "j" ");"
.SH "ARGUMENTS"
.PP
\fIj\fR
.RS 4
the time in (absolute) jiffies that should be rounded
.RE
.SH "DESCRIPTION"
.PP
\fBround_jiffies\fR
rounds an absolute time in the future (in jiffies) up or down to (approximately) full seconds\&. This is useful for timers for which the exact time they fire does not matter too much, as long as they fire approximately every X seconds\&.
.PP
By rounding these timers to whole seconds, all such timers will fire at the same time, rather than at various times spread out\&. The goal of this is to have the CPU wake up less, which saves power\&.
.PP
The return value is the rounded version of the
\fIj\fR
parameter\&.
.SH "COPYRIGHT"
.br