'\" t
.\"     Title: clear_bit
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: April 2019
.\"    Manual: Basic C Library Functions
.\"    Source: Kernel Hackers Manual 4.9.168
.\"  Language: English
.\"
.TH "CLEAR_BIT" "9" "April 2019" "Kernel Hackers Manual 4\&.9\&." "Basic C Library Functions"
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.SH "NAME"
clear_bit \- Clears a bit in memory
.SH "SYNOPSIS"
.HP \w'void\ clear_bit('u
.BI "void clear_bit(long\ " "nr" ", volatile\ unsigned\ long\ *\ " "addr" ");"
.SH "ARGUMENTS"
.PP
\fInr\fR
.RS 4
Bit to clear
.RE
.PP
\fIaddr\fR
.RS 4
Address to start counting from
.RE
.SH "DESCRIPTION"
.PP
\fBclear_bit\fR
is atomic and may not be reordered\&. However, it does not contain a memory barrier, so if it is used for locking purposes, you should call
\fBsmp_mb__before_atomic\fR
and/or
\fBsmp_mb__after_atomic\fR
in order to ensure changes are visible on other processors\&.
.SH "COPYRIGHT"
.br