.TH "clear_bit" 9 "clear_bit" "25 May 1998" "Kernel Hacker's Manual" LINUX
.SH NAME
clear_bit \-  Clears a bit in memory
.SH SYNOPSIS
.B "void" clear_bit
.BI "(int " nr ","
.BI "volatile void *" addr ");"
.SH ARGUMENTS
.IP "nr" 12
 Bit to clear
.IP "addr" 12
 Address to start counting from
.SH "DESCRIPTION"
\fBclear_bit\fP 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_clear_bit\fP and/or \fBsmp_mb__after_clear_bit\fP
in order to ensure changes are visible on other processors.