'\" t
.\"     Title: list_empty_careful
.\"    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: Data Types
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "LIST_EMPTY_CAREFUL" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Data Types"
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.SH "NAME"
list_empty_careful \- tests whether a list is empty and not being modified
.SH "SYNOPSIS"
.HP \w'int\ list_empty_careful('u
.BI "int list_empty_careful(const\ struct\ list_head\ *\ " "head" ");"
.SH "ARGUMENTS"
.PP
\fIhead\fR
.RS 4
the list to test
.RE
.SH "DESCRIPTION"
.PP
tests whether a list is empty _and_ checks that no other CPU might be in the process of modifying either member (next or prev)
.SH "NOTE"
.PP
using
\fBlist_empty_careful\fR
without synchronization can only be safe if the only activity that can happen to the list entry is
\fBlist_del_init\fR\&. Eg\&. it cannot be used if another CPU could re\-\fBlist_add\fR
it\&.
.SH "COPYRIGHT"
.br