'\" t
.\"     Title: futex_proxy_trylock_atomic
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Futex API reference
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "FUTEX_PROXY_TRYLOCK_" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Futex API reference"
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.SH "NAME"
futex_proxy_trylock_atomic \- Attempt an atomic lock for the top waiter
.SH "SYNOPSIS"
.HP \w'int\ futex_proxy_trylock_atomic('u
.BI "int futex_proxy_trylock_atomic(u32\ __user\ *\ " "pifutex" ", struct\ futex_hash_bucket\ *\ " "hb1" ", struct\ futex_hash_bucket\ *\ " "hb2" ", union\ futex_key\ *\ " "key1" ", union\ futex_key\ *\ " "key2" ", struct\ futex_pi_state\ **\ " "ps" ", int\ " "set_waiters" ");"
.SH "ARGUMENTS"
.PP
\fIpifutex\fR
.RS 4
the user address of the to futex
.RE
.PP
\fIhb1\fR
.RS 4
the from futex hash bucket, must be locked by the caller
.RE
.PP
\fIhb2\fR
.RS 4
the to futex hash bucket, must be locked by the caller
.RE
.PP
\fIkey1\fR
.RS 4
the from futex key
.RE
.PP
\fIkey2\fR
.RS 4
the to futex key
.RE
.PP
\fIps\fR
.RS 4
address to store the pi_state pointer
.RE
.PP
\fIset_waiters\fR
.RS 4
force setting the FUTEX_WAITERS bit (1) or not (0)
.RE
.SH "DESCRIPTION"
.PP
Try and get the lock on behalf of the top waiter if we can do it atomically\&. Wake the top waiter if we succeed\&. If the caller specified set_waiters, then direct
\fBfutex_lock_pi_atomic\fR
to force setting the FUTEX_WAITERS bit\&. hb1 and hb2 must be held by the caller\&.
.SH "RETURN"
.PP
0 \- failed to acquire the lock atomically; >0 \- acquired the lock, return value is vpid of the top_waiter <0 \- error
.SH "AUTHOR"
.PP
\fBRusty Russell\fR <\&rusty@rustcorp.com.au\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br