156 lines
4.2 KiB
Groff
156 lines
4.2 KiB
Groff
.\"-
|
|
.\" Copyright (c) 2010 Xin LI <delphij@FreeBSD.org>
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd March 23, 2010
|
|
.Dt PTHREAD_AFFINITY_NP 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm pthread_getaffinity_np ,
|
|
.Nm pthread_setaffinity_np
|
|
.Nd manage CPU affinity
|
|
.Sh LIBRARY
|
|
.Lb libpthread
|
|
.Sh SYNOPSIS
|
|
.In pthread_np.h
|
|
.Ft int
|
|
.Fn pthread_getaffinity_np "pthread_t td" "size_t cpusetsize" "cpuset_t *cpusetp"
|
|
.Ft int
|
|
.Fn pthread_setaffinity_np "pthread_t td" "size_t cpusetsize" "const cpuset_t *cpusetp"
|
|
.Sh DESCRIPTION
|
|
.Fn pthread_getaffinity_np
|
|
and
|
|
.Fn pthread_setaffinity_np
|
|
allow the manipulation of sets of CPUs available to the specified thread.
|
|
.Pp
|
|
Masks of type
|
|
.Ft cpuset_t
|
|
are composed using the
|
|
.Dv CPU_SET
|
|
macros.
|
|
The kernel tolerates large sets as long as all CPUs specified
|
|
in the set exist.
|
|
Sets smaller than the kernel uses generate an error on calls to
|
|
.Fn pthread_getaffinity_np
|
|
even if the result set would fit within the user supplied set.
|
|
Calls to
|
|
.Fn pthread_setaffinity_np
|
|
tolerate small sets with no restrictions.
|
|
.Pp
|
|
The supplied mask should have a size of
|
|
.Fa cpusetsize
|
|
bytes.
|
|
This size is usually provided by calling
|
|
.Li sizeof(cpuset_t)
|
|
which is ultimately determined by the value of
|
|
.Dv CPU_SETSIZE
|
|
as defined in
|
|
.In sys/cpuset.h .
|
|
.Pp
|
|
.Fn pthread_getaffinity_np
|
|
retrieves the
|
|
mask from the thread specified by
|
|
.Fa td ,
|
|
and stores it in the space provided by
|
|
.Fa cpusetp .
|
|
.Pp
|
|
.Fn pthread_setaffinity_np
|
|
attempts to set the mask for the thread specified by
|
|
.Fa td
|
|
to the value in
|
|
.Fa cpusetp .
|
|
.Sh RETURN VALUES
|
|
If successful, the
|
|
.Fn pthread_getaffinity_np
|
|
and
|
|
.Fn pthread_setaffinity_np
|
|
functions will return zero.
|
|
Otherwise an error number will be returned
|
|
to indicate the error.
|
|
.Sh ERRORS
|
|
The
|
|
.Fn pthread_getaffinity_np
|
|
and
|
|
.Fn pthread_setaffinity_np
|
|
functions may fail if:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EDEADLK
|
|
The
|
|
.Fn pthread_setaffinity_np
|
|
call would leave a thread without a valid CPU to run on because the set
|
|
does not overlap with the thread's anonymous mask.
|
|
.It Bq Er EFAULT
|
|
The
|
|
.Fa cpusetp
|
|
pointer passed was invalid.
|
|
.It Bq Er ESRCH
|
|
The thread specified by the
|
|
.Fa td
|
|
argument could not be found.
|
|
.It Bq Er ERANGE
|
|
The
|
|
.Fa cpusetsize
|
|
was either preposterously large or smaller than the kernel set size.
|
|
.It Bq Er EPERM
|
|
The calling thread did not have the credentials required to complete the
|
|
operation.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr cpuset 1 ,
|
|
.Xr cpuset 2 ,
|
|
.Xr cpuset_getid 2 ,
|
|
.Xr cpuset_setid 2 ,
|
|
.Xr pthread 3 ,
|
|
.Xr pthread_attr_getaffinity_np 3 ,
|
|
.Xr pthread_attr_setaffinity_np 3
|
|
.Sh STANDARDS
|
|
The
|
|
.Nm pthread_getaffinity_np
|
|
and
|
|
.Nm pthread_setaffinity_np
|
|
functions are non-standard
|
|
.Fx
|
|
extensions and may be not available on other operating systems.
|
|
.Sh HISTORY
|
|
The
|
|
.Nm pthread_getaffinity_np
|
|
and
|
|
.Nm pthread_setaffinity_np
|
|
function first appeared in
|
|
.Fx 7.2 .
|
|
.Sh AUTHORS
|
|
.An -nosplit
|
|
The
|
|
.Nm pthread_getaffinity_np
|
|
and
|
|
.Nm pthread_setaffinity_np
|
|
functions were written by
|
|
.An David Xu
|
|
.Aq davidxu@FreeBSD.org ,
|
|
and this manpage was written by
|
|
.An Xin LI
|
|
.Aq delphij@FreeBSD.org .
|