diff options
Diffstat (limited to 'share/man/man3/pthread_affinity_np.3')
-rw-r--r-- | share/man/man3/pthread_affinity_np.3 | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/share/man/man3/pthread_affinity_np.3 b/share/man/man3/pthread_affinity_np.3 new file mode 100644 index 000000000000..5f867f996128 --- /dev/null +++ b/share/man/man3/pthread_affinity_np.3 @@ -0,0 +1,153 @@ +.\"- +.\" 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 Mt davidxu@FreeBSD.org , +and this manpage was written by +.An Xin LI Aq Mt delphij@FreeBSD.org . |