1.\" Copyright (c) 2018 Jeffrey Roberson 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: stable/12/lib/libc/sys/cpuset_getdomain.2 371948 2022-04-11 01:22:15Z ngie $ 26.\" 27.Dd June 18, 2020 28.Dt CPUSET_GETDOMAIN 2 29.Os 30.Sh NAME 31.Nm cpuset_getdomain , 32.Nm cpuset_setdomain 33.Nd manage memory domain policy 34.Sh LIBRARY 35.Lb libc 36.Sh SYNOPSIS 37.In sys/param.h 38.In sys/domainset.h 39.Ft int 40.Fn cpuset_getdomain "cpulevel_t level" "cpuwhich_t which" "id_t id" "size_t setsize" "domainset_t *mask" "int *policy" 41.Ft int 42.Fn cpuset_setdomain "cpulevel_t level" "cpuwhich_t which" "id_t id" "size_t setsize" "const domainset_t *mask" "int policy" 43.Sh DESCRIPTION 44.Fn cpuset_getdomain 45and 46.Fn cpuset_setdomain 47allow the manipulation of sets of memory domains and allocation policy available 48to processes, threads, jails and other resources. 49These functions may manipulate sets of memory domains that contain many processes 50or per-object anonymous masks that affect only a single object. 51.Pp 52The valid values for the 53.Fa level 54and 55.Fa which 56arguments are documented in 57.Xr cpuset 2 . 58These arguments specify which object and which set of the object we are 59referring to. 60Not all possible combinations are valid. 61For example, only processes may belong to a numbered set accessed by a 62.Fa level 63argument of 64.Dv CPU_LEVEL_CPUSET . 65All resources, however, have a mask which may be manipulated with 66.Dv CPU_LEVEL_WHICH . 67.Pp 68Masks of type 69.Ft domainset_t 70are composed using the 71.Dv DOMAINSET 72macros. 73The kernel tolerates large sets as long as all domains specified 74in the set exist. 75Sets smaller than the kernel uses generate an error on calls to 76.Fn cpuset_getdomain 77even if the result set would fit within the user supplied set. 78Calls to 79.Fn cpuset_setdomain 80tolerate small sets with no restrictions. 81.Pp 82The supplied mask should have a size of 83.Fa setsize 84bytes. 85This size is usually provided by calling 86.Li sizeof(mask) 87which is ultimately determined by the value of 88.Dv DOMAINSET_SETSIZE 89as defined in 90.In sys/domainset.h . 91.Pp 92.Fn cpuset_getdomain 93retrieves the 94mask and policy from the object specified by 95.Fa level , 96.Fa which 97and 98.Fa id 99and stores it in the space provided by 100.Fa mask 101and 102.Fa policy . 103.Pp 104.Fn cpuset_setdomain 105attempts to set the mask and policy for the object specified by 106.Fa level , 107.Fa which 108and 109.Fa id 110to the values in 111.Fa mask 112and 113.Fa policy . 114.Sh ALLOCATION POLICIES 115Valid policy values are as follows: 116.Bl -tag -width "foo" 117.It Dv DOMAINSET_POLICY_ROUNDROBIN 118Memory is allocated on a round-robin basis by cycling through each domain in 119.Fa mask . 120.It Dv DOMAINSET_POLICY_FIRSTTOUCH 121Memory is allocated on the domain local to the CPU the requesting thread is 122running on. Failure to allocate from this domain will fallback to round-robin. 123.It Dv DOMAINSET_POLICY_PREFER 124Memory is allocated preferentially from the single domain specified in the mask. 125If memory is unavailable the domains listed in the parent cpuset will be 126visited in a round-robin order. 127.El 128.Sh RETURN VALUES 129.Rv -std 130.Sh ERRORS 131The following error codes may be set in 132.Va errno : 133.Bl -tag -width Er 134.\" When changing this list, consider updating share/man/man3/pthread_create.3, 135.\" since that function can return any of these errors. 136.It Bq Er EINVAL 137The 138.Fa level 139or 140.Fa which 141argument was not a valid value. 142.It Bq Er EINVAL 143The 144.Fa mask or 145.Fa policy 146argument specified when calling 147.Fn cpuset_setdomain 148was not a valid value. 149.It Bq Er EDEADLK 150The 151.Fn cpuset_setdomain 152call would leave a thread without a valid CPU to run on because the set 153does not overlap with the thread's anonymous mask. 154.It Bq Er EFAULT 155The mask pointer passed was invalid. 156.It Bq Er ESRCH 157The object specified by the 158.Fa id 159and 160.Fa which 161arguments could not be found. 162.It Bq Er ERANGE 163The 164.Fa domainsetsize 165was either preposterously large or smaller than the kernel set size. 166.It Bq Er EPERM 167The calling process did not have the credentials required to complete the 168operation. 169.It Bq Er ECAPMODE 170The calling process attempted to act on a process other than itself, while 171in capability mode. 172See 173.Xr capsicum 4 . 174.El 175.Sh SEE ALSO 176.Xr cpuset 1 , 177.Xr cpuset 2 , 178.Xr cpuset_getaffinity 2 , 179.Xr cpuset_getid 2 , 180.Xr cpuset_setaffinity 2 , 181.Xr cpuset_setid 2 , 182.Xr capsicum 4 , 183.Xr cpuset 9 184.Sh HISTORY 185The 186.Nm 187family of system calls first appeared in 188.Fx 12.0 . 189.Sh AUTHORS 190.An Jeffrey Roberson Aq Mt jeff@FreeBSD.org 191