1 .\" Copyright (c) 2008 Christian Brueffer
2 .\" Copyright (c) 2008 Jeffrey Roberson
3 .\" All rights reserved.
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28 .Dd September 10, 2010
32 .Nm cpuset_getaffinity ,
33 .Nm cpuset_setaffinity
34 .Nd manage CPU affinity
41 .Fn cpuset_getaffinity "cpulevel_t level" "cpuwhich_t which" "id_t id" "size_t setsize" "cpuset_t *mask"
43 .Fn cpuset_setaffinity "cpulevel_t level" "cpuwhich_t which" "id_t id" "size_t setsize" "const cpuset_t *mask"
45 .Fn cpuset_getaffinity
47 .Fn cpuset_setaffinity
48 allow the manipulation of sets of CPUs available to processes, threads,
49 interrupts, jails and other resources.
50 These functions may manipulate sets of CPUs that contain many processes
51 or per-object anonymous masks that effect only a single object.
53 The valid values for the
57 arguments are documented in
59 These arguments specify which object and which set of the object we are
61 Not all possible combinations are valid.
62 For example, only processes may belong to a numbered set accessed by a
65 .Dv CPU_LEVEL_CPUSET .
66 All resources, however, have a mask which may be manipulated with
71 are composed using the
74 The kernel tolerates large sets as long as all CPUs specified
76 Sets smaller than the kernel uses generate an error on calls to
77 .Fn cpuset_getaffinity
78 even if the result set would fit within the user supplied set.
80 .Fn cpuset_setaffinity
81 tolerate small sets with no restrictions.
83 The supplied mask should have a size of
86 This size is usually provided by calling
88 which is ultimately determined by the value of
93 .Fn cpuset_getaffinity
95 mask from the object specified by
100 and stores it in the space provided by
103 .Fn cpuset_setaffinity
104 attempts to set the mask for the object specified by
114 The following error codes may be set in
122 argument was not a valid value.
126 argument specified when calling
127 .Fn cpuset_setaffinity
128 was not a valid value.
131 .Fn cpuset_setaffinity
132 call would leave a thread without a valid CPU to run on because the set
133 does not overlap with the thread's anonymous mask.
135 The mask pointer passed was invalid.
137 The object specified by the
141 arguments could not be found.
145 was either preposterously large or smaller than the kernel set size.
147 The calling process did not have the credentials required to complete the
156 .Xr pthread_affinity_np 3 ,
157 .Xr pthread_attr_affinity_np 3
161 family of system calls first appeared in
164 .An Jeffrey Roberson Aq jeff@FreeBSD.org