.\" $NetBSD: kcpuset.9,v 1.9 2014/03/18 18:20:40 riastradh Exp $ */ .\" .\" Copyright (c) 2011 Jukka Ruohonen <jruohonen.iki.fi> .\" 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. .\" .Dd July 17, 2013 .Dt KCPUSET 9 .Os .Sh NAME .Nm kcpuset , .Nm kcpuset_create , .Nm kcpuset_destroy , .Nm kcpuset_clone , .Nm kcpuset_copy , .Nm kcpuset_use , .Nm kcpuset_unuse , .Nm kcpuset_copyin , .Nm kcpuset_copyout , .Nm kcpuset_zero , .Nm kcpuset_fill , .Nm kcpuset_set , .Nm kcpuset_clear , .Nm kcpuset_isset , .Nm kcpuset_isotherset , .Nm kcpuset_iszero , .Nm kcpuset_match , .Nm kcpuset_intersect , .Nm kcpuset_merge , .Nm kcpuset_remove , .Nm kcpuset_ffs , .Nm kcpuset_ffs_intersecting , .Nm kcpuset_countset , .Nm kcpuset_atomic_set , .Nm kcpuset_atomic_clear , .Nm kcpuset_atomicly_intersect , .Nm kcpuset_atomicly_merge , .Nm kcpuset_atomicly_remove , .Nm kcpuset_export_32 .Nd dynamic kernel CPU sets .Sh SYNOPSIS .In sys/kcpuset.h .Ft void .Fn kcpuset_create "kcpuset_t **retkcp" "bool zero" .Ft void .Fn kcpuset_destroy "kcpuset_t *kcp" .Ft void .Fn kcpuset_clone "kcpuset_t **retkcp" "const kcpuset_t *skcp" .Ft void .Fn kcpuset_copy "kcpuset_t *dkcp" "const kcpuset_t *skcp" .Ft void .Fn kcpuset_use "kcpuset_t *kcp" .Ft void .Fn kcpuset_unuse "kcpuset_t *kcp" "kcpuset_t **lst" .Ft int .Fn kcpuset_copyin "const cpuset_t *ucp" "kcpuset_t *kcp" "size_t len" .Ft int .Fn kcpuset_copyout "kcpuset_t *kcp" "cpuset_t *ucp" "size_t len" .Ft void .Fn kcpuset_zero "kcpuset_t *kcp" .Ft void .Fn kcpuset_fill "kcpuset_t *kcp" .Ft void .Fn kcpuset_set "kcpuset_t *kcp" "cpuid_t cpu" .Ft void .Fn kcpuset_clear "kcpuset_t *kcp" "cpuid_t cpu" .Ft bool .Fn kcpuset_isset "const kcpuset_t * kcp" "cpuid_t cpu" .Ft bool .Fn kcpuset_isotherset "const kcpuset_t * kcp" "cpuid_t cpu" .Ft bool .Fn kcpuset_iszero "const kcpuset_t *kcp" .Ft bool .Fn kcpuset_intersecting_p "const kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft bool .Fn kcpuset_match "const kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_intersect "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_merge "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_remove "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft cpuid_t .Fn kcpuset_ffs "const kcpuset_t *kcp" .Ft cpuid_t .Fn kcpuset_ffs_intersecting "const kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft int .Fn kcpuset_countset "const kcpuset_t *kcp" .Ft void .Fn kcpuset_atomic_set "kcpuset_t *kcp" "cpuid_t cpu" .Ft void .Fn kcpuset_atomic_clear "kcpuset_t *kcp" "cpuid_t cpu" .Ft void .Fn kcpuset_atomicly_intersect "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_atomicly_merge "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_atomicly_remove "kcpuset_t *kcp1" "const kcpuset_t *kcp2" .Ft void .Fn kcpuset_export_u32 "const kcpuset_t *kcp" "uint32_t *bitfield" "size_t len" .Sh DESCRIPTION The machine-independent .Nm subsystem provides support for dynamic processor sets. Conceptually .Nm can be understood to be the kernel equivalent of the user space .Xr cpuset 3 interface. .Sh FUNCTIONS .Bl -tag -width compact .It Fn kcpuset_create "retkcp" "zero" The .Fn kcpuset_create function creates a dynamic .Tn CPU set and stores the result to .Fa retkcp . If the boolean .Fa zero is not false, the allocated set is also initialized to zero. .It Fn kcpuset_destroy "kcp" Destroys the .Tn CPU set .Fa kcp and schedules any linked CPU sets for deferred destruction. .It Fn kcpuset_copy "dkcp" "skcp" Copies the .Tn CPU set pointed by .Fa skcp to .Fa dkcp . .It Fn kcpuset_clone "retkcp" "skcp" Creates a dynamic .Tn CPU set and stores the result to .Fa retkcp and copies the .Tn CPU set pointed by .Fa skcp to the new .Tn CPU set. .It Fn kcpuset_use "kcp" Marks .Fa kcp as being in use by increasing the reference count of the object. Note that initially .Fn kcpuset_create sets the reference count to 1. .It Fn kcpuset_unuse "kcp" "lst" Decreases the internal reference count of .Fa kcp , and on the last reference (when the count reaches zero), destroys .Fa kcp . If .Fa lst is not .Dv NULL , then instead of destroying, .Fa kcp will be added to the .Fa lst list for a deferred destruction. .It Fn kcpuset_copyin "ucp" "kcp" "len" Copies the .Fa len bytes long user-space .Tn CPU set .Fa ucp to the kernel .Tn CPU set .Fa kcp . .It Fn kcpuset_copyout "kcp" "ucp" "len" Copies the kernel .Tn CPU set .Fa kcp to the user-space .Tn CPU set .Fa ucp . .It Fn kcpuset_zero "kcp" Clears the set .Fa kcp . .It Fn kcpuset_fill "kcp" Fills the whole set .Fa kcp with ones. .It Fn kcpuset_set "kcp" "cpu" Adds .Fa cpu to the set .Fa kcp . .It Fn kcpuset_clear "kcp" "cpu" Removes .Fa cpu from the set .Fa kcp . .It Fn kcpuset_isset "kcp" "cpu" Returns true if .Fa cpu is part of the .Tn CPU set .Fa kcp . .It Fn kcpuset_isotherset "kcp" "cpu" Returns true if there any CPUs other than .Fa cpu in the .Tn CPU set .Fa kcp . .It Fn kcpuset_iszero "kcp" Returns true if the set .Fa kcp is empty. .It Fn kcpuset_match "kcp1" "kcp2" Compares the sets .Fa kcp1 and .Fa kcp2 , returning true if these are identical. .It Fn kcpuset_intersect "kcp1" "kcp2" Removes any .Tn CPU not set in .Fa kcp2 from the set .Fa kcp1 . .It Fn kcpuset_merge "kcp1" "kcp2" Merges the set .Fa kcp2 to the set .Fa kcp1 . .It Fn kcpuset_remove "kcp1" "kcp2" Removes any .Tn CPU present in .Fa kcp2 from the set .Fa kcp1 . .It Fn kcpuset_ffs "kcp" Returns the lowest numbered .Ft cpu present in .Fa kcp plus 1. If .Fa kcp is empty, a value of 0 is returned. .Fa kcp .It Fn kcpuset_ffs_intersecting "kcp1" "kcp2" Returns the lowest numbered .Ft cpu present in the intersection of .Fa kcp1 and .Fa kcp2 plus 1. If the intersection is empty, a value of 0 is returned. .It Fn kcpuset_countset "kcp" Counts how many CPUs are in the set .Fa kcp . .It Fn kcpuset_atomic_set "kcp" "cpu" The .Fn kcpuset_atomic_set function operates as .Fn kcpuset_set , but the operation is atomic; see .Xr atomic_ops 3 for more details. .It Fn kcpuset_atomic_clear "kcp" "cpu" Removes .Fa cpu from the .Tn CPU set .Fa kcp atomically. .It Fn kcpuset_atomicly_intersect "kcp1" "kcp2" The .Fn kcpuset_atomicly_intersect function operates as .Fn kcpuset_intersect , but the operation is performed using atomic operations; see .Xr atomic_ops 3 for more details. .It Fn kcpuset_atomicly_merge "kcp1" "kcp2" The .Fn kcpuset_atomicly_merge function operates as .Fn kcpuset_merge , but the operation is performed using atomic operations; see .Xr atomic_ops 3 for more details. .It Fn kcpuset_atomicly_remove "kcp1" "kcp2" The .Fn kcpuset_atomicly_remove function operates as .Fn kcpuset_remove , but the operation is performed using atomic operations; see .Xr atomic_ops 3 for more details. .It Fn kcpuset_export_u32 "kcp" "bitfield" "len" Exports the CPU set .Fa kcp into a format of 32-bit integer array, specified by .Fa bitfield and length in bytes by .Fa len . An integers is in the host byte-order and represents a bit field. The first bit at index zero represents CPU number 0, and so on. .El .Sh CODE REFERENCES The .Nm subsystem is implemented within .Pa sys/kern/subr_kcpuset.c . .Sh SEE ALSO .Xr cpuset 3 .Sh HISTORY The .Nm subsystem first appeared in .Nx 6.0 .