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diff --git a/upstream/opensuse-leap-15-6/man2/migrate_pages.2 b/upstream/opensuse-leap-15-6/man2/migrate_pages.2 new file mode 100644 index 00000000..fd6c922b --- /dev/null +++ b/upstream/opensuse-leap-15-6/man2/migrate_pages.2 @@ -0,0 +1,183 @@ +.\" Copyright 2009 Intel Corporation +.\" Author: Andi Kleen +.\" Based on the move_pages manpage which was +.\" This manpage is Copyright (C) 2006 Silicon Graphics, Inc. +.\" Christoph Lameter +.\" +.\" %%%LICENSE_START(VERBATIM_TWO_PARA) +.\" Permission is granted to make and distribute verbatim copies of this +.\" manual provided the copyright notice and this permission notice are +.\" preserved on all copies. +.\" +.\" Permission is granted to copy and distribute modified versions of this +.\" manual under the conditions for verbatim copying, provided that the +.\" entire resulting derived work is distributed under the terms of a +.\" permission notice identical to this one. +.\" %%%LICENSE_END +.\" +.TH migrate_pages 2 2023-03-30 "Linux man-pages 6.04" +.SH NAME +migrate_pages \- move all pages in a process to another set of nodes +.SH LIBRARY +NUMA (Non-Uniform Memory Access) policy library +.RI ( libnuma ", " \-lnuma ) +.SH SYNOPSIS +.nf +.B #include <numaif.h> +.PP +.BI "long migrate_pages(int " pid ", unsigned long " maxnode, +.BI " const unsigned long *" old_nodes, +.BI " const unsigned long *" new_nodes ); +.fi +.SH DESCRIPTION +.BR migrate_pages () +attempts to move all pages of the process +.I pid +that are in memory nodes +.I old_nodes +to the memory nodes in +.IR new_nodes . +Pages not located in any node in +.I old_nodes +will not be migrated. +As far as possible, +the kernel maintains the relative topology relationship inside +.I old_nodes +during the migration to +.IR new_nodes . +.PP +The +.I old_nodes +and +.I new_nodes +arguments are pointers to bit masks of node numbers, with up to +.I maxnode +bits in each mask. +These masks are maintained as arrays of unsigned +.I long +integers (in the last +.I long +integer, the bits beyond those specified by +.I maxnode +are ignored). +The +.I maxnode +argument is the maximum node number in the bit mask plus one (this is the same +as in +.BR mbind (2), +but different from +.BR select (2)). +.PP +The +.I pid +argument is the ID of the process whose pages are to be moved. +To move pages in another process, +the caller must be privileged +.RB ( CAP_SYS_NICE ) +or the real or effective user ID of the calling process must match the +real or saved-set user ID of the target process. +If +.I pid +is 0, then +.BR migrate_pages () +moves pages of the calling process. +.PP +Pages shared with another process will be moved only if the initiating +process has the +.B CAP_SYS_NICE +privilege. +.SH RETURN VALUE +On success +.BR migrate_pages () +returns the number of pages that could not be moved +(i.e., a return of zero means that all pages were successfully moved). +On error, it returns \-1, and sets +.I errno +to indicate the error. +.SH ERRORS +.TP +.B EFAULT +Part or all of the memory range specified by +.IR old_nodes / new_nodes +and +.I maxnode +points outside your accessible address space. +.TP +.B EINVAL +The value specified by +.I maxnode +exceeds a kernel-imposed limit. +.\" As at 3.5, this limit is "a page worth of bits", e.g., +.\" 8 * 4096 bits, assuming a 4kB page size. +Or, +.I old_nodes +or +.I new_nodes +specifies one or more node IDs that are +greater than the maximum supported node ID. +Or, none of the node IDs specified by +.I new_nodes +are on-line and allowed by the process's current cpuset context, +or none of the specified nodes contain memory. +.TP +.B EPERM +Insufficient privilege +.RB ( CAP_SYS_NICE ) +to move pages of the process specified by +.IR pid , +or insufficient privilege +.RB ( CAP_SYS_NICE ) +to access the specified target nodes. +.TP +.B ESRCH +No process matching +.I pid +could be found. +.\" FIXME Document the other errors that can occur for migrate_pages() +.SH STANDARDS +Linux. +.SH HISTORY +Linux 2.6.16. +.SH NOTES +For information on library support, see +.BR numa (7). +.PP +Use +.BR get_mempolicy (2) +with the +.B MPOL_F_MEMS_ALLOWED +flag to obtain the set of nodes that are allowed by +the calling process's cpuset. +Note that this information is subject to change at any +time by manual or automatic reconfiguration of the cpuset. +.PP +Use of +.BR migrate_pages () +may result in pages whose location +(node) violates the memory policy established for the +specified addresses (see +.BR mbind (2)) +and/or the specified process (see +.BR set_mempolicy (2)). +That is, memory policy does not constrain the destination +nodes used by +.BR migrate_pages (). +.PP +The +.I <numaif.h> +header is not included with glibc, but requires installing +.I libnuma\-devel +or a similar package. +.SH SEE ALSO +.BR get_mempolicy (2), +.BR mbind (2), +.BR set_mempolicy (2), +.BR numa (3), +.BR numa_maps (5), +.BR cpuset (7), +.BR numa (7), +.BR migratepages (8), +.BR numastat (8) +.PP +.I Documentation/vm/page_migration.rst +in the Linux kernel source tree |