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diff --git a/man2/mbind.2 b/man2/mbind.2 deleted file mode 100644 index 4b43aca..0000000 --- a/man2/mbind.2 +++ /dev/null @@ -1,503 +0,0 @@ -.\" SPDX-License-Identifier: Linux-man-pages-copyleft-var -.\" -.\" Copyright 2003,2004 Andi Kleen, SuSE Labs. -.\" and Copyright 2007 Lee Schermerhorn, Hewlett Packard -.\" -.\" 2006-02-03, mtk, substantial wording changes and other improvements -.\" 2007-08-27, Lee Schermerhorn <Lee.Schermerhorn@hp.com> -.\" more precise specification of behavior. -.\" -.\" FIXME -.\" Linux 3.8 added MPOL_MF_LAZY, which needs to be documented. -.\" Does it also apply for move_pages()? -.\" -.\" commit b24f53a0bea38b266d219ee651b22dba727c44ae -.\" Author: Lee Schermerhorn <lee.schermerhorn@hp.com> -.\" Date: Thu Oct 25 14:16:32 2012 +0200 -.\" -.TH mbind 2 2023-12-09 "Linux man-pages 6.7" -.SH NAME -mbind \- set memory policy for a memory range -.SH LIBRARY -NUMA (Non-Uniform Memory Access) policy library -.RI ( libnuma ", " \-lnuma ) -.SH SYNOPSIS -.nf -.B "#include <numaif.h>" -.P -.BI "long mbind(void " addr [. len "], unsigned long " len ", int " mode , -.BI " const unsigned long " nodemask [(. maxnode " + ULONG_WIDTH - 1)" -.B " / ULONG_WIDTH]," -.BI " unsigned long " maxnode ", unsigned int " flags ); -.fi -.SH DESCRIPTION -.BR mbind () -sets the NUMA memory policy, -which consists of a policy mode and zero or more nodes, -for the memory range starting with -.I addr -and continuing for -.I len -bytes. -The memory policy defines from which node memory is allocated. -.P -If the memory range specified by the -.IR addr " and " len -arguments includes an "anonymous" region of memory\[em]that is -a region of memory created using the -.BR mmap (2) -system call with the -.BR MAP_ANONYMOUS \[em]or -a memory-mapped file, mapped using the -.BR mmap (2) -system call with the -.B MAP_PRIVATE -flag, pages will be allocated only according to the specified -policy when the application writes (stores) to the page. -For anonymous regions, an initial read access will use a shared -page in the kernel containing all zeros. -For a file mapped with -.BR MAP_PRIVATE , -an initial read access will allocate pages according to the -memory policy of the thread that causes the page to be allocated. -This may not be the thread that called -.BR mbind (). -.P -The specified policy will be ignored for any -.B MAP_SHARED -mappings in the specified memory range. -Rather the pages will be allocated according to the memory policy -of the thread that caused the page to be allocated. -Again, this may not be the thread that called -.BR mbind (). -.P -If the specified memory range includes a shared memory region -created using the -.BR shmget (2) -system call and attached using the -.BR shmat (2) -system call, -pages allocated for the anonymous or shared memory region will -be allocated according to the policy specified, regardless of which -process attached to the shared memory segment causes the allocation. -If, however, the shared memory region was created with the -.B SHM_HUGETLB -flag, -the huge pages will be allocated according to the policy specified -only if the page allocation is caused by the process that calls -.BR mbind () -for that region. -.P -By default, -.BR mbind () -has an effect only for new allocations; if the pages inside -the range have been already touched before setting the policy, -then the policy has no effect. -This default behavior may be overridden by the -.B MPOL_MF_MOVE -and -.B MPOL_MF_MOVE_ALL -flags described below. -.P -The -.I mode -argument must specify one of -.BR MPOL_DEFAULT , -.BR MPOL_BIND , -.BR MPOL_INTERLEAVE , -.BR MPOL_PREFERRED , -or -.B MPOL_LOCAL -(which are described in detail below). -All policy modes except -.B MPOL_DEFAULT -require the caller to specify the node or nodes to which the mode applies, -via the -.I nodemask -argument. -.P -The -.I mode -argument may also include an optional -.IR "mode flag" . -The supported -.I "mode flags" -are: -.TP -.BR MPOL_F_NUMA_BALANCING " (since Linux 5.15)" -.\" commit bda420b985054a3badafef23807c4b4fa38a3dff -.\" commit 6d2aec9e123bb9c49cb5c7fc654f25f81e688e8c -When -.I mode -is -.BR MPOL_BIND , -enable the kernel NUMA balancing for the task if it is supported by the kernel. -If the flag isn't supported by the kernel, or is used with -.I mode -other than -.BR MPOL_BIND , -\-1 is returned and -.I errno -is set to -.BR EINVAL . -.TP -.BR MPOL_F_STATIC_NODES " (since Linux-2.6.26)" -A nonempty -.I nodemask -specifies physical node IDs. -Linux does not remap the -.I nodemask -when the thread moves to a different cpuset context, -nor when the set of nodes allowed by the thread's -current cpuset context changes. -.TP -.BR MPOL_F_RELATIVE_NODES " (since Linux-2.6.26)" -A nonempty -.I nodemask -specifies node IDs that are relative to the set of -node IDs allowed by the thread's current cpuset. -.P -.I nodemask -points to a bit mask of nodes containing up to -.I maxnode -bits. -The bit mask size is rounded to the next multiple of -.IR "sizeof(unsigned long)" , -but the kernel will use bits only up to -.IR maxnode . -A NULL value of -.I nodemask -or a -.I maxnode -value of zero specifies the empty set of nodes. -If the value of -.I maxnode -is zero, -the -.I nodemask -argument is ignored. -Where a -.I nodemask -is required, it must contain at least one node that is on-line, -allowed by the thread's current cpuset context -(unless the -.B MPOL_F_STATIC_NODES -mode flag is specified), -and contains memory. -.P -The -.I mode -argument must include one of the following values: -.TP -.B MPOL_DEFAULT -This mode requests that any nondefault policy be removed, -restoring default behavior. -When applied to a range of memory via -.BR mbind (), -this means to use the thread memory policy, -which may have been set with -.BR set_mempolicy (2). -If the mode of the thread memory policy is also -.BR MPOL_DEFAULT , -the system-wide default policy will be used. -The system-wide default policy allocates -pages on the node of the CPU that triggers the allocation. -For -.BR MPOL_DEFAULT , -the -.I nodemask -and -.I maxnode -arguments must be specify the empty set of nodes. -.TP -.B MPOL_BIND -This mode specifies a strict policy that restricts memory allocation to -the nodes specified in -.IR nodemask . -If -.I nodemask -specifies more than one node, page allocations will come from -the node with sufficient free memory that is closest to -the node where the allocation takes place. -Pages will not be allocated from any node not specified in the -IR nodemask . -(Before Linux 2.6.26, -.\" commit 19770b32609b6bf97a3dece2529089494cbfc549 -page allocations came from -the node with the lowest numeric node ID first, until that node -contained no free memory. -Allocations then came from the node with the next highest -node ID specified in -.I nodemask -and so forth, until none of the specified nodes contained free memory.) -.TP -.B MPOL_INTERLEAVE -This mode specifies that page allocations be interleaved across the -set of nodes specified in -.IR nodemask . -This optimizes for bandwidth instead of latency -by spreading out pages and memory accesses to those pages across -multiple nodes. -To be effective the memory area should be fairly large, -at least 1\ MB or bigger with a fairly uniform access pattern. -Accesses to a single page of the area will still be limited to -the memory bandwidth of a single node. -.TP -.B MPOL_PREFERRED -This mode sets the preferred node for allocation. -The kernel will try to allocate pages from this -node first and fall back to other nodes if the -preferred nodes is low on free memory. -If -.I nodemask -specifies more than one node ID, the first node in the -mask will be selected as the preferred node. -If the -.I nodemask -and -.I maxnode -arguments specify the empty set, then the memory is allocated on -the node of the CPU that triggered the allocation. -.TP -.BR MPOL_LOCAL " (since Linux 3.8)" -.\" commit 479e2802d09f1e18a97262c4c6f8f17ae5884bd8 -.\" commit f2a07f40dbc603c15f8b06e6ec7f768af67b424f -This mode specifies "local allocation"; the memory is allocated on -the node of the CPU that triggered the allocation (the "local node"). -The -.I nodemask -and -.I maxnode -arguments must specify the empty set. -If the "local node" is low on free memory, -the kernel will try to allocate memory from other nodes. -The kernel will allocate memory from the "local node" -whenever memory for this node is available. -If the "local node" is not allowed by the thread's current cpuset context, -the kernel will try to allocate memory from other nodes. -The kernel will allocate memory from the "local node" whenever -it becomes allowed by the thread's current cpuset context. -By contrast, -.B MPOL_DEFAULT -reverts to the memory policy of the thread (which may be set via -.BR set_mempolicy (2)); -that policy may be something other than "local allocation". -.P -If -.B MPOL_MF_STRICT -is passed in -.I flags -and -.I mode -is not -.BR MPOL_DEFAULT , -then the call fails with the error -.B EIO -if the existing pages in the memory range don't follow the policy. -.\" According to the kernel code, the following is not true -.\" --Lee Schermerhorn -.\" In Linux 2.6.16 or later the kernel will also try to move pages -.\" to the requested node with this flag. -.P -If -.B MPOL_MF_MOVE -is specified in -.IR flags , -then the kernel will attempt to move all the existing pages -in the memory range so that they follow the policy. -Pages that are shared with other processes will not be moved. -If -.B MPOL_MF_STRICT -is also specified, then the call fails with the error -.B EIO -if some pages could not be moved. -If the -.B MPOL_INTERLEAVE -policy was specified, -pages already residing on the specified nodes -will not be moved such that they are interleaved. -.P -If -.B MPOL_MF_MOVE_ALL -is passed in -.IR flags , -then the kernel will attempt to move all existing pages in the memory range -regardless of whether other processes use the pages. -The calling thread must be privileged -.RB ( CAP_SYS_NICE ) -to use this flag. -If -.B MPOL_MF_STRICT -is also specified, then the call fails with the error -.B EIO -if some pages could not be moved. -If the -.B MPOL_INTERLEAVE -policy was specified, -pages already residing on the specified nodes -will not be moved such that they are interleaved. -.\" --------------------------------------------------------------- -.SH RETURN VALUE -On success, -.BR mbind () -returns 0; -on error, \-1 is returned and -.I errno -is set to indicate the error. -.\" --------------------------------------------------------------- -.SH ERRORS -.\" I think I got all of the error returns. --Lee Schermerhorn -.TP -.B EFAULT -Part or all of the memory range specified by -.I nodemask -and -.I maxnode -points outside your accessible address space. -Or, there was an unmapped hole in the specified memory range specified by -.I addr -and -.IR len . -.TP -.B EINVAL -An invalid value was specified for -.I flags -or -.IR mode ; -or -.I addr + len -was less than -.IR addr ; -or -.I addr -is not a multiple of the system page size. -Or, -.I mode -is -.B MPOL_DEFAULT -and -.I nodemask -specified a nonempty set; -or -.I mode -is -.B MPOL_BIND -or -.B MPOL_INTERLEAVE -and -.I nodemask -is empty. -Or, -.I maxnode -exceeds a kernel-imposed limit. -.\" As at 2.6.23, this limit is "a page worth of bits", e.g., -.\" 8 * 4096 bits, assuming a 4kB page size. -Or, -.I nodemask -specifies one or more node IDs that are -greater than the maximum supported node ID. -Or, none of the node IDs specified by -.I nodemask -are on-line and allowed by the thread's current cpuset context, -or none of the specified nodes contain memory. -Or, the -.I mode -argument specified both -.B MPOL_F_STATIC_NODES -and -.BR MPOL_F_RELATIVE_NODES . -.TP -.B EIO -.B MPOL_MF_STRICT -was specified and an existing page was already on a node -that does not follow the policy; -or -.B MPOL_MF_MOVE -or -.B MPOL_MF_MOVE_ALL -was specified and the kernel was unable to move all existing -pages in the range. -.TP -.B ENOMEM -Insufficient kernel memory was available. -.TP -.B EPERM -The -.I flags -argument included the -.B MPOL_MF_MOVE_ALL -flag and the caller does not have the -.B CAP_SYS_NICE -privilege. -.\" --------------------------------------------------------------- -.SH STANDARDS -Linux. -.SH HISTORY -Linux 2.6.7. -.P -Support for huge page policy was added with Linux 2.6.16. -For interleave policy to be effective on huge page mappings the -policied memory needs to be tens of megabytes or larger. -.P -Before Linux 5.7. -.\" commit dcf1763546d76c372f3136c8d6b2b6e77f140cf0 -.B MPOL_MF_STRICT -was ignored on huge page mappings. -.P -.B MPOL_MF_MOVE -and -.B MPOL_MF_MOVE_ALL -are available only on Linux 2.6.16 and later. -.SH NOTES -For information on library support, see -.BR numa (7). -.P -NUMA policy is not supported on a memory-mapped file range -that was mapped with the -.B MAP_SHARED -flag. -.P -The -.B MPOL_DEFAULT -mode can have different effects for -.BR mbind () -and -.BR set_mempolicy (2). -When -.B MPOL_DEFAULT -is specified for -.BR set_mempolicy (2), -the thread's memory policy reverts to the system default policy -or local allocation. -When -.B MPOL_DEFAULT -is specified for a range of memory using -.BR mbind (), -any pages subsequently allocated for that range will use -the thread's memory policy, as set by -.BR set_mempolicy (2). -This effectively removes the explicit policy from the -specified range, "falling back" to a possibly nondefault -policy. -To select explicit "local allocation" for a memory range, -specify a -.I mode -of -.B MPOL_LOCAL -or -.B MPOL_PREFERRED -with an empty set of nodes. -This method will work for -.BR set_mempolicy (2), -as well. -.SH SEE ALSO -.BR get_mempolicy (2), -.BR getcpu (2), -.BR mmap (2), -.BR set_mempolicy (2), -.BR shmat (2), -.BR shmget (2), -.BR numa (3), -.BR cpuset (7), -.BR numa (7), -.BR numactl (8) |