[linuxjm/LDP_man-pages.git] / draft / man2 / get_mempolicy.2

.\" Copyright 2003,2004 Andi Kleen, SuSE Labs.
.\" and Copyright 2007 Lee Schermerhorn, Hewlett Packard
.\"
.\" 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.
.\"
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\"
.\" 2006-02-03, mtk, substantial wording changes and other improvements
.\" 2007-08-27, Lee Schermerhorn <Lee.Schermerhorn@hp.com>
.\"     more precise specification of behavior.
.\"
.\" Japanese Version Copyright (c) 2006 Akihiro MOTOKI
.\"         all rights reserved.
.\" Translated 2006-08-14, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.39
.\" Updated 2008-02-13, Akihiro MOTOKI, LDP v2.77
.\" Updated 2008-08-06, Akihiro MOTOKI, LDP v3.05
.\" Updated 2008-08-21, Akihiro MOTOKI, LDP v3.07
.\" Updated 2008-11-19, Akihiro MOTOKI, LDP v3.13
.\"
.TH GET_MEMPOLICY 2 2008-08-15 Linux "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O get_mempolicy \- Retrieve NUMA memory policy for a process
get_mempolicy \- ¥×¥í¥»¥¹¤Î NUMA ¥á¥â¥ê¤Î¥Ý¥ê¥·¡¼¤ò¼èÆÀ¤¹¤ë
.\"O .SH SYNOPSIS
.SH ½ñ¼°
.nf
.B "#include <numaif.h>"
.sp
.BI "int get_mempolicy(int *" mode ", unsigned long *" nodemask ,
.BI "                  unsigned long " maxnode ", unsigned long " addr ,
.BI "                  unsigned long " flags );
.sp
.\"O Link with \fI\-lnuma\fP.
\fI\-lnuma\fP ¤Ç¥ê¥ó¥¯¤¹¤ë¡£
.fi
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O .BR get_mempolicy ()
.\"O retrieves the NUMA policy of the calling process or of a memory address,
.\"O depending on the setting of
.\"O .IR flags .
.BR get_mempolicy ()
¤Ï¡¢¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤â¤·¤¯¤Ï»ØÄꤵ¤ì¤¿¥á¥â¥ê¥¢¥É¥ì¥¹¤Î
NUMA ¥Ý¥ê¥·¡¼¤ò
.I flags
¤ÎÀßÄê¤Ë½¾¤Ã¤Æ¼èÆÀ¤¹¤ë¡£

.\"O A NUMA machine has different
.\"O memory controllers with different distances to specific CPUs.
.\"O The memory policy defines from which node memory is allocated for
.\"O the process.
NUMA (ÈóÂоΥá¥â¥ê¥¢¥¯¥»¥¹) ¥Þ¥·¥ó¤Ç¤Ï¡¢CPU ¤Ë¤è¤ê
¥á¥â¥ê¥³¥ó¥È¥í¡¼¥é¤¬°Û¤Ê¤ê¡¢µ÷Î¥¤â°Û¤Ê¤Ã¤Æ¤¤¤ë¡£
¥á¥â¥ê¥Ý¥ê¥·¡¼¤Ï¡¢¤É¤Î¥Î¡¼¥É¤«¤é¥á¥â¥ê¤ò¤½¤Î¥×¥í¥»¥¹¤Ë
³ä¤êÅö¤Æ¤ë¤«¤òÄê¤á¤ë¤â¤Î¤Ç¤¢¤ë¡£

.\"O If
.\"O .I flags
.\"O is specified as 0,
.\"O then information about the calling process's default policy
.\"O (as set by
.\"O .BR set_mempolicy (2))
.\"O is returned.
.I flags
¤Ë 0 ¤¬»ØÄꤵ¤ì¤¿¾ì¹ç¡¢
.RB ( set_mempolicy (2)
¤ÇÀßÄꤵ¤ì¤¿)
¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î¥Ç¥Õ¥©¥ë¥È¥Ý¥ê¥·¡¼¤Ë´Ø¤¹¤ë¾ðÊó¤òÊÖ¤¹¡£
.\"O The policy returned
.\"O .RI [ mode
.\"O and
.\"O .IR nodemask ]
.\"O may be used to restore the process's policy to its state at
.\"O the time of the call to
.\"O .BR get_mempolicy ()
.\"O using
.\"O .BR set_mempolicy (2).
ÊÖ¤µ¤ì¤¿¥Ý¥ê¥·¡¼
.RI [ mode
¤È
.IR nodemask ]
¤ò
.BR set_mempolicy (2)
¤ËÅϤ¹¤³¤È¤Ç¡¢¤½¤Î¥×¥í¥»¥¹¤Î¥Ý¥ê¥·¡¼¤ò
.BR get_mempolicy ()
¤ò¸Æ¤Ó½Ð¤·¤¿»þÅÀ¤Î¾õÂÖ¤ËÌ᤹¤³¤È¤¬¤Ç¤­¤ë¡£

.\"O If
.\"O .I flags
.\"O specifies
.\"O .BR MPOL_F_MEMS_ALLOWED
.\"O (available since Linux 2.6.24), the
.\"O .I mode
.\"O argument is ignored and the set of nodes [memories] that the
.\"O process is allowed to specify in subsequent calls to
.\"O .BR mbind (2)
.\"O or
.\"O .BR set_mempolicy (2)
.\"O [in the absense of any
.\"O .IR "mode flags" ]
.\"O is returned in
.\"O .IR nodemask .
.\"O It is not permitted to combine
.\"O .B MPOL_F_MEMS_ALLOWED
.\"O with either
.\"O .B MPOL_F_ADDR
.\"O or
.\"O .BR MPOL_F_NODE .
.I flags
¤Ë
.B MPOL_F_MEMS_ALLOWED
(Linux 2.6.24 °Ê¹ß¤ÇÍøÍѲÄǽ) ¤ò»ØÄꤹ¤ë¤È¡¢
.I mode
°ú¤­¿ô¤Ï̵»ë¤µ¤ì¡¢
¤½¤Î¥×¥í¥»¥¹¤¬¤½¤Î¸å¤Î
.BR mbind (2)
¤ä
.BR set_mempolicy (2)
¤Ç
.RI [ "¥â¡¼¥É¥Õ¥é¥°"
¤¬»ØÄꤵ¤ì¤Æ¤¤¤Ê¤¤¾ì¹ç¤Ë ] »ØÄê¤Ç¤­¤ë¥Î¡¼¥É (¥á¥â¥ê) ¤Î½¸¹ç¤¬
.I nodemask
¤ËÊÖ¤µ¤ì¤ë¡£
.B MPOL_F_MEMS_ALLOWED
¤ò¡¢
.B MPOL_F_ADDR
¤ä
.B MPOL_F_NODE
¤ÈƱ»þ¤Ë»ØÄꤹ¤ë¤³¤È¤Ï¤Ç¤­¤Ê¤¤¡£

.\"O If
.\"O .I flags
.\"O specifies
.\"O .BR MPOL_F_ADDR ,
.\"O then information is returned about the policy governing the memory
.\"O address given in
.\"O .IR addr .
.\"O This policy may be different from the process's default policy if
.\"O .BR mbind (2)
.\"O or one of the helper functions described in
.\"O .BR numa (3)
.\"O has been used to establish a policy for the memory range containing
.\"O .IR addr .
.I flags
¤Ë
.B MPOL_F_ADDR
¤¬»ØÄꤵ¤ì¤¿¾ì¹ç¡¢
.I addr
¤Ç»ØÄꤵ¤ì¤¿¥á¥â¥ê¥¢¥É¥ì¥¹¤ËŬÍѤµ¤ì¤Æ¤¤¤ë¥Ý¥ê¥·¡¼¤Ë´Ø¤¹¤ë¾ðÊó¤òÊÖ¤¹¡£
.BR mbind (2)
¤ä
.BR numa (3)
¤ÇÀâÌÀ¤µ¤ì¤Æ¤¤¤ë¥Ø¥ë¥Ñ¡¼´Ø¿ô¤ò»È¤Ã¤Æ¡¢
.I addr
¤ò´Þ¤à¥á¥â¥êÎΰè¤ËÂФ¹¤ë¥Ý¥ê¥·¡¼¤¬ÀßÄꤵ¤ì¤Æ¤¤¤¿¾ì¹ç¤Ë¤Ï¡¢
ÊÖ¤µ¤ì¤ë¥Ý¥ê¥·¡¼¤Ï¥×¥í¥»¥¹¤Î¥Ç¥Õ¥©¥ë¥È¥Ý¥ê¥·¡¼¤È°ã¤¦¤³¤È¤¬¤¢¤ë¡£

.\"O If the
.\"O .I mode
.\"O argument is not NULL, then
.\"O .BR get_mempolicy ()
.\"O will store the policy mode and any optional
.\"O .I "mode flags"
.\"O of the requested NUMA policy in the location pointed to by this argument.
.I mode
°ú¤­¿ô¤¬ NULL ¤Ç¤Ê¤¤¾ì¹ç¡¢
.BR get_mempolicy ()
¤ÏÍ׵ᤵ¤ì¤¿ NUMA ¥Ý¥ê¥·¡¼¤Î¥â¡¼¥É¤ÈÄɲäÎ
.I "¥â¡¼¥É¥Õ¥é¥°"
¤ò
.I mode
¤¬»Ø¤¹¾ì½ê¤Ë³ÊǼ¤¹¤ë¡£
.\"O If
.\"O .I nodemask
.\"O is not NULL, then the nodemask associated with the policy will be stored
.\"O in the location pointed to by this argument.
.\"O .I maxnode
.\"O specifies the number of node IDs
.\"O that can be stored into
.\"O .IR nodemask \(emthat
.\"O is, the maximum node ID plus one.
.\"O The value specified by
.\"O .I maxnode
.\"O is always rounded to a multiple of
.\"O .IR "sizeof(unsigned long)" .
.I nodemask
¤¬ NULL °Ê³°¤Î¾ì¹ç¡¢¤½¤Î¥Ý¥ê¥·¡¼¤ËÂбþ¤¹¤ë¥Î¡¼¥É¥Þ¥¹¥¯¤ò
¤³¤Î°ú¤­¿ô¤¬»Ø¤¹¾ì½ê¤Ë³ÊǼ¤¹¤ë¡£
.I maxnode
¤Ë¤Ï
.I nodemask
¤Ë³ÊǼ¤Ç¤­¤ë¥Î¡¼¥É ID ¤Î¿ô¡¢¤Ä¤Þ¤êºÇÂç¥Î¡¼¥É ID ¤Ë 1 ¤ò­¤·¤¿Ãͤò»ØÄꤹ¤ë¡£
.I maxnode
¤Ç»ØÄꤵ¤ì¤¿ÃͤϾï¤Ë
.I sizeof(unsigned long)
¤ÎÇÜ¿ô¤ËÀÚ¤ê¾å¤²¤é¤ì¤ë¡£

.\"O If
.\"O .I flags
.\"O specifies both
.\"O .B MPOL_F_NODE
.\"O and
.\"O .BR MPOL_F_ADDR ,
.\"O .BR get_mempolicy ()
.\"O will return the node ID of the node on which the address
.\"O .I addr
.\"O is allocated into the location pointed to by
.\"O .IR mode .
.\"O If no page has yet been allocated for the specified address,
.\"O .BR get_mempolicy ()
.\"O will allocate a page as if the process had performed a read
.\"O [load] access to that address, and return the ID of the node
.\"O where that page was allocated.
.I flags
¤Ç
.B MPOL_F_NODE
¤È
.B MPOL_F_ADDR
¤ÎξÊý¤¬»ØÄꤵ¤ì¤¿¾ì¹ç¡¢
.BR get_mempolicy ()
¤Ï¥¢¥É¥ì¥¹
.I addr
¤¬³ä¤êÅö¤Æ¤é¤ì¤Æ¤¤¤ë¥Î¡¼¥É¤Î¥Î¡¼¥É ID ¤ò
.I mode
¤¬»Ø¤¹¾ì½ê¤ËÆþ¤ì¤ÆÊÖ¤¹¡£
»ØÄꤵ¤ì¤¿¥¢¥É¥ì¥¹¤Ë¤É¤Î¥Ú¡¼¥¸¤â¤Þ¤À³ä¤êÅö¤Æ¤é¤ì¤Æ¤¤¤Ê¤¤¾ì¹ç¡¢
.BR get_mempolicy ()
¤Ï¡¢¤¢¤¿¤«¤â¤½¤Î¥×¥í¥»¥¹¤¬¤½¤Î¥¢¥É¥ì¥¹¤ËÂФ·¤ÆÆɤ߹þ¤ß¥¢¥¯¥»¥¹¤ò
¼Â¹Ô¤·¤¿¤«¤Î¤è¤¦¤Ë¥Ú¡¼¥¸¤Î³ä¤êÅö¤Æ¤ò¹Ô¤¤¡¢¥Ú¡¼¥¸¤¬³ä¤êÅö¤Æ¤é¤ì¤¿
¥Î¡¼¥É¤Î ID ¤òÊÖ¤¹¡£

.\"O If
.\"O .I flags
.\"O specifies
.\"O .BR MPOL_F_NODE ,
.\"O but not
.\"O .BR MPOL_F_ADDR ,
.\"O and the process's current policy is
.\"O .BR MPOL_INTERLEAVE ,
.\"O then
.\"O .BR get_mempolicy ()
.\"O will return in the location pointed to by a non-NULL
.\"O .I mode
.\"O argument,
.\"O the node ID of the next node that will be used for
.\"O interleaving of internal kernel pages allocated on behalf of the process.
.I flags
¤Ç
.B MPOL_F_NODE
¤Ï»ØÄꤵ¤ì¤¿¤¬¡¢
.B MPOL_F_ADDR
¤Ï»ØÄꤵ¤ì¤Æ¤¤¤Ê¤¤¾ì¹ç¤Ç¡¢¤«¤Ä
¤½¤Î¥×¥í¥»¥¹¤Î¸½ºß¤Î¥Ý¥ê¥·¡¼¤¬
.B MPOL_INTERLEAVE
¤Î¾ì¹ç¡¢
.BR get_mempolicy ()
¤Ï¡¢¤½¤Î¥×¥í¥»¥¹¤ËÂФ·¤Æ³ä¤êÅö¤Æ¤é¤ì¤¿¥«¡¼¥Í¥ë¤ÎÆâÉô¥Ú¡¼¥¸¤Ç
¼¡¤Ë¥¤¥ó¥¿¡¼¥ê¡¼¥ÖÍѤ˻ÈÍѤµ¤ì¤ë¥Î¡¼¥É¤Î¥Î¡¼¥É ID ¤ò¡¢
NULL ¤Ç¤Ê¤¤
.I mode
°ú¤­¿ô¤¬»Ø¤¹¾ì½ê¤ËÆþ¤ì¤ÆÊÖ¤¹¡£
.\" Note:  code returns next interleave node via 'mode' argument -Lee Schermerhorn
.\"O These allocations include pages for memory mapped files in
.\"O process memory ranges mapped using the
.\"O .BR mmap (2)
.\"O call with the
.\"O .B MAP_PRIVATE
.\"O flag for read accesses, and in memory ranges mapped with the
.\"O .B MAP_SHARED
.\"O flag for all accesses.
Æɤ߹þ¤ß¥¢¥¯¥»¥¹ÍѤȤ·¤Æ
.B MAP_PRIVATE
¥Õ¥é¥°ÉÕ¤­¤Ç
.BR mmap (2)
¤·¤¿¥×¥í¥»¥¹¥á¥â¥êÎΰè¤ä¡¢
Ǥ°Õ¤Î¥¢¥¯¥»¥¹ÍѤȤ·¤Æ
.B MAP_SHARED
¥Õ¥é¥°ÉÕ¤­¤Ç
.BR mmap (2)
¤·¤¿¥á¥â¥êÎΰè¤Î¡¢¥á¥â¥ê¥Þ¥Ã¥×¤µ¤ì¤¿¥Õ¥¡¥¤¥ë¤ËÂФ¹¤ë¥Ú¡¼¥¸¤â
¾åµ­¤Î¥×¥í¥»¥¹¤ËÂФ·¤Æ³ä¤êÅö¤Æ¤é¤ì¤¿¥Ú¡¼¥¸¤Ë´Þ¤Þ¤ì¤ë¡£

.\"O Other flag values are reserved.
¾¤Î¥Õ¥é¥°¤ÏͽÌ󤵤ì¤Æ¤¤¤ë¡£

.\"O For an overview of the possible policies see
.\"O .BR set_mempolicy (2).
ÀßÄê²Äǽ¤Ê¥Ý¥ê¥·¡¼¤Î³µÍפˤĤ¤¤Æ¤Ï
.BR set_mempolicy (2)
¤ò»²¾È¡£
.\"O .SH RETURN VALUE
.SH ÊÖ¤êÃÍ
.\"O On success,
.\"O .BR get_mempolicy ()
.\"O returns 0;
.\"O on error, \-1 is returned and
.\"O .I errno
.\"O is set to indicate the error.
À®¸ù¤¹¤ë¤È¡¢
.BR get_mempolicy ()
¤Ï 0 ¤òÊÖ¤¹¡£¥¨¥é¡¼¤Î¾ì¹ç¡¢\-1 ¤òÊÖ¤·¡¢
.I errno
¤Ë¥¨¥é¡¼¤ò¼¨¤¹ÃͤòÀßÄꤹ¤ë¡£
.\"O .SH ERRORS
.SH ¥¨¥é¡¼
.TP
.B EFAULT
.\"O Part of all of the memory range specified by
.\"O .I nodemask
.\"O and
.\"O .I maxnode
.\"O points outside your accessible address space.
.\"motoki: Part of all of the memory ¤Ï Part or all .. ¤Î´Ö°ã¤¤¡©
.I nodemask
¤È
.I maxnode
¤Ç»ØÄꤵ¤ì¤¿¥á¥â¥êÎΰè¤Î°ìÉô¤Þ¤¿¤ÏÁ´Éô¤¬¡¢
¸Æ¤Ó½Ð¤·¸µ¤¬¥¢¥¯¥»¥¹²Äǽ¤Ê¥¢¥É¥ì¥¹¶õ´Ö³°¤ò»Ø¤·¤Æ¤¤¤ë¡£
.TP
.B EINVAL
.\"O The value specified by
.\"O .I maxnode
.\"O is less than the number of node IDs supported by the system.
.I maxnode
¤Ç»ØÄꤵ¤ì¤¿Ãͤ¬¥·¥¹¥Æ¥à¤¬¥µ¥Ý¡¼¥È¤¹¤ë¥Î¡¼¥É ID ¤Î¿ô¤è¤ê¤â¾¯¤Ê¤¤¡£
.\"O Or
.\"O .I flags
.\"O specified values other than
.\"O .B MPOL_F_NODE
.\"O or
.\"O .BR MPOL_F_ADDR ;
¤Þ¤¿¤Ï¡¢
.I flags
¤Ë
.B MPOL_F_NODE
¤Ç¤â
.B MPOL_F_ADDR
¤Ç¤â¤Ê¤¤Ãͤ¬»ØÄꤵ¤ì¤¿¡£
.\"O or
.\"O .I flags
.\"O specified
.\"O .B MPOL_F_ADDR
.\"O and
.\"O .I addr
.\"O is NULL,
¤Þ¤¿¤Ï¡¢
.I flags
¤Ë
.B MPOL_F_ADDR
¤¬»ØÄꤵ¤ì¤Æ¤ª¤ê¡¢
.I addr
¤¬ NULL ¤Ç¤¢¤ë¡£
.\"O or
.\"O .I flags
.\"O did not specify
.\"O .B MPOL_F_ADDR
.\"O and
.\"O .I addr
.\"O is not NULL.
¤Þ¤¿¤Ï¡¢
.I flags
¤Ë
.B MPOL_F_ADDR
¤¬¤µ¤ì¤Æ¤ª¤é¤º¡¢
.I addr
¤¬ NULL ¤Ç¤Ê¤¤¡£
.\"O Or,
.\"O .I flags
.\"O specified
.\"O .B MPOL_F_NODE
.\"O but not
.\"O .B MPOL_F_ADDR
.\"O and the current process policy is not
.\"O .BR MPOL_INTERLEAVE .
¤Þ¤¿¤Ï¡¢
.I flags
¤Ë
.B MPOL_F_NODE
¤¬»ØÄꤵ¤ì¤Æ¤ª¤ê¡¢
.B MPOL_F_ADDR
¤¬»ØÄꤵ¤ì¤Æ¤ª¤é¤º¡¢
¥×¥í¥»¥¹¤Î¸½ºß¤Î¥Ý¥ê¥·¡¼¤¬
.B MPOL_INTERLEAVE
¤Ç¤Ê¤¤¡£
.\"O Or,
.\"O .I flags
.\"O specified
.\"O .B MPOL_F_MEMS_ALLOWED
.\"O with either
.\"O .B MPOL_F_ADDR
.\"O or
.\"O .BR MPOL_F_NODE .
¤Þ¤¿¤Ï¡¢
.I flags
¤Ë
.B MPOL_F_MEMS_ALLOWED
¤¬»ØÄꤵ¤ì¤Æ¤ª¤ê¡¢¤µ¤é¤Ë
.B MPOL_F_ADDR
¤«
.B MPOL_F_NODE
¤Î¤¤¤º¤ì¤«¤¬»ØÄꤵ¤ì¤Æ¤¤¤ë¡£
.\"O (And there are other
.\"O .B EINVAL
.\"O cases.)
(¾¤Ë¤â
.B EINVAL
¤È¤Ê¤ë¾ì¹ç¤¬¤¢¤ë¡£)
.\"O .SH VERSIONS
.SH ¥Ð¡¼¥¸¥ç¥ó
.\"O The
.\"O .BR get_mempolicy ()
.\"O system call was added to the Linux kernel in version 2.6.7.
.BR get_mempolicy ()
¥·¥¹¥Æ¥à¥³¡¼¥ë¤Ï¥Ð¡¼¥¸¥ç¥ó 2.6.7 ¤Ç Linux ¥«¡¼¥Í¥ë¤ËÄɲ䵤줿¡£
.\"O .SH CONFORMING TO
.SH ½àµò
.\"O This system call is Linux-specific.
¤³¤Î¥·¥¹¥Æ¥à¥³¡¼¥ë¤Ï Linux ¸ÇÍ­¤Ç¤¢¤ë¡£
.\"O .SH NOTES
.SH Ãí°Õ
.\"O For information on library support, see
.\"O .BR numa (7).
¥é¥¤¥Ö¥é¥ê¤Ë¤è¤ë¥µ¥Ý¡¼¥È¤Ë¤Ä¤¤¤Æ¤Ï
.BR numa (7)
¤ò»²¾È¡£
.\"O .SH SEE ALSO
.SH ´ØÏ¢¹àÌÜ
.BR getcpu (2),
.BR mbind (2),
.BR mmap (2),
.BR set_mempolicy (2),
.BR numa (3),
.BR numa (7),
.BR numactl (8)