Mercurial > hg > octave-lyh > gnulib-hg
changeset 5673:dbfd56933568
New module 'pagealign_alloc'.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Thu, 03 Mar 2005 14:07:04 +0000 |
parents | 95abd6955c14 |
children | 8799b424105a |
files | ChangeLog lib/ChangeLog lib/pagealign_alloc.c lib/pagealign_alloc.h m4/ChangeLog m4/mmap-anon.m4 m4/pagealign_alloc.m4 modules/pagealign_alloc |
diffstat | 8 files changed, 324 insertions(+), 0 deletions(-) [+] |
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--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2005-03-03 Derek R. Price <derek@ximbiot.com> + Bruno Haible <bruno@clisp.org> + + * modules/pagealign_alloc: New file. + * MODULES.html.sh (Memory management functions): Add pagealign_alloc. + 2005-03-01 Paul Eggert <eggert@cs.ucla.edu> * modules/gettime (Makefile.am): Remove lib_SOURCES line.
--- a/lib/ChangeLog +++ b/lib/ChangeLog @@ -1,3 +1,9 @@ +2005-03-03 Derek R. Price <derek@ximbiot.com> + Bruno Haible <bruno@clisp.org> + + * pagealign_alloc.h: New file. + * pagealign_alloc.c: New file. + 2005-01-28 Bruno Haible <bruno@clisp.org> * stpncpy.h (stpncpy): Define as a macro without arguments, so that
new file mode 100644 --- /dev/null +++ b/lib/pagealign_alloc.c @@ -0,0 +1,164 @@ +/* Memory allocation aligned to system page boundaries. + + Copyright (C) 2005 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published + by the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public + License along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + USA. */ + +/* Written by Derek R. Price <derek@ximbiot.com>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include "pagealign_alloc.h" + +#include <errno.h> +#include <stdlib.h> + +#if HAVE_FCNTL_H +# include <fcntl.h> +#endif + +#if HAVE_UNISTD_H +# include <unistd.h> +#endif + +#if HAVE_MMAP +# include <sys/mman.h> +#endif + +#include "error.h" +#include "exit.h" +#include "getpagesize.h" +#include "xalloc.h" + + +#if HAVE_MMAP || ! HAVE_POSIX_MEMALIGN + +# if HAVE_MMAP +/* For each memory region, we store its size. */ +typedef size_t info_t; +# else +/* For each memory region, we store the original pointer returned by + malloc(). */ +typedef void * info_t; +# endif + +/* A simple linked list of allocated memory regions. It is probably not the + most efficient way to store these, but anyway... */ +typedef struct memnode_s memnode_t; +struct memnode_s +{ + void *aligned_ptr; + info_t info; + memnode_t *next; +}; + +/* The list of currently allocated memory regions. */ +static memnode_t *memnode_table = NULL; + + +static void +new_memnode (void *aligned_ptr, info_t info) +{ + memnode_t *new_node = (memnode_t *) xmalloc (sizeof (memnode_t)); + new_node->aligned_ptr = aligned_ptr; + new_node->info = info; + new_node->next = memnode_table; + memnode_table = new_node; +} + + +/* Dispose of the memnode containing a map for the ALIGNED_PTR in question + and return the content of the node's INFO field. */ +static info_t +get_memnode (void *aligned_ptr) +{ + info_t ret; + memnode_t *c; + memnode_t **p_next = &memnode_table; + + for (c = *p_next; c != NULL; p_next = &c->next, c = c->next) + if (c->aligned_ptr == aligned_ptr) + break; + + if (!c) + /* An attempt to free untracked memory. A wrong pointer was passed + to pagealign_free(). */ + abort (); + + /* Remove this entry from the list, save the return value, and free it. */ + *p_next = c->next; + ret = c->info; + free (c); + + return ret; +} + +#endif /* HAVE_MMAP || !HAVE_POSIX_MEMALIGN */ + + +void * +pagealign_alloc (size_t size) +{ + void *ret; +#if HAVE_MMAP + int flags; + static int fd = -1; /* Only open /dev/zero once in order to avoid limiting + the amount of memory we may allocate based on the + number of open file descriptors. */ +# ifdef HAVE_MAP_ANONYMOUS + flags = MAP_ANONYMOUS | MAP_PRIVATE; + fd = -1; +# else /* !HAVE_MAP_ANONYMOUS */ + flags = MAP_FILE | MAP_PRIVATE; + if (fd == -1) + { + fd = open ("/dev/zero", O_RDONLY, 0666); + if (fd < 0) + error (EXIT_FAILURE, errno, "Failed to open /dev/zero for read"); + } +# endif /* HAVE_MAP_ANONYMOUS */ + ret = mmap (NULL, size, PROT_READ | PROT_WRITE, flags, fd, 0); + if (!ret) + error (EXIT_FAILURE, errno, "mmap to /dev/zero failed"); + new_memnode (ret, size); +#elif HAVE_POSIX_MEMALIGN + int status = posix_memalign (&ret, getpagesize (), size); + if (status) + error (EXIT_FAILURE, status, "posix_memalign failed"); +#else /* !HAVE_MMAP && !HAVE_POSIX_MEMALIGN */ + size_t pagesize = getpagesize (); + void *unaligned_ptr = xmalloc (size + pagesize - 1); + ret = (char *) unaligned_ptr + + ((- (unsigned long) unaligned_ptr) & (pagesize - 1)); + new_memnode (ret, unaligned_ptr); +#endif /* HAVE_MMAP && HAVE_POSIX_MEMALIGN */ + return ret; +} + + +void +pagealign_free (void *aligned_ptr) +{ +#if HAVE_MMAP + munmap (aligned_ptr, get_memnode (aligned_ptr)); +#elif HAVE_POSIX_MEMALIGN + free (aligned_ptr); +#else + free (get_memnode (aligned_ptr)); +#endif +}
new file mode 100644 --- /dev/null +++ b/lib/pagealign_alloc.h @@ -0,0 +1,37 @@ +/* Memory allocation aligned to system page boundaries. + + Copyright (C) 2005 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published + by the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public + License along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + USA. */ + +#ifndef _PAGEALIGN_ALLOC_H +# define _PAGEALIGN_ALLOC_H + +# include <stddef.h> + +/* Allocate a block of memory of SIZE bytes, aligned on a system page + boundary. + If SIZE is not a multiple of the system page size, it will be rounded up + to the next multiple. + Return a pointer to the start of the memory block, or NULL if the allocation + failed. */ +extern void *pagealign_alloc (size_t size); + +/* Free a memory block. + PTR must be a pointer returned by pagealign_alloc. */ +extern void pagealign_free (void *ptr); + +#endif /* _PAGEALIGN_ALLOC_H */
--- a/m4/ChangeLog +++ b/m4/ChangeLog @@ -1,3 +1,8 @@ +2005-03-03 Derek R. Price <derek@ximbiot.com> + + * mmap-anon.m4: New file. + * pagealign_alloc.m4: New file. + 2005-01-28 Bruno Haible <bruno@clisp.org> * stpncpy.m4 (gl_FUNC_STPNCPY): Undo the replacement here. Because of
new file mode 100644 --- /dev/null +++ b/m4/mmap-anon.m4 @@ -0,0 +1,54 @@ +# mmap-anon.m4 serial 1 +dnl Copyright (C) 2005 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_FUNC_MMAP], +[ + dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57. + AC_REQUIRE([AC_PROG_CPP]) + AC_REQUIRE([AC_PROG_EGREP]) + + dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS. + AC_REQUIRE([AC_GNU_SOURCE]) + + # Check for mmap() + AC_FUNC_MMAP + + # Try to allow MAP_ANONYMOUS. + gl_have_mmap_anonymous=no + if test $ac_cv_func_mmap_fixed_mapped = yes; then + AC_MSG_CHECKING([for MAP_ANONYMOUS]) + AC_EGREP_CPP([I cant identify this map.], [ +#include <sys/mman.h> +#ifdef MAP_ANONYMOUS + I cant identify this map. +#endif +], + [gl_have_mmap_anonymous=yes]) + if test $gl_have_mmap_anonymous = no; then + AC_EGREP_HEADER([MAP_ANON], [ +#include <sys/mman.h> +#ifdef MAP_ANON + I cant identify this map. +#endif +], + [AC_DEFINE(MAP_ANONYMOUS, MAP_ANON, + [Define to a substitute value for mmap()'s MAP_ANONYMOUS flag.]) + gl_have_mmap_anonymous=yes]) + fi + AC_MSG_RESULT($gl_have_mmap_anonymous) + if test $gl_have_mmap_anonymous = yes; then + AC_DEFINE(HAVE_MAP_ANONYMOUS, 1, + [Define to 1 if mmap()'s MAP_ANONYMOUS flag is available after including + config.h and <sys/mman.h>.]) + fi + + AH_VERBATIM([MAP_FILE], +[/* Define MAP_FILE when it isn't otherwise. */ +#ifndef MAP_FILE +# define MAP_FILE 0 +#endif]) + fi +])
new file mode 100644 --- /dev/null +++ b/m4/pagealign_alloc.m4 @@ -0,0 +1,24 @@ +# pagealign_alloc.m4 serial 1 +dnl Copyright (C) 2005 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_PAGEALIGN_ALLOC], +[ + dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS. + AC_REQUIRE([AC_GNU_SOURCE]) + + AC_LIBSOURCE([pagealign_alloc.h]) + AC_LIBOBJ([pagealign_alloc]) + gl_PREREQ_PAGEALIGN_ALLOC +]) + +# Prerequisites of lib/pagealign_alloc.c. +AC_DEFUN([gl_PREREQ_PAGEALIGN_ALLOC], +[ + AC_REQUIRE([gl_FUNC_MMAP]) + AC_REQUIRE([gl_GETPAGESIZE]) + AC_CHECK_FUNCS_ONCE([posix_memalign]) + AC_CHECK_HEADERS_ONCE([fcntl.h unistd.h]) +])
new file mode 100644 --- /dev/null +++ b/modules/pagealign_alloc @@ -0,0 +1,28 @@ +Description: +Memory allocation aligned on page boundaries. + +Files: +lib/pagealign_alloc.h +lib/pagealign_alloc.c +m4/mmap-anon.m4 +m4/pagealign_alloc.m4 + +Depends-on: +error +exit +getpagesize +xalloc + +configure.ac: +gl_PAGEALIGN_ALLOC + +Makefile.am: + +Include: +#include "pagealign_alloc.h" + +License: +GPL + +Maintainer: +bug-gnulib@gnu.org