X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/c3d49b133b582d863f53002530ed7c65ad6dbcae..41c54c2772412935a5c8fc9f2d09e623c0383ae7:/src/xbt/mmalloc/mmorecore.c diff --git a/src/xbt/mmalloc/mmorecore.c b/src/xbt/mmalloc/mmorecore.c index 76ff04b876..4a9cbb55e3 100644 --- a/src/xbt/mmalloc/mmorecore.c +++ b/src/xbt/mmalloc/mmorecore.c @@ -1,17 +1,14 @@ -/* Support for an sbrk-like function that uses mmap. - Copyright 1992, 2000 Free Software Foundation, Inc. +/* Support for an sbrk-like function that uses mmap. */ - Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com */ - -/* Copyright (c) 2010. The SimGrid Team. +/* Copyright (c) 2010-2014. The SimGrid Team. * All rights reserved. */ /* This program is free software; you can redistribute it and/or modify it * under the terms of the license (GNU LGPL) which comes with this package. */ -#ifndef MAP_ANONYMOUS -#define MAP_ANONYMOUS MAP_ANON -#endif +/* Copyright 1992, 2000 Free Software Foundation, Inc. + + Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com */ #ifdef HAVE_UNISTD_H #include /* Prototypes for lseek */ @@ -19,53 +16,54 @@ #include #include #include +#include #include "mmprivate.h" -#include "xbt/ex.h" - -/* Cache the pagesize for the current host machine. Note that if the host - does not readily provide a getpagesize() function, we need to emulate it - elsewhere, not clutter up this file with lots of kluges to try to figure - it out. */ -static size_t pagesize; +#ifndef MAP_ANONYMOUS +#define MAP_ANONYMOUS MAP_ANON +#endif -#define PAGE_ALIGN(addr) (void*) (((long)(addr) + pagesize - 1) & \ - ~(pagesize - 1)) +#define PAGE_ALIGN(addr) (void*) (((long)(addr) + xbt_pagesize - 1) & \ + ~((long)xbt_pagesize - 1)) /* Return MAP_PRIVATE if MDP represents /dev/zero. Otherwise, return MAP_SHARED. */ #define MAP_PRIVATE_OR_SHARED(MDP) (( MDP -> flags & MMALLOC_ANONYMOUS) \ - ? MAP_PRIVATE \ + ? MAP_PRIVATE \ : MAP_SHARED) /* Return MAP_ANONYMOUS if MDP uses anonymous mapping. Otherwise, return 0 */ #define MAP_IS_ANONYMOUS(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \ - ? MAP_ANONYMOUS \ - : 0) + ? MAP_ANONYMOUS \ + : 0) /* Return -1 if MDP uses anonymous mapping. Otherwise, return MDP->FD */ #define MAP_ANON_OR_FD(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \ - ? -1 \ - : (MDP) -> fd) - -/* Get core for the memory region specified by MDP, using SIZE as the - amount to either add to or subtract from the existing region. Works - like sbrk(), but using mmap(). */ - -void *mmorecore(struct mdesc *mdp, int size) + ? -1 \ + : (MDP) -> fd) + +/** @brief Add memoty to this heap + * + * Get core for the memory region specified by MDP, using SIZE as the + * amount to either add to or subtract from the existing region. Works + * like sbrk(), but using mmap(). + * + * It never returns NULL. Instead, it dies verbosely on errors. + * + * @param mdp The heap + * @param size Bytes to allocate for this heap (or <0 to free memory from this heap) + */ +void *mmorecore(struct mdesc *mdp, ssize_t size) { ssize_t test = 0; - void *result = NULL; + void *result; // please keep it uninitialized to track issues off_t foffset; /* File offset at which new mapping will start */ size_t mapbytes; /* Number of bytes to map */ void *moveto; /* Address where we wish to move "break value" to */ void *mapto; /* Address we actually mapped to */ char buf = 0; /* Single byte to write to extend mapped file */ - if (pagesize == 0) - pagesize = getpagesize(); - if (size == 0) { /* Just return the current "break" value. */ result = mdp->breakval; @@ -73,8 +71,8 @@ void *mmorecore(struct mdesc *mdp, int size) } else if (size < 0) { /* We are deallocating memory. If the amount requested would cause us to try to deallocate back past the base of the mmap'd region - then do nothing, and return NULL. Otherwise, deallocate the - memory and return the old break value. */ + then die verbosely. Otherwise, deallocate the memory and return + the old break value. */ if (((char *) mdp->breakval) + size >= (char *) mdp->base) { result = (void *) mdp->breakval; mdp->breakval = (char *) mdp->breakval + size; @@ -82,13 +80,16 @@ void *mmorecore(struct mdesc *mdp, int size) munmap(moveto, (size_t) (((char *) mdp->top) - ((char *) moveto)) - 1); mdp->top = moveto; + } else { + fprintf(stderr,"Internal error: mmap was asked to deallocate more memory than it previously allocated. Bailling out now!\n"); + abort(); } } else { /* We are allocating memory. Make sure we have an open file descriptor if not working with anonymous memory. */ if (!(mdp->flags & MMALLOC_ANONYMOUS) && mdp->fd < 0) { - THROWF(system_error,0,"mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags",mdp->fd); - result = NULL; + fprintf(stderr,"Internal error: mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags.\n",mdp->fd); + abort(); } else if ((char *) mdp->breakval + size > (char *) mdp->top) { /* The request would move us past the end of the currently mapped memory, so map in enough more memory to satisfy @@ -103,28 +104,40 @@ void *mmorecore(struct mdesc *mdp, int size) /* FIXME: Test results of lseek() */ lseek(mdp->fd, foffset + mapbytes - 1, SEEK_SET); test = write(mdp->fd, &buf, 1); - if (test == -1) - THROWF(system_error, 0, "write to mmap'ed fd failed! error: %s", strerror(errno)); + if (test == -1) { + fprintf(stderr,"Internal error: write to mmap'ed fd failed! error: %s", strerror(errno)); + abort(); + } } /* Let's call mmap. Note that it is possible that mdp->top - is 0. In this case mmap will choose the address for us */ + is 0. In this case mmap will choose the address for us. + This call might very well overwrite an already existing memory mapping + (leading to weird bugs). + */ mapto = mmap(mdp->top, mapbytes, PROT_READ | PROT_WRITE, MAP_PRIVATE_OR_SHARED(mdp) | MAP_IS_ANONYMOUS(mdp) | MAP_FIXED, MAP_ANON_OR_FD(mdp), foffset); - if (mapto != (void *) -1/* That's MAP_FAILED */) { + if (mapto == MAP_FAILED) { + char buff[1024]; + fprintf(stderr,"Internal error: mmap returned MAP_FAILED! error: %s\n",strerror(errno)); + sprintf(buff,"cat /proc/%d/maps",getpid()); + int status = system(buff); + if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0)) + fprintf(stderr, "Something went wrong when trying to %s\n", buff); + sleep(1); + abort(); + } - if (mdp->top == 0) - mdp->base = mdp->breakval = mapto; + if (mdp->top == 0) + mdp->base = mdp->breakval = mapto; - mdp->top = PAGE_ALIGN((char *) mdp->breakval + size); - result = (void *) mdp->breakval; - mdp->breakval = (char *) mdp->breakval + size; - } else { - THROWF(system_error,0,"mmap returned MAP_FAILED! error: %s",strerror(errno)); - } + mdp->top = PAGE_ALIGN((char *) mdp->breakval + size); + result = (void *) mdp->breakval; + mdp->breakval = (char *) mdp->breakval + size; } else { + /* Memory is already mapped, we only need to increase the breakval: */ result = (void *) mdp->breakval; mdp->breakval = (char *) mdp->breakval + size; } @@ -132,15 +145,12 @@ void *mmorecore(struct mdesc *mdp, int size) return (result); } -void *__mmalloc_remap_core(struct mdesc *mdp) +void *__mmalloc_remap_core(xbt_mheap_t mdp) { - void *base; - /* FIXME: Quick hack, needs error checking and other attention. */ - base = mmap(mdp->base, (char *) mdp->top - (char *) mdp->base, + return mmap(mdp->base, (char*) mdp->top - (char*) mdp->base, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE_OR_SHARED(mdp) | MAP_FIXED, mdp->fd, 0); - return ((void *) base); }