X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/5185459eab2702b1ad78f481149ef411809336f5..5c866e44376ab5dcb4fcfc2725cdd6d47168236a:/src/xbt/mmalloc/mm_module.c diff --git a/src/xbt/mmalloc/mm_module.c b/src/xbt/mmalloc/mm_module.c index cd4d7b70f7..5c95f1a427 100644 --- a/src/xbt/mmalloc/mm_module.c +++ b/src/xbt/mmalloc/mm_module.c @@ -32,35 +32,14 @@ #include /* After sys/types.h, at least for dpx/2. */ #include #include -#if HAVE_UNISTD_H -#include /* Prototypes for lseek */ -#endif #include "mmprivate.h" #include "xbt/ex.h" #include "xbt/xbt_modinter.h" /* declarations of mmalloc_preinit and friends that live here */ -#ifndef SEEK_SET -#define SEEK_SET 0 -#endif - /* Initialize access to a mmalloc managed region. - If FD is a valid file descriptor for an open file then data for the - mmalloc managed region is mapped to that file, otherwise an anonymous - map is used if supported by the underlying OS. In case of running in - an OS without support of anonymous mappings then "/dev/zero" is used - and in both cases the data will not exist in any filesystem object. - - If the open file corresponding to FD is from a previous use of - mmalloc and passes some basic sanity checks to ensure that it is - compatible with the current mmalloc package, then its data is - mapped in and is immediately accessible at the same addresses in - the current process as the process that created the file (ignoring - the BASEADDR parameter). - - For non valid FDs or empty files ones the mapping is established - starting at the specified address BASEADDR in the process address - space. + The mapping is established starting at the specified address BASEADDR + in the process address space. The provided BASEADDR should be chosen carefully in order to avoid bumping into existing mapped regions or future mapped regions. @@ -72,91 +51,8 @@ On failure returns NULL. */ -xbt_mheap_t xbt_mheap_new(int fd, void *baseaddr) -{ - return xbt_mheap_new_options(fd, baseaddr, 0); -} - -xbt_mheap_t xbt_mheap_new_options(int fd, void *baseaddr, int options) +xbt_mheap_t xbt_mheap_new(void* baseaddr, int options) { - struct mdesc mtemp; - xbt_mheap_t mdp; - void *mbase; - struct stat sbuf; - - /* First check to see if FD is a valid file descriptor, and if so, see - if the file has any current contents (size > 0). If it does, then - attempt to reuse the file. If we can't reuse the file, either - because it isn't a valid mmalloc produced file, was produced by an - obsolete version, or any other reason, then we fail to attach to - this file. */ - - if (fd >= 0) { - if (fstat(fd, &sbuf) < 0) - return NULL; - - else if (sbuf.st_size > 0) { - /* We were given a valid file descriptor on an open file, so try to remap - it into the current process at the same address to which it was previously - mapped. It naturally have to pass some sanity checks for that. - - Note that we have to update the file descriptor number in the malloc- - descriptor read from the file to match the current valid one, before - trying to map the file in, and again after a successful mapping and - after we've switched over to using the mapped in malloc descriptor - rather than the temporary one on the stack. - - Once we've switched over to using the mapped in malloc descriptor, we - have to update the pointer to the morecore function, since it almost - certainly will be at a different address if the process reusing the - mapped region is from a different executable. - - Also note that if the heap being remapped previously used the mmcheckf() - routines, we need to update the hooks since their target functions - will have certainly moved if the executable has changed in any way. - We do this by calling mmcheckf() internally. - - Returns a pointer to the malloc descriptor if successful, or NULL if - unsuccessful for some reason. */ - - struct mdesc newmd; - struct mdesc* mdptr = NULL; - struct mdesc* mdptemp = NULL; - - if (lseek(fd, 0L, SEEK_SET) != 0) - return NULL; - if (read(fd, (char *) &newmd, sizeof(newmd)) != sizeof(newmd)) - return NULL; - if (newmd.headersize != sizeof(newmd)) - return NULL; - if (strcmp(newmd.magic, MMALLOC_MAGIC) != 0) - return NULL; - if (newmd.version > MMALLOC_VERSION) - return NULL; - - newmd.fd = fd; - if (__mmalloc_remap_core(&newmd) == newmd.base) { - mdptr = (struct mdesc *) newmd.base; - mdptr->fd = fd; - if(!mdptr->refcount){ - pthread_mutex_init(&mdptr->mutex, NULL); - mdptr->refcount++; - } - } - - /* Add the new heap to the linked list of heaps attached by mmalloc */ - mdptemp = __mmalloc_default_mdp; - while(mdptemp->next_mdesc) - mdptemp = mdptemp->next_mdesc; - - LOCK(mdptemp); - mdptemp->next_mdesc = mdptr; - UNLOCK(mdptemp); - - return mdptr; - } - } - /* NULL is not a valid baseaddr as we cannot map anything there. C'mon, user. Think! */ if (baseaddr == NULL) return NULL; @@ -165,23 +61,16 @@ xbt_mheap_t xbt_mheap_new_options(int fd, void *baseaddr, int options) * call _mmalloc_mmap_morecore() to allocate the first page of the region and copy it there. Ensure that it is * zero'd and then initialize the fields that we know values for. */ - mdp = &mtemp; + struct mdesc mtemp; + xbt_mheap_t mdp = &mtemp; memset((char *) mdp, 0, sizeof(mtemp)); strncpy(mdp->magic, MMALLOC_MAGIC, MMALLOC_MAGIC_SIZE); mdp->headersize = sizeof(mtemp); mdp->version = MMALLOC_VERSION; - mdp->fd = fd; mdp->base = mdp->breakval = mdp->top = baseaddr; mdp->next_mdesc = NULL; - mdp->refcount = 1; mdp->options = options; - /* If we have not been passed a valid open file descriptor for the file - to map to, then we go for an anonymous map */ - - if (mdp->fd < 0){ - mdp->flags |= MMALLOC_ANONYMOUS; - } pthread_mutex_init(&mdp->mutex, NULL); /* If we have not been passed a valid open file descriptor for the file to map to, then open /dev/zero and use that to map to. */ @@ -190,12 +79,12 @@ xbt_mheap_t xbt_mheap_new_options(int fd, void *baseaddr, int options) * this new copy. If the mapping fails, then close the file descriptor if it was opened by us, and arrange to return * a NULL. */ - if ((mbase = mmorecore(mdp, sizeof(mtemp))) != NULL) { - memcpy(mbase, mdp, sizeof(mtemp)); - } else { + void* mbase = mmorecore(mdp, sizeof(mtemp)); + if (mbase == NULL) { fprintf(stderr, "morecore failed to get some more memory!\n"); abort(); } + memcpy(mbase, mdp, sizeof(mtemp)); /* Add the new heap to the linked list of heaps attached by mmalloc */ if(__mmalloc_default_mdp){ @@ -222,9 +111,7 @@ void xbt_mheap_destroy_no_free(xbt_mheap_t md) { struct mdesc *mdp = md; - if(--mdp->refcount == 0){ - pthread_mutex_destroy(&mdp->mutex); - } + pthread_mutex_destroy(&mdp->mutex); } /** Terminate access to a mmalloc managed region by unmapping all memory pages associated with the region, and closing @@ -258,9 +145,6 @@ void *xbt_mheap_destroy(xbt_mheap_t mdp) /* Deallocating failed. Update the original malloc descriptor with any changes */ *mdp = mtemp; } else { - if (mtemp.flags & MMALLOC_DEVZERO) { - close(mtemp.fd); - } mdp = NULL; } } @@ -278,9 +162,6 @@ static void mmalloc_fork_prepare(void) if ((mdp =__mmalloc_default_mdp)){ while(mdp){ LOCK(mdp); - if(mdp->fd >= 0){ - mdp->refcount++; - } mdp = mdp->next_mdesc; } } @@ -291,8 +172,7 @@ static void mmalloc_fork_parent(void) xbt_mheap_t mdp = NULL; if ((mdp =__mmalloc_default_mdp)){ while(mdp){ - if(mdp->fd < 0) - UNLOCK(mdp); + UNLOCK(mdp); mdp = mdp->next_mdesc; } } @@ -317,7 +197,7 @@ xbt_mheap_t mmalloc_preinit(void) xbt_pagesize = getpagesize(); unsigned long mask = ~((unsigned long)xbt_pagesize - 1); void *addr = (void*)(((unsigned long)sbrk(0) + HEAP_OFFSET) & mask); - __mmalloc_default_mdp = xbt_mheap_new_options(-1, addr, XBT_MHEAP_OPTION_MEMSET); + __mmalloc_default_mdp = xbt_mheap_new(addr, XBT_MHEAP_OPTION_MEMSET); // atfork mandated at least on FreeBSD, or simgrid-mc will fail to fork the verified app int res = pthread_atfork(mmalloc_fork_prepare, mmalloc_fork_parent, mmalloc_fork_child);