/* Free a block allocated by `mmalloc', `mrealloc' or `mcalloc'. */
XBT_PUBLIC void mfree(xbt_mheap_t md, void* ptr);
-XBT_PUBLIC xbt_mheap_t xbt_mheap_new(int fd, void* baseaddr);
-
#define XBT_MHEAP_OPTION_MEMSET 1
-XBT_PUBLIC xbt_mheap_t xbt_mheap_new_options(int fd, void* baseaddr, int options);
+XBT_PUBLIC xbt_mheap_t xbt_mheap_new(void* baseaddr, int options);
XBT_PUBLIC void xbt_mheap_destroy_no_free(xbt_mheap_t md);
#include <fcntl.h> /* After sys/types.h, at least for dpx/2. */
#include <sys/stat.h>
#include <string.h>
-#if HAVE_UNISTD_H
-#include <unistd.h> /* 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.
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;
* 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. */
* 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){
{
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
/* Deallocating failed. Update the original malloc descriptor with any changes */
*mdp = mtemp;
} else {
- if (mtemp.flags & MMALLOC_DEVZERO) {
- close(mtemp.fd);
- }
mdp = NULL;
}
}
if ((mdp =__mmalloc_default_mdp)){
while(mdp){
LOCK(mdp);
- if(mdp->fd >= 0){
- mdp->refcount++;
- }
mdp = mdp->next_mdesc;
}
}
xbt_mheap_t mdp = NULL;
if ((mdp =__mmalloc_default_mdp)){
while(mdp){
- if(mdp->fd < 0)
- UNLOCK(mdp);
+ UNLOCK(mdp);
mdp = mdp->next_mdesc;
}
}
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);
Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com */
#include "src/internal_config.h"
-#if HAVE_UNISTD_H
-#include <unistd.h> /* Prototypes for lseek */
-#endif
#include <stdio.h>
#include <fcntl.h>
#include <sys/mman.h>
#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_SHARED)
-
-/* Return MAP_ANONYMOUS if MDP uses anonymous mapping. Otherwise, return 0 */
-#define MAP_IS_ANONYMOUS(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
- ? 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)
-
-/* Return 0if MDP uses anonymous mapping. Otherwise, return off */
-#define MAP_ANON_OR_OFFSET(MDP, off) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
- ? 0 \
- : off)
-
/** @brief Add memory to this heap
*
* Get core for the memory region specified by MDP, using SIZE as the
void *mmorecore(struct mdesc *mdp, ssize_t size)
{
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 (size == 0) {
/* Just return the current "break" value. */
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) {
- fprintf(stderr,"Internal error: mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags.\n",mdp->fd);
+ } 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
+ the request. This means we also have to grow the mapped-to file by an appropriate amount, since mmap cannot
+ be used to extend a file. */
+ moveto = PAGE_ALIGN((char*)mdp->breakval + size);
+ mapbytes = (char*)moveto - (char*)mdp->top;
+
+ /* Let's call mmap. Note that it is possible that mdp->top 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 | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+
+ if (mapto == MAP_FAILED) {
+ char buff[1024];
+ fprintf(stderr, "Internal error: mmap returned MAP_FAILED! error: %s\n", strerror(errno));
+ snprintf(buff, 1024, "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();
- } 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
- the request. This means we also have to grow the mapped-to file by an appropriate amount, since mmap cannot
- be used to extend a file. */
- moveto = PAGE_ALIGN((char*)mdp->breakval + size);
- mapbytes = (char*)moveto - (char*)mdp->top;
- foffset = (char*)mdp->top - (char*)mdp->base;
-
- if (mdp->fd > 0) {
- if (lseek(mdp->fd, foffset + mapbytes - 1, SEEK_SET) == -1) {
- fprintf(stderr, "Internal error: lseek into mmap'ed fd failed! error: %s", strerror(errno));
- abort();
- }
- if (write(mdp->fd, &buf, 1) == -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.
- 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), MAP_ANON_OR_OFFSET(mdp, foffset));
-
- if (mapto == MAP_FAILED) {
- char buff[1024];
- fprintf(stderr,"Internal error: mmap returned MAP_FAILED! error: %s\n",strerror(errno));
- snprintf(buff,1024,"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 = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- } else {
- /* Memory is already mapped, we only need to increase the breakval: */
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- }
+ mdp->top = PAGE_ALIGN((char*)mdp->breakval + size);
+ result = mdp->breakval;
+ mdp->breakval = (char*)mdp->breakval + size;
+ } else {
+ /* Memory is already mapped, we only need to increase the breakval: */
+ result = mdp->breakval;
+ mdp->breakval = (char*)mdp->breakval + size;
}
return result;
}
-
-void* __mmalloc_remap_core(const s_xbt_mheap_t* mdp)
-{
- /* FIXME: Quick hack, needs error checking and other attention. */
-
- 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);
-}
-
/** @brief Mutex locking the access to the heap */
pthread_mutex_t mutex;
- /** @brief Number of processes that attached the heap */
- unsigned int refcount;
-
/** @brief Chained lists of mdescs */
struct mdesc *next_mdesc;
*/
void *top;
- /** @brief Open file descriptor for the file to which this malloc heap is mapped
- *
- * If this value is negative, MAP_ANONYMOUS memory is used.
- *
- * Also note that it may change each time the region is mapped and unmapped. */
- int fd;
-
/* @brief Instrumentation */
struct mstats heapstats;
};
/* Bits to look at in the malloc descriptor flags word */
#define MMALLOC_DEVZERO (1 << 0) /* Have mapped to /dev/zero */
-#define MMALLOC_ANONYMOUS (1 << 1) /* Use anonymous mapping */
-#define MMALLOC_INITIALIZED (1 << 2) /* Initialized mmalloc */
+#define MMALLOC_INITIALIZED (1 << 1) /* Initialized mmalloc */
/* A default malloc descriptor for the single sbrk() managed region. */
XBT_PUBLIC_DATA struct mdesc* __mmalloc_default_mdp;
-/* Remap a mmalloc region that was previously mapped. */
-
-XBT_PUBLIC void* __mmalloc_remap_core(const s_xbt_mheap_t* mdp);
-
XBT_PUBLIC void* mmorecore(struct mdesc* mdp, ssize_t size);
/** Thread-safety (if the mutex is already created)
XBT_INFO("Allocating a new heap");
unsigned long mask = ~((unsigned long)xbt_pagesize - 1);
auto* addr = reinterpret_cast<void*>(((unsigned long)sbrk(0) + BUFFSIZE) & mask);
- heapA = xbt_mheap_new(-1, addr);
+ heapA = xbt_mheap_new(addr, 0);
if (heapA == nullptr) {
perror("attach 1 failed");
fprintf(stderr, "bye\n");
