return mem;
}
-void *smpi_shared_malloc(size_t size, const char *file, int line)
+void *smpi_shared_malloc_local(size_t size, const char *file, int line)
{
void* mem;
- if (size > 0 && smpi_cfg_shared_malloc == shmalloc_local) {
- smpi_source_location loc(file, line);
- auto res = allocs.insert(std::make_pair(loc, shared_data_t()));
- auto data = res.first;
- if (res.second) {
- // The insertion did not take place.
- // Generate a shared memory name from the address of the shared_data:
- char shmname[32]; // cannot be longer than PSHMNAMLEN = 31 on Mac OS X (shm_open raises ENAMETOOLONG otherwise)
- snprintf(shmname, 31, "/shmalloc%p", &*data);
- int fd = shm_open(shmname, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
- if (fd < 0) {
- if (errno == EEXIST)
- xbt_die("Please cleanup /dev/shm/%s", shmname);
- else
- xbt_die("An unhandled error occurred while opening %s. shm_open: %s", shmname, strerror(errno));
- }
- data->second.fd = fd;
- data->second.count = 1;
- mem = shm_map(fd, size, &*data);
- if (shm_unlink(shmname) < 0) {
- XBT_WARN("Could not early unlink %s. shm_unlink: %s", shmname, strerror(errno));
- }
- XBT_DEBUG("Mapping %s at %p through %d", shmname, mem, fd);
- } else {
- mem = shm_map(data->second.fd, size, &*data);
- data->second.count++;
+ smpi_source_location loc(file, line);
+ auto res = allocs.insert(std::make_pair(loc, shared_data_t()));
+ auto data = res.first;
+ if (res.second) {
+ // The insertion did not take place.
+ // Generate a shared memory name from the address of the shared_data:
+ char shmname[32]; // cannot be longer than PSHMNAMLEN = 31 on Mac OS X (shm_open raises ENAMETOOLONG otherwise)
+ snprintf(shmname, 31, "/shmalloc%p", &*data);
+ int fd = shm_open(shmname, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+ if (fd < 0) {
+ if (errno == EEXIST)
+ xbt_die("Please cleanup /dev/shm/%s", shmname);
+ else
+ xbt_die("An unhandled error occurred while opening %s. shm_open: %s", shmname, strerror(errno));
}
- XBT_DEBUG("Shared malloc %zu in %p (metadata at %p)", size, mem, &*data);
-
- } else if (smpi_cfg_shared_malloc == shmalloc_global) {
- /* First reserve memory area */
- mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
-
- xbt_assert(mem != MAP_FAILED, "Failed to allocate %luMiB of memory. Run \"sysctl vm.overcommit_memory=1\" as root "
- "to allow big allocations.\n",
- (unsigned long)(size >> 20));
-
- /* Create bogus file if not done already */
- if (smpi_shared_malloc_bogusfile == -1) {
- /* Create a fd to a new file on disk, make it smpi_shared_malloc_blocksize big, and unlink it.
- * It still exists in memory but not in the file system (thus it cannot be leaked). */
- smpi_shared_malloc_blocksize = static_cast<unsigned long>(xbt_cfg_get_double("smpi/shared-malloc-blocksize"));
- XBT_DEBUG("global shared allocation. Blocksize %lu", smpi_shared_malloc_blocksize);
- char* name = xbt_strdup("/tmp/simgrid-shmalloc-XXXXXX");
- smpi_shared_malloc_bogusfile = mkstemp(name);
- unlink(name);
- xbt_free(name);
- char* dumb = (char*)calloc(1, smpi_shared_malloc_blocksize);
- ssize_t err = write(smpi_shared_malloc_bogusfile, dumb, smpi_shared_malloc_blocksize);
- if(err<0)
- xbt_die("Could not write bogus file for shared malloc");
- xbt_free(dumb);
+ data->second.fd = fd;
+ data->second.count = 1;
+ mem = shm_map(fd, size, &*data);
+ if (shm_unlink(shmname) < 0) {
+ XBT_WARN("Could not early unlink %s. shm_unlink: %s", shmname, strerror(errno));
}
+ XBT_DEBUG("Mapping %s at %p through %d", shmname, mem, fd);
+ } else {
+ mem = shm_map(data->second.fd, size, &*data);
+ data->second.count++;
+ }
+ XBT_DEBUG("Shared malloc %zu in %p (metadata at %p)", size, mem, &*data);
+ return mem;
+}
- /* Map the bogus file in place of the anonymous memory */
+// Align functions, from http://stackoverflow.com/questions/4840410/how-to-align-a-pointer-in-c
+#define PAGE_SIZE 0x1000
+#define ALIGN_UP(n, align) (((n) + (align)-1) & -(align))
+#define ALIGN_DOWN(n, align) ((n) & -(align))
+
+void *smpi_shared_malloc_global__(size_t size, const char *file, int line, int *shared_block_offsets, int nb_shared_blocks) {
+ void *mem;
+ xbt_assert(smpi_shared_malloc_blocksize % PAGE_SIZE == 0, "The block size of shared malloc should be a multiple of the page size.");
+ /* First reserve memory area */
+ mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+ xbt_assert(mem != MAP_FAILED, "Failed to allocate %luMiB of memory. Run \"sysctl vm.overcommit_memory=1\" as root "
+ "to allow big allocations.\n",
+ (unsigned long)(size >> 20));
+
+ /* Create bogus file if not done already */
+ if (smpi_shared_malloc_bogusfile == -1) {
+ /* Create a fd to a new file on disk, make it smpi_shared_malloc_blocksize big, and unlink it.
+ * It still exists in memory but not in the file system (thus it cannot be leaked). */
+ smpi_shared_malloc_blocksize = static_cast<unsigned long>(xbt_cfg_get_double("smpi/shared-malloc-blocksize"));
+ XBT_DEBUG("global shared allocation. Blocksize %lu", smpi_shared_malloc_blocksize);
+ char* name = xbt_strdup("/tmp/simgrid-shmalloc-XXXXXX");
+ smpi_shared_malloc_bogusfile = mkstemp(name);
+ unlink(name);
+ xbt_free(name);
+ char* dumb = (char*)calloc(1, smpi_shared_malloc_blocksize);
+ ssize_t err = write(smpi_shared_malloc_bogusfile, dumb, smpi_shared_malloc_blocksize);
+ if(err<0)
+ xbt_die("Could not write bogus file for shared malloc");
+ xbt_free(dumb);
+ }
+
+ /* Map the bogus file in place of the anonymous memory */
+ for(int i_block = 0; i_block < nb_shared_blocks; i_block ++) {
+ int start_offset = shared_block_offsets[2*i_block];
+ int stop_offset = shared_block_offsets[2*i_block+1];
+ int start_block_offset = ALIGN_UP(start_offset, smpi_shared_malloc_blocksize);
+ int stop_block_offset = ALIGN_DOWN(stop_offset, smpi_shared_malloc_blocksize);
unsigned int i;
- for (i = 0; i < size / smpi_shared_malloc_blocksize; i++) {
+ for (i = start_block_offset / smpi_shared_malloc_blocksize; i < stop_block_offset / smpi_shared_malloc_blocksize; i++) {
void* pos = (void*)((unsigned long)mem + i * smpi_shared_malloc_blocksize);
void* res = mmap(pos, smpi_shared_malloc_blocksize, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED | MAP_POPULATE,
smpi_shared_malloc_bogusfile, 0);
"You can also try using the sysctl vm.max_map_count",
strerror(errno));
}
- if (size % smpi_shared_malloc_blocksize) {
- void* pos = (void*)((unsigned long)mem + i * smpi_shared_malloc_blocksize);
- void* res = mmap(pos, size % smpi_shared_malloc_blocksize, PROT_READ | PROT_WRITE,
- MAP_FIXED | MAP_SHARED | MAP_POPULATE, smpi_shared_malloc_bogusfile, 0);
+ int low_page_start_offset = ALIGN_UP(start_offset, PAGE_SIZE);
+ int low_page_stop_offset = start_block_offset < ALIGN_DOWN(stop_offset, PAGE_SIZE) ? start_block_offset : ALIGN_DOWN(stop_offset, PAGE_SIZE);
+ if(low_page_start_offset < low_page_stop_offset) {
+ void* pos = (void*)((unsigned long)mem + low_page_start_offset);
+ void* res = mmap(pos, low_page_stop_offset-low_page_start_offset, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED | MAP_POPULATE,
+ smpi_shared_malloc_bogusfile, 0);
xbt_assert(res == pos, "Could not map folded virtual memory (%s). Do you perhaps need to increase the "
"size of the mapped file using --cfg=smpi/shared-malloc-blocksize=newvalue (default 1048576) ?"
"You can also try using the sysctl vm.max_map_count",
strerror(errno));
}
+ if(low_page_stop_offset <= stop_block_offset) {
+ int high_page_stop_offset = stop_offset == size ? size : ALIGN_DOWN(stop_offset, PAGE_SIZE);
+ if(high_page_stop_offset > stop_block_offset) {
+ void* pos = (void*)((unsigned long)mem + stop_block_offset);
+ void* res = mmap(pos, high_page_stop_offset-stop_block_offset, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED | MAP_POPULATE,
+ smpi_shared_malloc_bogusfile, 0);
+ xbt_assert(res == pos, "Could not map folded virtual memory (%s). Do you perhaps need to increase the "
+ "size of the mapped file using --cfg=smpi/shared-malloc-blocksize=newvalue (default 1048576) ?"
+ "You can also try using the sysctl vm.max_map_count",
+ strerror(errno));
+ }
+ }
+ }
+ if(nb_shared_blocks == 1 && shared_block_offsets[0] == 0 && shared_block_offsets[1] == size) {
shared_metadata_t newmeta;
//register metadata for memcpy avoidance
shared_data_key_type* data = (shared_data_key_type*)xbt_malloc(sizeof(shared_data_key_type));
newmeta.size = size;
newmeta.data = data;
allocs_metadata[mem] = newmeta;
+ }
+
+ return mem;
+}
+
+/*
+ * When nb_shared_blocks == -1, default behavior of smpi_shared_malloc: everything is shared.
+ * Otherwise, only the blocks described by shared_block_offsets are shared.
+ * This array contains the offsets (in bytes) of the block to share.
+ * Even indices are the start offsets (included), odd indices are the stop offsets (excluded).
+ * For instance, if shared_block_offsets == {27, 42}, then the elements mem[27], mem[28], ..., mem[41] are shared. The others are not.
+ */
+void *smpi_shared_malloc_global(size_t size, const char *file, int line, int *shared_block_offsets=NULL, int nb_shared_blocks=-1) {
+ int tmp_shared_block_offsets[2];
+ if(nb_shared_blocks == -1) {
+ nb_shared_blocks = 1;
+ shared_block_offsets = tmp_shared_block_offsets;
+ shared_block_offsets[0] = 0;
+ shared_block_offsets[1] = size;
+ }
+ return smpi_shared_malloc_global__(size, file, line, shared_block_offsets, nb_shared_blocks);
+}
+
+void *smpi_shared_malloc(size_t size, const char *file, int line) {
+ void *mem;
+ if (size > 0 && smpi_cfg_shared_malloc == shmalloc_local) {
+ mem = smpi_shared_malloc_local(size, file, line);
+ } else if (smpi_cfg_shared_malloc == shmalloc_global) {
+ mem = smpi_shared_malloc_global(size, file, line);
} else {
mem = xbt_malloc(size);
XBT_DEBUG("Classic malloc %zu in %p", size, mem);
}
-
return mem;
}
