return mem;
}
-void *smpi_shared_malloc_global(size_t size, const char *file, int line) {
+// 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);
}
/* Map the bogus file in place of the anonymous memory */
- unsigned int i;
- for (i = 0; i < size / 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);
- 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 (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);
- 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));
+ 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];
+// fprintf(stderr, "shared block 0x%x - 0x%x\n", start_offset, stop_offset);
+ 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 = start_block_offset / smpi_shared_malloc_blocksize; i < stop_block_offset / smpi_shared_malloc_blocksize; i++) {
+// fprintf(stderr, "\tmmap:for 0x%x - 0x%x\n", i*smpi_shared_malloc_blocksize, smpi_shared_malloc_blocksize);
+ 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);
+ 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));
+ }
+ 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) {
+// fprintf(stderr, "\tmmap:low 0x%x - 0x%x\n", low_page_start_offset, low_page_stop_offset-low_page_start_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) {
+// fprintf(stderr, "\tmmap:high 0x%x - 0x%x\n", stop_block_offset, 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));
+ }
+ }
}
- 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));
- data->second.fd = -1;
- data->second.count = 1;
- newmeta.size = size;
- newmeta.data = data;
- allocs_metadata[mem] = newmeta;
+ 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));
+ data->second.fd = -1;
+ data->second.count = 1;
+ 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) {
