Make smalloc use anonymous memory mmaps
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/smalloc.c b/smalloc.c
index fdf7d22..a925a65 100644
--- a/smalloc.c
+++ b/smalloc.c
@@ -38,7 +38,6 @@
unsigned int free_blocks; /* free blocks */
unsigned int nr_blocks; /* total blocks */
unsigned int next_non_full;
- int fd; /* memory backing fd */
unsigned int mmap_size;
};
@@ -178,14 +177,9 @@
static int add_pool(struct pool *pool, unsigned int alloc_size)
{
- int fd, bitmap_blocks;
- char file[] = "/tmp/.fio_smalloc.XXXXXX";
+ int bitmap_blocks;
void *ptr;
- fd = mkstemp(file);
- if (fd < 0)
- goto out_close;
-
#ifdef SMALLOC_REDZONE
alloc_size += sizeof(unsigned int);
#endif
@@ -202,16 +196,10 @@
pool->nr_blocks = bitmap_blocks;
pool->free_blocks = bitmap_blocks * SMALLOC_BPB;
-#ifdef FIO_HAVE_FALLOCATE
- posix_fallocate(fd, 0, alloc_size);
-#endif
-
- if (ftruncate(fd, alloc_size) < 0)
- goto out_unlink;
-
- ptr = mmap(NULL, alloc_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+ ptr = mmap(NULL, alloc_size, PROT_READ|PROT_WRITE,
+ MAP_SHARED | OS_MAP_ANON, -1, 0);
if (ptr == MAP_FAILED)
- goto out_unlink;
+ goto out_fail;
memset(ptr, 0, alloc_size);
pool->map = ptr;
@@ -219,25 +207,14 @@
pool->lock = fio_mutex_init(1);
if (!pool->lock)
- goto out_unlink;
-
- /*
- * Unlink pool file now. It wont get deleted until the fd is closed,
- * which happens both for cleanup or unexpected quit. This way we
- * don't leave temp files around in case of a crash.
- */
- unlink(file);
- pool->fd = fd;
+ goto out_fail;
nr_pools++;
return 0;
-out_unlink:
+out_fail:
fprintf(stderr, "smalloc: failed adding pool\n");
if (pool->map)
munmap(pool->map, pool->mmap_size);
- unlink(file);
-out_close:
- close(fd);
return 1;
}
@@ -256,7 +233,6 @@
* This will also remove the temporary file we used as a backing
* store, it was already unlinked
*/
- close(pool->fd);
munmap(pool->map, pool->mmap_size);
if (pool->lock)