The CMA debugfs interface is useful to retrieve basic information out of the
different CMA areas and to test allocation/release in each of the areas.
-Each CMA zone represents a directory under <debugfs>/cma/, indexed by the
-kernel's CMA index. So the first CMA zone would be:
+Each CMA area represents a directory under <debugfs>/cma/, represented by
+its CMA name like below:
- <debugfs>/cma/cma-0
+ <debugfs>/cma/<cma_name>
The structure of the files created under that directory is as follows:
- [RO] bitmap: The bitmap of page states in the zone.
- [WO] alloc: Allocate N pages from that CMA area. For example::
- echo 5 > <debugfs>/cma/cma-2/alloc
+ echo 5 > <debugfs>/cma/<cma_name>/alloc
-would try to allocate 5 pages from the cma-2 area.
+would try to allocate 5 pages from the 'cma_name' area.
- [WO] free: Free N pages from that CMA area, similar to the above.
static void cma_debugfs_add_one(struct cma *cma, struct dentry *root_dentry)
{
struct dentry *tmp;
- char name[CMA_MAX_NAME];
- scnprintf(name, sizeof(name), "cma-%s", cma->name);
-
- tmp = debugfs_create_dir(name, root_dentry);
+ tmp = debugfs_create_dir(cma->name, root_dentry);
debugfs_create_file("alloc", 0200, tmp, cma, &cma_alloc_fops);
debugfs_create_file("free", 0200, tmp, cma, &cma_free_fops);