mm/cma_debug.c: remove static scoped cma_debugfs_root

Currently cma_debugfs_root is static storage.  That is unnecessary since
it will be only used by next cma_debugfs_add_one().  We can just pass it
to following calling to save thisspace.  Also remove useless idx
parameter.

Link: http://lkml.kernel.org/r/20190221040130.8940-1-zbestahu@gmail.com
Signed-off-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/cma_debug.c b/mm/cma_debug.c
index b55f28f..8d7b2fd 100644 (file)
--- a/mm/cma_debug.c
+++ b/mm/cma_debug.c
@@ -21,8 +21,6 @@ struct cma_mem {
        unsigned long n;
 };
 
-static struct dentry *cma_debugfs_root;
-
 static int cma_debugfs_get(void *data, u64 *val)
 {
        unsigned long *p = data;
@@ -162,7 +160,7 @@ static int cma_alloc_write(void *data, u64 val)
 }
 DEFINE_SIMPLE_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n");
 
-static void cma_debugfs_add_one(struct cma *cma, int idx)
+static void cma_debugfs_add_one(struct cma *cma, struct dentry *root_dentry)
 {
        struct dentry *tmp;
        char name[16];
@@ -170,7 +168,7 @@ static void cma_debugfs_add_one(struct cma *cma, int idx)
 
        scnprintf(name, sizeof(name), "cma-%s", cma->name);
 
-       tmp = debugfs_create_dir(name, cma_debugfs_root);
+       tmp = debugfs_create_dir(name, root_dentry);
 
        debugfs_create_file("alloc", 0200, tmp, cma, &cma_alloc_fops);
        debugfs_create_file("free", 0200, tmp, cma, &cma_free_fops);
@@ -188,12 +186,13 @@ static void cma_debugfs_add_one(struct cma *cma, int idx)
 
 static int __init cma_debugfs_init(void)
 {
+       struct dentry *cma_debugfs_root;
        int i;
 
        cma_debugfs_root = debugfs_create_dir("cma", NULL);
 
        for (i = 0; i < cma_area_count; i++)
-               cma_debugfs_add_one(&cma_areas[i], i);
+               cma_debugfs_add_one(&cma_areas[i], cma_debugfs_root);
 
        return 0;
 }