[PATCH v2 1/4] mm/sparse: Clean up the obsolete code comment

[Baoquan He]

The code comment above sparse_add_one_section() is obsolete and
incorrect, clean it up and write new one.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
---
v1-v2:
  Add comments to explain what the returned value means for
  each error code.

 mm/sparse.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/mm/sparse.c b/mm/sparse.c
index 69904aa6165b..b2111f996aa6 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -685,9 +685,18 @@ static void free_map_bootmem(struct page *memmap)
 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
 
 /*
- * returns the number of sections whose mem_maps were properly
- * set.  If this is <=0, then that means that the passed-in
- * map was not consumed and must be freed.
+ * sparse_add_one_section - add a memory section
+ * @nid: The node to add section on
+ * @start_pfn: start pfn of the memory range
+ * @altmap: device page map
+ *
+ * This is only intended for hotplug.
+ *
+ * Returns:
+ *   0 on success.
+ *   Other error code on failure:
+ *     - -EEXIST - section has been present.
+ *     - -ENOMEM - out of memory.
  */
 int __meminit sparse_add_one_section(int nid, unsigned long start_pfn,
 				     struct vmem_altmap *altmap)
-- 
2.17.2