Clarify documentation relating to mm_users and mm_count, and switch to
kernel-doc syntax.
Signed-off-by: Vegard Nossum <vegard.nos...@oracle.com>
---
include/linux/mm_types.h | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 08d947fc4c59..316c3e1fc226 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -407,8 +407,27 @@ struct mm_struct {
unsigned long task_size; /* size of task vm space */
unsigned long highest_vm_end; /* highest vma end address */
pgd_t * pgd;
- atomic_t mm_users; /* How many users with user
space? */
- atomic_t mm_count; /* How many references to
"struct mm_struct" (users count as 1) */
+
+ /**
+ * @mm_users: The number of users including userspace.
+ *
+ * Use mmget()/mmget_not_zero()/mmput() to modify. When this drops
+ * to 0 (i.e. when the task exits and there are no other temporary
+ * reference holders), we also release a reference on @mm_count
+ * (which may then free the &struct mm_struct if @mm_count also
+ * drops to 0).
+ */
+ atomic_t mm_users;
+
+ /**
+ * @mm_count: The number of references to &struct mm_struct
+ * (@mm_users count as 1).
+ *
+ * Use mmgrab()/mmdrop() to modify. When this drops to 0, the
+ * &struct mm_struct is freed.
+ */
+ atomic_t mm_count;
+
atomic_long_t nr_ptes; /* PTE page table pages */
#if CONFIG_PGTABLE_LEVELS > 2
atomic_long_t nr_pmds; /* PMD page table pages */
--
2.11.0.1.gaa10c3f
