From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/rmap: correct some obsolete comments of anon_vma
commit 2b575eb64f7a ("mm: convert anon_vma->lock to a mutex") changed
spinlock used to serialize access to vma list to mutex. And further, the
commit 5a505085f043 ("mm/rmap: Convert the struct anon_vma::mutex to an
rwsem") converted the mutex to an rwsem for solving scalability problem.
So replace spinlock with rwsem to make comment uptodate.
Link: https://lkml.kernel.org/r/20210123072459.25903-1-linmiaohe@xxxxxxxxxx
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/rmap.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/mm/rmap.c~mm-rmap-correct-some-obsolete-comments-of-anon_vma
+++ a/mm/rmap.c
@@ -168,7 +168,7 @@ static void anon_vma_chain_link(struct v
*
* Anon-vma allocations are very subtle, because we may have
* optimistically looked up an anon_vma in page_lock_anon_vma_read()
- * and that may actually touch the spinlock even in the newly
+ * and that may actually touch the rwsem even in the newly
* allocated vma (it depends on RCU to make sure that the
* anon_vma isn't actually destroyed).
*
@@ -359,7 +359,7 @@ int anon_vma_fork(struct vm_area_struct
goto out_error_free_anon_vma;
/*
- * The root anon_vma's spinlock is the lock actually used when we
+ * The root anon_vma's rwsem is the lock actually used when we
* lock any of the anon_vmas in this anon_vma tree.
*/
anon_vma->root = pvma->anon_vma->root;
_
