On 1/24/21 11:36 PM, Matthew Wilcox wrote:
On Sun, Jan 24, 2021 at 11:24:41PM -0500, Waiman Long wrote:
diff --git a/mm/filemap.c b/mm/filemap.c
index 5c9d564317a5..aa0e0fb04670 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -835,6 +835,7 @@ noinline int __add_to_page_cache_locked(struct page *page,
XA_STATE(xas, &mapping->i_pages, offset);
int huge = PageHuge(page);
int error;
+ bool charged = false;
I don't think we need this extra bool.
@@ -896,6 +898,8 @@ noinline int __add_to_page_cache_locked(struct page *page,
if (xas_error(&xas)) {
error = xas_error(&xas);
+ if (charged)
+ mem_cgroup_uncharge(page);
goto error;
}
Better:
- goto error;
+ goto uncharge;
...
+uncharge:
+ if (!huge)
+ mem_cgroup_uncharge(page);
error:
...
That was my original plan. After finding out there was a potentially
conflicting patch in linux-next:
commit 7a02fa97b897 ("secretmem: add memcg accounting")
@@ -839,7 +840,7 @@ noinline int __add_to_page_cache_locked(struct page
*page,
page->mapping = mapping;
page->index = offset;
- if (!huge) {
+ if (!huge && !page_is_secretmem(page)) {
error = mem_cgroup_charge(page, current->mm, gfp);
if (error)
goto error;
Adding a boolean is an easy way out without conflicting it.
Cheers,
Longman
