2020-08-07 09:15:26

by Wei Yang

Subject: [PATCH 09/10] mm/hugetlb: narrow the hugetlb_lock protection area during preparing huge page

set_hugetlb_cgroup_[rsvd] just manipulate page local data, which is not
necessary to be protected by hugetlb_lock.

Let's take this out.

Signed-off-by: Wei Yang <[email protected]>
---
mm/hugetlb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9473eb6800e9..1f2010c9dd8d 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1494,9 +1494,9 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
{
INIT_LIST_HEAD(&page->lru);
set_compound_page_dtor(page, HUGETLB_PAGE_DTOR);
- spin_lock(&hugetlb_lock);
set_hugetlb_cgroup(page, NULL);
set_hugetlb_cgroup_rsvd(page, NULL);
+ spin_lock(&hugetlb_lock);
h->nr_huge_pages++;
h->nr_huge_pages_node[nid]++;
spin_unlock(&hugetlb_lock);
--
2.20.1 (Apple Git-117)

2020-08-07 13:13:27

by Baoquan He

Subject: Re: [PATCH 09/10] mm/hugetlb: narrow the hugetlb_lock protection area during preparing huge page

On 08/07/20 at 05:12pm, Wei Yang wrote:
> set_hugetlb_cgroup_[rsvd] just manipulate page local data, which is not
> necessary to be protected by hugetlb_lock.
>
> Let's take this out.
>
> Signed-off-by: Wei Yang <[email protected]>
> ---
> mm/hugetlb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 9473eb6800e9..1f2010c9dd8d 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1494,9 +1494,9 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
> {
> INIT_LIST_HEAD(&page->lru);
> set_compound_page_dtor(page, HUGETLB_PAGE_DTOR);
> - spin_lock(&hugetlb_lock);
> set_hugetlb_cgroup(page, NULL);
> set_hugetlb_cgroup_rsvd(page, NULL);
> + spin_lock(&hugetlb_lock);

Looks good to me.

Reviewed-by: Baoquan He <[email protected]>

> h->nr_huge_pages++;
> h->nr_huge_pages_node[nid]++;
> spin_unlock(&hugetlb_lock);
> --
> 2.20.1 (Apple Git-117)
>
>

2020-08-10 23:11:36

by Mike Kravetz

Subject: Re: [PATCH 09/10] mm/hugetlb: narrow the hugetlb_lock protection area during preparing huge page

On 8/7/20 2:12 AM, Wei Yang wrote:
> set_hugetlb_cgroup_[rsvd] just manipulate page local data, which is not
> necessary to be protected by hugetlb_lock.
>
> Let's take this out.
>
> Signed-off-by: Wei Yang <[email protected]>

Thanks!

Reviewed-by: Mike Kravetz <[email protected]>

--
Mike Kravetz