From: Mike Kravetz <mike.kravetz@oracle.com>
To: js1304@gmail.com, Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
kernel-team@lge.com, Vlastimil Babka <vbabka@suse.cz>,
Christoph Hellwig <hch@infradead.org>,
Roman Gushchin <guro@fb.com>,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Michal Hocko <mhocko@suse.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: Re: [PATCH 06/11] mm/hugetlb: do not modify user provided gfp_mask
Date: Thu, 21 May 2020 15:19:19 -0700 [thread overview]
Message-ID: <027b9f05-4a24-e69c-eafa-dbf7cca3ac4e@oracle.com> (raw)
In-Reply-To: <1589764857-6800-7-git-send-email-iamjoonsoo.kim@lge.com>
On 5/17/20 6:20 PM, js1304@gmail.com wrote:
> From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
>
> It's not good practice to modify user input. Instead of using it to
> build correct gfp_mask for APIs, this patch introduces another gfp_mask
> field, __gfp_mask, for internal usage.
Modifying the flags as is done in the existing code does not bother me
too much, but that is just my opinion. Adding __gfp_mask for modifications
is fine with me if others think it is a good thing.
Does dequeue_huge_page_vma() need to be modified so that it will set
ac.__gfp_mask before calling dequeue_huge_page_nodemask()?
--
Mike Kravetz
>
> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
> ---
> mm/hugetlb.c | 15 ++++++++-------
> mm/internal.h | 2 ++
> 2 files changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 53edd02..5f43b7e 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1069,15 +1069,15 @@ static struct page *dequeue_huge_page_nodemask(struct hstate *h,
> struct zoneref *z;
> int node = NUMA_NO_NODE;
>
> - zonelist = node_zonelist(ac->nid, ac->gfp_mask);
> + zonelist = node_zonelist(ac->nid, ac->__gfp_mask);
>
> retry_cpuset:
> cpuset_mems_cookie = read_mems_allowed_begin();
> for_each_zone_zonelist_nodemask(zone, z, zonelist,
> - gfp_zone(ac->gfp_mask), ac->nmask) {
> + gfp_zone(ac->__gfp_mask), ac->nmask) {
> struct page *page;
>
> - if (!cpuset_zone_allowed(zone, ac->gfp_mask))
> + if (!cpuset_zone_allowed(zone, ac->__gfp_mask))
> continue;
> /*
> * no need to ask again on the same node. Pool is node rather than
> @@ -1952,7 +1952,7 @@ static struct page *alloc_migrate_huge_page(struct hstate *h,
> if (hstate_is_gigantic(h))
> return NULL;
>
> - page = alloc_fresh_huge_page(h, ac->gfp_mask,
> + page = alloc_fresh_huge_page(h, ac->__gfp_mask,
> ac->nid, ac->nmask, NULL);
> if (!page)
> return NULL;
> @@ -1990,9 +1990,10 @@ struct page *alloc_buddy_huge_page_with_mpol(struct hstate *h,
> struct page *alloc_huge_page_nodemask(struct hstate *h,
> struct alloc_control *ac)
> {
> - ac->gfp_mask |= htlb_alloc_mask(h);
> + ac->__gfp_mask = htlb_alloc_mask(h);
> + ac->__gfp_mask |= ac->gfp_mask;
> if (ac->thisnode && ac->nid != NUMA_NO_NODE)
> - ac->gfp_mask |= __GFP_THISNODE;
> + ac->__gfp_mask |= __GFP_THISNODE;
>
> spin_lock(&hugetlb_lock);
> if (h->free_huge_pages - h->resv_huge_pages > 0) {
> @@ -2011,7 +2012,7 @@ struct page *alloc_huge_page_nodemask(struct hstate *h,
> * will not come from CMA area
> */
> if (ac->skip_cma)
> - ac->gfp_mask &= ~__GFP_MOVABLE;
> + ac->__gfp_mask &= ~__GFP_MOVABLE;
>
> return alloc_migrate_huge_page(h, ac);
> }
> diff --git a/mm/internal.h b/mm/internal.h
> index 6b6507e..3239d71 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -620,6 +620,8 @@ struct alloc_control {
> gfp_t gfp_mask;
> bool thisnode;
> bool skip_cma;
> +
> + gfp_t __gfp_mask; /* Used internally in API implementation */
> };
>
> #endif /* __MM_INTERNAL_H */
>
next prev parent reply other threads:[~2020-05-21 22:19 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-18 1:20 [PATCH 00/11] clean-up the migration target allocation functions js1304
2020-05-18 1:20 ` [PATCH 01/11] mm/page_isolation: prefer the node of the source page js1304
2020-05-21 0:37 ` Roman Gushchin
2020-05-21 1:18 ` Joonsoo Kim
2020-05-27 6:45 ` Joonsoo Kim
2020-05-18 1:20 ` [PATCH 02/11] mm/migrate: move migration helper from .h to .c js1304
2020-05-21 18:17 ` Mike Kravetz
2020-05-18 1:20 ` [PATCH 03/11] mm/hugetlb: introduce alloc_control structure to simplify migration target allocation APIs js1304
2020-05-21 0:43 ` Roman Gushchin
2020-05-21 1:20 ` Joonsoo Kim
2020-05-21 18:57 ` Mike Kravetz
2020-05-22 5:52 ` Joonsoo Kim
2020-05-18 1:20 ` [PATCH 04/11] mm/hugetlb: unify hugetlb migration callback function js1304
2020-05-21 0:46 ` Roman Gushchin
2020-05-21 1:22 ` Joonsoo Kim
2020-05-21 20:54 ` Mike Kravetz
2020-05-22 7:38 ` Joonsoo Kim
2020-05-18 1:20 ` [PATCH 05/11] mm/hugetlb: make hugetlb migration target allocation APIs CMA aware js1304
2020-05-21 21:43 ` Mike Kravetz
2020-05-18 1:20 ` [PATCH 06/11] mm/hugetlb: do not modify user provided gfp_mask js1304
2020-05-21 22:19 ` Mike Kravetz [this message]
2020-05-22 7:42 ` Joonsoo Kim
2020-05-18 1:20 ` [PATCH 07/11] mm/migrate: change the interface of the migration target alloc/free functions js1304
2020-05-18 1:20 ` [PATCH 08/11] mm/migrate: make standard migration target allocation functions js1304
2020-05-18 1:20 ` [PATCH 09/11] mm/gup: use standard migration target allocation function js1304
2020-05-18 1:20 ` [PATCH 10/11] mm/mempolicy: " js1304
2020-05-18 1:20 ` [PATCH 11/11] mm/page_alloc: use standard migration target allocation function directly js1304
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=027b9f05-4a24-e69c-eafa-dbf7cca3ac4e@oracle.com \
--to=mike.kravetz@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=guro@fb.com \
--cc=hch@infradead.org \
--cc=iamjoonsoo.kim@lge.com \
--cc=js1304@gmail.com \
--cc=kernel-team@lge.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.com \
--cc=n-horiguchi@ah.jp.nec.com \
--cc=vbabka@suse.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).