| Message ID | 1589764857-6800-7-git-send-email-iamjoonsoo.kim@lge.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clean-up the migration target allocation functions | expand |
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()?
2020년 5월 22일 (금) 오전 7:19, Mike Kravetz <mike.kravetz@oracle.com>님이 작성: > > 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. With the following patches, in some cases, ac->gfp_mask is set up once and used many times. If we modify ac->gfp_mask in place, there would be side-effect. > Does dequeue_huge_page_vma() need to be modified so that it will set > ac.__gfp_mask before calling dequeue_huge_page_nodemask()? Good catch! Will change! Thanks.
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 */