diff options
authorJoonsoo Kim <iamjoonsoo.kim@lge.com>2020-08-11 18:37:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-12 10:58:02 -0700
commitbbe88753bd42b1faf1458dde8f58ff1239990436 (patch)
parent41b4dc14ee807cb1bd15e67cad287534046f92dc (diff)
mm/hugetlb: make hugetlb migration callback CMA aware
new_non_cma_page() in gup.c requires to allocate the new page that is not on the CMA area. new_non_cma_page() implements it by using allocation scope APIs. However, there is a work-around for hugetlb. Normal hugetlb page allocation API for migration is alloc_huge_page_nodemask(). It consists of two steps. First is dequeing from the pool. Second is, if there is no available page on the queue, allocating by using the page allocator. new_non_cma_page() can't use this API since first step (deque) isn't aware of scope API to exclude CMA area. So, new_non_cma_page() exports hugetlb internal function for the second step, alloc_migrate_huge_page(), to global scope and uses it directly. This is suboptimal since hugetlb pages on the queue cannot be utilized. This patch tries to fix this situation by making the deque function on hugetlb CMA aware. In the deque function, CMA memory is skipped if PF_MEMALLOC_NOCMA flag is found. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Roman Gushchin <guro@fb.com> Link: http://lkml.kernel.org/r/1596180906-8442-2-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
3 files changed, 10 insertions, 9 deletions
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index d86c82749836..d5cc5f802dd4 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -511,8 +511,6 @@ struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
nodemask_t *nmask, gfp_t gfp_mask);
struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
unsigned long address);
-struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
- int nid, nodemask_t *nmask);
int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
pgoff_t idx);
diff --git a/mm/gup.c b/mm/gup.c
index 6c20c6e37635..c55427beeb26 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1635,11 +1635,7 @@ static struct page *new_non_cma_page(struct page *page, unsigned long private)
struct hstate *h = page_hstate(page);
gfp_mask = htlb_modify_alloc_mask(h, gfp_mask);
- /*
- * We don't want to dequeue from the pool because pool pages will
- * mostly be from the CMA region.
- */
- return alloc_migrate_huge_page(h, gfp_mask, nid, NULL);
+ return alloc_huge_page_nodemask(h, nid, NULL, gfp_mask);
if (PageTransHuge(page)) {
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index eaab9ef88e9d..a301c2d672bf 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -19,6 +19,7 @@
#include <linux/memblock.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
+#include <linux/sched/mm.h>
#include <linux/mmdebug.h>
#include <linux/sched/signal.h>
#include <linux/rmap.h>
@@ -1040,10 +1041,16 @@ static void enqueue_huge_page(struct hstate *h, struct page *page)
static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
struct page *page;
+ bool nocma = !!(current->flags & PF_MEMALLOC_NOCMA);
+ list_for_each_entry(page, &h->hugepage_freelists[nid], lru) {
+ if (nocma && is_migrate_cma_page(page))
+ continue;
- list_for_each_entry(page, &h->hugepage_freelists[nid], lru)
if (!PageHWPoison(page))
+ }
* if 'non-isolated free hugepage' not found on the list,
* the allocation fails.
@@ -1935,7 +1942,7 @@ out_unlock:
return page;
-struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
+static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nmask)
struct page *page;