Re: [PATCH v3 6/8] mm/gup: use a standard migration target allocation callback
2020년 7월 4일 (토) 오전 12:56, Vlastimil Babka 님이 작성:
>
> On 6/23/20 8:13 AM, js1...@gmail.com wrote:
> > From: Joonsoo Kim
> >
> > There is a well-defined migration target allocation callback.
> > It's mostly similar with new_non_cma_page() except considering CMA pages.
> >
> > This patch adds a CMA consideration to the standard migration target
> > allocation callback and use it on gup.c.
> >
> > Signed-off-by: Joonsoo Kim
>
> Acked-by: Vlastimil Babka
>
> But a suggestion below.
>
> > ---
> > mm/gup.c | 57
> > -
> > mm/internal.h | 1 +
> > mm/migrate.c | 4 +++-
> > 3 files changed, 12 insertions(+), 50 deletions(-)
> >
> > diff --git a/mm/gup.c b/mm/gup.c
> > index 15be281..f6124e3 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -1608,56 +1608,15 @@ static bool check_dax_vmas(struct vm_area_struct
> > **vmas, long nr_pages)
> > }
> >
> > #ifdef CONFIG_CMA
> > -static struct page *new_non_cma_page(struct page *page, unsigned long
> > private)
> > +static struct page *alloc_migration_target_non_cma(struct page *page,
> > unsigned long private)
> > {
>
> ...
>
> > + struct migration_target_control mtc = {
> > + .nid = page_to_nid(page),
> > + .gfp_mask = GFP_USER | __GFP_NOWARN,
> > + .skip_cma = true,
> > + };
> >
> > - return __alloc_pages_node(nid, gfp_mask, 0);
> > + return alloc_migration_target(page, (unsigned long));
>
> Do we really need this wrapper? The only user is check_and_migrate_cma_pages
> so
> just opencode it?
This wrapper exists for setting up a different nid for each page.
However, as you suggested in the next reply, we can remove this wrapper if
NUMA_NO_NODE handling is added to the standard function. I will add NUMA_NO_NODE
handling to the standard function and remove this wrapper.
Thanks.
Re: [PATCH v3 6/8] mm/gup: use a standard migration target allocation callback
On 6/23/20 8:13 AM, js1...@gmail.com wrote:
> From: Joonsoo Kim
>
> There is a well-defined migration target allocation callback.
> It's mostly similar with new_non_cma_page() except considering CMA pages.
>
> This patch adds a CMA consideration to the standard migration target
> allocation callback and use it on gup.c.
>
> Signed-off-by: Joonsoo Kim
Acked-by: Vlastimil Babka
But a suggestion below.
> ---
> mm/gup.c | 57 -
> mm/internal.h | 1 +
> mm/migrate.c | 4 +++-
> 3 files changed, 12 insertions(+), 50 deletions(-)
>
> diff --git a/mm/gup.c b/mm/gup.c
> index 15be281..f6124e3 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -1608,56 +1608,15 @@ static bool check_dax_vmas(struct vm_area_struct
> **vmas, long nr_pages)
> }
>
> #ifdef CONFIG_CMA
> -static struct page *new_non_cma_page(struct page *page, unsigned long
> private)
> +static struct page *alloc_migration_target_non_cma(struct page *page,
> unsigned long private)
> {
...
> + struct migration_target_control mtc = {
> + .nid = page_to_nid(page),
> + .gfp_mask = GFP_USER | __GFP_NOWARN,
> + .skip_cma = true,
> + };
>
> - return __alloc_pages_node(nid, gfp_mask, 0);
> + return alloc_migration_target(page, (unsigned long));
Do we really need this wrapper? The only user is check_and_migrate_cma_pages so
just opencode it?
Re: [PATCH v3 6/8] mm/gup: use a standard migration target allocation callback
2020년 6월 25일 (목) 오후 9:08, Michal Hocko 님이 작성: > > On Tue 23-06-20 15:13:46, Joonsoo Kim wrote: > > From: Joonsoo Kim > > > > There is a well-defined migration target allocation callback. > > It's mostly similar with new_non_cma_page() except considering CMA pages. > > > > This patch adds a CMA consideration to the standard migration target > > allocation callback and use it on gup.c. > > We already can express that by a missing __GFP_MOVABLE so I would rather > not introduce a duplication in form of another flag. I replied to this question in a previous email. Thanks.
Re: [PATCH v3 6/8] mm/gup: use a standard migration target allocation callback
On Tue 23-06-20 15:13:46, Joonsoo Kim wrote: > From: Joonsoo Kim > > There is a well-defined migration target allocation callback. > It's mostly similar with new_non_cma_page() except considering CMA pages. > > This patch adds a CMA consideration to the standard migration target > allocation callback and use it on gup.c. We already can express that by a missing __GFP_MOVABLE so I would rather not introduce a duplication in form of another flag. -- Michal Hocko SUSE Labs
[PATCH v3 6/8] mm/gup: use a standard migration target allocation callback
From: Joonsoo Kim
There is a well-defined migration target allocation callback.
It's mostly similar with new_non_cma_page() except considering CMA pages.
This patch adds a CMA consideration to the standard migration target
allocation callback and use it on gup.c.
Signed-off-by: Joonsoo Kim
---
mm/gup.c | 57 -
mm/internal.h | 1 +
mm/migrate.c | 4 +++-
3 files changed, 12 insertions(+), 50 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c
index 15be281..f6124e3 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1608,56 +1608,15 @@ static bool check_dax_vmas(struct vm_area_struct
**vmas, long nr_pages)
}
#ifdef CONFIG_CMA
-static struct page *new_non_cma_page(struct page *page, unsigned long private)
+static struct page *alloc_migration_target_non_cma(struct page *page, unsigned
long private)
{
- /*
-* We want to make sure we allocate the new page from the same node
-* as the source page.
-*/
- int nid = page_to_nid(page);
- /*
-* Trying to allocate a page for migration. Ignore allocation
-* failure warnings. We don't force __GFP_THISNODE here because
-* this node here is the node where we have CMA reservation and
-* in some case these nodes will have really less non movable
-* allocation memory.
-*/
- gfp_t gfp_mask = GFP_USER | __GFP_NOWARN;
-
- if (PageHighMem(page))
- gfp_mask |= __GFP_HIGHMEM;
-
-#ifdef CONFIG_HUGETLB_PAGE
- if (PageHuge(page)) {
- struct hstate *h = page_hstate(page);
-
- /*
-* We don't want to dequeue from the pool because pool pages
will
-* mostly be from the CMA region.
-*/
- return alloc_huge_page_nodemask(h, nid, NULL, gfp_mask, true);
- }
-#endif
- if (PageTransHuge(page)) {
- struct page *thp;
- /*
-* ignore allocation failure warnings
-*/
- gfp_t thp_gfpmask = GFP_TRANSHUGE | __GFP_NOWARN;
-
- /*
-* Remove the movable mask so that we don't allocate from
-* CMA area again.
-*/
- thp_gfpmask &= ~__GFP_MOVABLE;
- thp = __alloc_pages_node(nid, thp_gfpmask, HPAGE_PMD_ORDER);
- if (!thp)
- return NULL;
- prep_transhuge_page(thp);
- return thp;
- }
+ struct migration_target_control mtc = {
+ .nid = page_to_nid(page),
+ .gfp_mask = GFP_USER | __GFP_NOWARN,
+ .skip_cma = true,
+ };
- return __alloc_pages_node(nid, gfp_mask, 0);
+ return alloc_migration_target(page, (unsigned long));
}
static long check_and_migrate_cma_pages(struct task_struct *tsk,
@@ -1719,7 +1678,7 @@ static long check_and_migrate_cma_pages(struct
task_struct *tsk,
for (i = 0; i < nr_pages; i++)
put_page(pages[i]);
- if (migrate_pages(_page_list, new_non_cma_page,
+ if (migrate_pages(_page_list,
alloc_migration_target_non_cma,
NULL, 0, MIGRATE_SYNC, MR_CONTIG_RANGE)) {
/*
* some of the pages failed migration. Do get_user_pages
diff --git a/mm/internal.h b/mm/internal.h
index f725aa8..fb7f7fe 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -619,6 +619,7 @@ struct migration_target_control {
int nid;/* preferred node id */
nodemask_t *nmask;
gfp_t gfp_mask;
+ bool skip_cma;
};
#endif /* __MM_INTERNAL_H */
diff --git a/mm/migrate.c b/mm/migrate.c
index 3afff59..7c4cd74 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1550,7 +1550,7 @@ struct page *alloc_migration_target(struct page *page,
unsigned long private)
if (PageHuge(page)) {
return alloc_huge_page_nodemask(
page_hstate(compound_head(page)), mtc->nid,
- mtc->nmask, gfp_mask, false);
+ mtc->nmask, gfp_mask, mtc->skip_cma);
}
if (PageTransHuge(page)) {
@@ -1561,6 +1561,8 @@ struct page *alloc_migration_target(struct page *page,
unsigned long private)
zidx = zone_idx(page_zone(page));
if (is_highmem_idx(zidx) || zidx == ZONE_MOVABLE)
gfp_mask |= __GFP_HIGHMEM;
+ if (mtc->skip_cma)
+ gfp_mask &= ~__GFP_MOVABLE;
new_page = __alloc_pages_nodemask(gfp_mask, order,
mtc->nid, mtc->nmask);
--
2.7.4
