If the source page being migrated has metadata associated with it, make
sure to reserve the metadata storage when choosing a suitable destination
page from the free list.
Signed-off-by: Alexandru Elisei <[email protected]>
---
mm/compaction.c | 9 +++++++++
mm/internal.h | 1 +
2 files changed, 10 insertions(+)
diff --git a/mm/compaction.c b/mm/compaction.c
index cc0139fa0cb0..af2ee3085623 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -570,6 +570,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
bool locked = false;
unsigned long blockpfn = *start_pfn;
unsigned int order;
+ int ret;
/* Strict mode is for isolation, speed is secondary */
if (strict)
@@ -626,6 +627,11 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
/* Found a free page, will break it into order-0 pages */
order = buddy_order(page);
+ if (metadata_storage_enabled() && cc->reserve_metadata) {
+ ret = reserve_metadata_storage(page, order, cc->gfp_mask);
+ if (ret)
+ goto isolate_fail;
+ }
isolated = __isolate_free_page(page, order);
if (!isolated)
break;
@@ -1757,6 +1763,9 @@ static struct folio *compaction_alloc(struct folio *src, unsigned long data)
struct compact_control *cc = (struct compact_control *)data;
struct folio *dst;
+ if (metadata_storage_enabled())
+ cc->reserve_metadata = folio_has_metadata(src);
+
if (list_empty(&cc->freepages)) {
isolate_freepages(cc);
diff --git a/mm/internal.h b/mm/internal.h
index d28ac0085f61..046cc264bfbe 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -492,6 +492,7 @@ struct compact_control {
*/
bool alloc_contig; /* alloc_contig_range allocation */
bool source_has_metadata; /* source pages have associated metadata */
+ bool reserve_metadata;
};
/*
--
2.41.0
Hi Alexandru,
On Wed, Aug 23, 2023 at 6:16 AM Alexandru Elisei
<[email protected]> wrote:
>
> If the source page being migrated has metadata associated with it, make
> sure to reserve the metadata storage when choosing a suitable destination
> page from the free list.
>
> Signed-off-by: Alexandru Elisei <[email protected]>
> ---
> mm/compaction.c | 9 +++++++++
> mm/internal.h | 1 +
> 2 files changed, 10 insertions(+)
>
> diff --git a/mm/compaction.c b/mm/compaction.c
> index cc0139fa0cb0..af2ee3085623 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -570,6 +570,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> bool locked = false;
> unsigned long blockpfn = *start_pfn;
> unsigned int order;
> + int ret;
>
> /* Strict mode is for isolation, speed is secondary */
> if (strict)
> @@ -626,6 +627,11 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
>
> /* Found a free page, will break it into order-0 pages */
> order = buddy_order(page);
> + if (metadata_storage_enabled() && cc->reserve_metadata) {
> + ret = reserve_metadata_storage(page, order, cc->gfp_mask);
At this point the zone lock is held and preemption is disabled, which
makes it invalid to call reserve_metadata_storage.
Peter
> + if (ret)
> + goto isolate_fail;
> + }
> isolated = __isolate_free_page(page, order);
> if (!isolated)
> break;
> @@ -1757,6 +1763,9 @@ static struct folio *compaction_alloc(struct folio *src, unsigned long data)
> struct compact_control *cc = (struct compact_control *)data;
> struct folio *dst;
>
> + if (metadata_storage_enabled())
> + cc->reserve_metadata = folio_has_metadata(src);
> +
> if (list_empty(&cc->freepages)) {
> isolate_freepages(cc);
>
> diff --git a/mm/internal.h b/mm/internal.h
> index d28ac0085f61..046cc264bfbe 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -492,6 +492,7 @@ struct compact_control {
> */
> bool alloc_contig; /* alloc_contig_range allocation */
> bool source_has_metadata; /* source pages have associated metadata */
> + bool reserve_metadata;
> };
>
> /*
> --
> 2.41.0
>
Hi Peter,
On Mon, Nov 20, 2023 at 08:49:32PM -0800, Peter Collingbourne wrote:
> Hi Alexandru,
>
> On Wed, Aug 23, 2023 at 6:16 AM Alexandru Elisei
> <[email protected]> wrote:
> >
> > If the source page being migrated has metadata associated with it, make
> > sure to reserve the metadata storage when choosing a suitable destination
> > page from the free list.
> >
> > Signed-off-by: Alexandru Elisei <[email protected]>
> > ---
> > mm/compaction.c | 9 +++++++++
> > mm/internal.h | 1 +
> > 2 files changed, 10 insertions(+)
> >
> > diff --git a/mm/compaction.c b/mm/compaction.c
> > index cc0139fa0cb0..af2ee3085623 100644
> > --- a/mm/compaction.c
> > +++ b/mm/compaction.c
> > @@ -570,6 +570,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> > bool locked = false;
> > unsigned long blockpfn = *start_pfn;
> > unsigned int order;
> > + int ret;
> >
> > /* Strict mode is for isolation, speed is secondary */
> > if (strict)
> > @@ -626,6 +627,11 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
> >
> > /* Found a free page, will break it into order-0 pages */
> > order = buddy_order(page);
> > + if (metadata_storage_enabled() && cc->reserve_metadata) {
> > + ret = reserve_metadata_storage(page, order, cc->gfp_mask);
>
> At this point the zone lock is held and preemption is disabled, which
> makes it invalid to call reserve_metadata_storage.
You are correct, I missed that. I dropped reserving tag storage during
compaction in the next iteration, so fortunately I unintentionally fixed
it.
Thanks,
Alex
>
> Peter
>
> > + if (ret)
> > + goto isolate_fail;
> > + }
> > isolated = __isolate_free_page(page, order);
> > if (!isolated)
> > break;
> > @@ -1757,6 +1763,9 @@ static struct folio *compaction_alloc(struct folio *src, unsigned long data)
> > struct compact_control *cc = (struct compact_control *)data;
> > struct folio *dst;
> >
> > + if (metadata_storage_enabled())
> > + cc->reserve_metadata = folio_has_metadata(src);
> > +
> > if (list_empty(&cc->freepages)) {
> > isolate_freepages(cc);
> >
> > diff --git a/mm/internal.h b/mm/internal.h
> > index d28ac0085f61..046cc264bfbe 100644
> > --- a/mm/internal.h
> > +++ b/mm/internal.h
> > @@ -492,6 +492,7 @@ struct compact_control {
> > */
> > bool alloc_contig; /* alloc_contig_range allocation */
> > bool source_has_metadata; /* source pages have associated metadata */
> > + bool reserve_metadata;
> > };
> >
> > /*
> > --
> > 2.41.0
> >