Re: [PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
On Sat, 30 Aug 2014 20:41:23 +0400 Konstantin Khlebnikov wrote: > This patch replaces checking AS_BALLOON_MAP in page->mapping->flags > with PageBalloon which is stored directly in the struct page. > All code of balloon_compaction now under CONFIG_MEMORY_BALLOON. argh, now the bogus Kconfig/Makefile changes get removed again. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
On Sat, 30 Aug 2014 20:41:23 +0400 Konstantin Khlebnikov koc...@gmail.com wrote: This patch replaces checking AS_BALLOON_MAP in page-mapping-flags with PageBalloon which is stored directly in the struct page. All code of balloon_compaction now under CONFIG_MEMORY_BALLOON. argh, now the bogus Kconfig/Makefile changes get removed again. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
On Sat, Aug 30, 2014 at 08:41:23PM +0400, Konstantin Khlebnikov wrote:
> From: Konstantin Khlebnikov
>
> This patch replaces checking AS_BALLOON_MAP in page->mapping->flags
> with PageBalloon which is stored directly in the struct page.
> All code of balloon_compaction now under CONFIG_MEMORY_BALLOON.
>
> Signed-off-by: Konstantin Khlebnikov
> ---
> drivers/virtio/Kconfig |1
> include/linux/balloon_compaction.h | 135
> ++--
> mm/Kconfig |2 -
> mm/Makefile|3 +
> mm/balloon_compaction.c|7 +-
> mm/compaction.c|9 +-
> mm/migrate.c |6 +-
> mm/vmscan.c|2 -
> 8 files changed, 39 insertions(+), 126 deletions(-)
>
> diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
> index c6683f2..00b2286 100644
> --- a/drivers/virtio/Kconfig
> +++ b/drivers/virtio/Kconfig
> @@ -25,6 +25,7 @@ config VIRTIO_PCI
> config VIRTIO_BALLOON
> tristate "Virtio balloon driver"
> depends on VIRTIO
> + select MEMORY_BALLOON
> ---help---
>This driver supports increasing and decreasing the amount
>of memory within a KVM guest.
> diff --git a/include/linux/balloon_compaction.h
> b/include/linux/balloon_compaction.h
> index 284fc1d..09f8c5a 100644
> --- a/include/linux/balloon_compaction.h
> +++ b/include/linux/balloon_compaction.h
> @@ -46,6 +46,8 @@
> #include
> #include
>
> +#ifdef CONFIG_MEMORY_BALLOON
> +
> /*
> * Balloon device information descriptor.
> * This struct is used to allow the common balloon compaction interface
> @@ -93,91 +95,6 @@ static inline void balloon_page_free(struct page *page)
> __free_page(page);
> }
>
> -#ifdef CONFIG_BALLOON_COMPACTION
> -extern bool balloon_page_isolate(struct page *page);
> -extern void balloon_page_putback(struct page *page);
> -extern int balloon_page_migrate(struct page *newpage,
> - struct page *page, enum migrate_mode mode);
> -extern struct address_space
> -*balloon_mapping_alloc(struct balloon_dev_info *b_dev_info,
> - const struct address_space_operations *a_ops);
> -
> -static inline void balloon_mapping_free(struct address_space
> *balloon_mapping)
> -{
> - kfree(balloon_mapping);
> -}
> -
> -/*
> - * page_flags_cleared - helper to perform balloon @page ->flags tests.
> - *
> - * As balloon pages are obtained from buddy and we do not play with
> page->flags
> - * at driver level (exception made when we get the page lock for compaction),
> - * we can safely identify a ballooned page by checking if the
> - * PAGE_FLAGS_CHECK_AT_PREP page->flags are all cleared. This approach also
> - * helps us skip ballooned pages that are locked for compaction or release,
> thus
> - * mitigating their racy check at balloon_page_movable()
> - */
> -static inline bool page_flags_cleared(struct page *page)
> -{
> - return !(page->flags & PAGE_FLAGS_CHECK_AT_PREP);
> -}
> -
> -/*
> - * __is_movable_balloon_page - helper to perform @page mapping->flags tests
> - */
> -static inline bool __is_movable_balloon_page(struct page *page)
> -{
> - struct address_space *mapping = page->mapping;
> - return !PageAnon(page) && mapping_balloon(mapping);
> -}
> -
> -/*
> - * balloon_page_movable - test page->mapping->flags to identify balloon pages
> - * that can be moved by compaction/migration.
> - *
> - * This function is used at core compaction's page isolation scheme,
> therefore
> - * most pages exposed to it are not enlisted as balloon pages and so, to
> avoid
> - * undesired side effects like racing against __free_pages(), we cannot
> afford
> - * holding the page locked while testing page->mapping->flags here.
> - *
> - * As we might return false positives in the case of a balloon page being
> just
> - * released under us, the page->mapping->flags need to be re-tested later,
> - * under the proper page lock, at the functions that will be coping with the
> - * balloon page case.
> - */
> -static inline bool balloon_page_movable(struct page *page)
> -{
> - /*
> - * Before dereferencing and testing mapping->flags, let's make sure
> - * this is not a page that uses ->mapping in a different way
> - */
> - if (page_flags_cleared(page) && !page_mapped(page) &&
> - page_count(page) == 1)
> - return __is_movable_balloon_page(page);
> -
> - return false;
> -}
> -
> -/*
> - * isolated_balloon_page - identify an isolated balloon page on private
> - * compaction/migration page lists.
> - *
> - * After a compaction thread isolates a balloon page for migration, it raises
> - * the page refcount to prevent concurrent compaction threads from
> re-isolating
> - * the same page. For that reason putback_movable_pages(), or other routines
> - * that need to identify isolated balloon pages on
Re: [PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
On Sat, Aug 30, 2014 at 08:41:23PM +0400, Konstantin Khlebnikov wrote:
From: Konstantin Khlebnikov k.khlebni...@samsung.com
This patch replaces checking AS_BALLOON_MAP in page-mapping-flags
with PageBalloon which is stored directly in the struct page.
All code of balloon_compaction now under CONFIG_MEMORY_BALLOON.
Signed-off-by: Konstantin Khlebnikov k.khlebni...@samsung.com
---
drivers/virtio/Kconfig |1
include/linux/balloon_compaction.h | 135
++--
mm/Kconfig |2 -
mm/Makefile|3 +
mm/balloon_compaction.c|7 +-
mm/compaction.c|9 +-
mm/migrate.c |6 +-
mm/vmscan.c|2 -
8 files changed, 39 insertions(+), 126 deletions(-)
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index c6683f2..00b2286 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -25,6 +25,7 @@ config VIRTIO_PCI
config VIRTIO_BALLOON
tristate Virtio balloon driver
depends on VIRTIO
+ select MEMORY_BALLOON
---help---
This driver supports increasing and decreasing the amount
of memory within a KVM guest.
diff --git a/include/linux/balloon_compaction.h
b/include/linux/balloon_compaction.h
index 284fc1d..09f8c5a 100644
--- a/include/linux/balloon_compaction.h
+++ b/include/linux/balloon_compaction.h
@@ -46,6 +46,8 @@
#include linux/gfp.h
#include linux/err.h
+#ifdef CONFIG_MEMORY_BALLOON
+
/*
* Balloon device information descriptor.
* This struct is used to allow the common balloon compaction interface
@@ -93,91 +95,6 @@ static inline void balloon_page_free(struct page *page)
__free_page(page);
}
-#ifdef CONFIG_BALLOON_COMPACTION
-extern bool balloon_page_isolate(struct page *page);
-extern void balloon_page_putback(struct page *page);
-extern int balloon_page_migrate(struct page *newpage,
- struct page *page, enum migrate_mode mode);
-extern struct address_space
-*balloon_mapping_alloc(struct balloon_dev_info *b_dev_info,
- const struct address_space_operations *a_ops);
-
-static inline void balloon_mapping_free(struct address_space
*balloon_mapping)
-{
- kfree(balloon_mapping);
-}
-
-/*
- * page_flags_cleared - helper to perform balloon @page -flags tests.
- *
- * As balloon pages are obtained from buddy and we do not play with
page-flags
- * at driver level (exception made when we get the page lock for compaction),
- * we can safely identify a ballooned page by checking if the
- * PAGE_FLAGS_CHECK_AT_PREP page-flags are all cleared. This approach also
- * helps us skip ballooned pages that are locked for compaction or release,
thus
- * mitigating their racy check at balloon_page_movable()
- */
-static inline bool page_flags_cleared(struct page *page)
-{
- return !(page-flags PAGE_FLAGS_CHECK_AT_PREP);
-}
-
-/*
- * __is_movable_balloon_page - helper to perform @page mapping-flags tests
- */
-static inline bool __is_movable_balloon_page(struct page *page)
-{
- struct address_space *mapping = page-mapping;
- return !PageAnon(page) mapping_balloon(mapping);
-}
-
-/*
- * balloon_page_movable - test page-mapping-flags to identify balloon pages
- * that can be moved by compaction/migration.
- *
- * This function is used at core compaction's page isolation scheme,
therefore
- * most pages exposed to it are not enlisted as balloon pages and so, to
avoid
- * undesired side effects like racing against __free_pages(), we cannot
afford
- * holding the page locked while testing page-mapping-flags here.
- *
- * As we might return false positives in the case of a balloon page being
just
- * released under us, the page-mapping-flags need to be re-tested later,
- * under the proper page lock, at the functions that will be coping with the
- * balloon page case.
- */
-static inline bool balloon_page_movable(struct page *page)
-{
- /*
- * Before dereferencing and testing mapping-flags, let's make sure
- * this is not a page that uses -mapping in a different way
- */
- if (page_flags_cleared(page) !page_mapped(page)
- page_count(page) == 1)
- return __is_movable_balloon_page(page);
-
- return false;
-}
-
-/*
- * isolated_balloon_page - identify an isolated balloon page on private
- * compaction/migration page lists.
- *
- * After a compaction thread isolates a balloon page for migration, it raises
- * the page refcount to prevent concurrent compaction threads from
re-isolating
- * the same page. For that reason putback_movable_pages(), or other routines
- * that need to identify isolated balloon pages on private pagelists, cannot
- * rely on balloon_page_movable() to accomplish the task.
[PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
From: Konstantin Khlebnikov
This patch replaces checking AS_BALLOON_MAP in page->mapping->flags
with PageBalloon which is stored directly in the struct page.
All code of balloon_compaction now under CONFIG_MEMORY_BALLOON.
Signed-off-by: Konstantin Khlebnikov
---
drivers/virtio/Kconfig |1
include/linux/balloon_compaction.h | 135 ++--
mm/Kconfig |2 -
mm/Makefile|3 +
mm/balloon_compaction.c|7 +-
mm/compaction.c|9 +-
mm/migrate.c |6 +-
mm/vmscan.c|2 -
8 files changed, 39 insertions(+), 126 deletions(-)
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index c6683f2..00b2286 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -25,6 +25,7 @@ config VIRTIO_PCI
config VIRTIO_BALLOON
tristate "Virtio balloon driver"
depends on VIRTIO
+ select MEMORY_BALLOON
---help---
This driver supports increasing and decreasing the amount
of memory within a KVM guest.
diff --git a/include/linux/balloon_compaction.h
b/include/linux/balloon_compaction.h
index 284fc1d..09f8c5a 100644
--- a/include/linux/balloon_compaction.h
+++ b/include/linux/balloon_compaction.h
@@ -46,6 +46,8 @@
#include
#include
+#ifdef CONFIG_MEMORY_BALLOON
+
/*
* Balloon device information descriptor.
* This struct is used to allow the common balloon compaction interface
@@ -93,91 +95,6 @@ static inline void balloon_page_free(struct page *page)
__free_page(page);
}
-#ifdef CONFIG_BALLOON_COMPACTION
-extern bool balloon_page_isolate(struct page *page);
-extern void balloon_page_putback(struct page *page);
-extern int balloon_page_migrate(struct page *newpage,
- struct page *page, enum migrate_mode mode);
-extern struct address_space
-*balloon_mapping_alloc(struct balloon_dev_info *b_dev_info,
- const struct address_space_operations *a_ops);
-
-static inline void balloon_mapping_free(struct address_space *balloon_mapping)
-{
- kfree(balloon_mapping);
-}
-
-/*
- * page_flags_cleared - helper to perform balloon @page ->flags tests.
- *
- * As balloon pages are obtained from buddy and we do not play with page->flags
- * at driver level (exception made when we get the page lock for compaction),
- * we can safely identify a ballooned page by checking if the
- * PAGE_FLAGS_CHECK_AT_PREP page->flags are all cleared. This approach also
- * helps us skip ballooned pages that are locked for compaction or release,
thus
- * mitigating their racy check at balloon_page_movable()
- */
-static inline bool page_flags_cleared(struct page *page)
-{
- return !(page->flags & PAGE_FLAGS_CHECK_AT_PREP);
-}
-
-/*
- * __is_movable_balloon_page - helper to perform @page mapping->flags tests
- */
-static inline bool __is_movable_balloon_page(struct page *page)
-{
- struct address_space *mapping = page->mapping;
- return !PageAnon(page) && mapping_balloon(mapping);
-}
-
-/*
- * balloon_page_movable - test page->mapping->flags to identify balloon pages
- * that can be moved by compaction/migration.
- *
- * This function is used at core compaction's page isolation scheme, therefore
- * most pages exposed to it are not enlisted as balloon pages and so, to avoid
- * undesired side effects like racing against __free_pages(), we cannot afford
- * holding the page locked while testing page->mapping->flags here.
- *
- * As we might return false positives in the case of a balloon page being just
- * released under us, the page->mapping->flags need to be re-tested later,
- * under the proper page lock, at the functions that will be coping with the
- * balloon page case.
- */
-static inline bool balloon_page_movable(struct page *page)
-{
- /*
-* Before dereferencing and testing mapping->flags, let's make sure
-* this is not a page that uses ->mapping in a different way
-*/
- if (page_flags_cleared(page) && !page_mapped(page) &&
- page_count(page) == 1)
- return __is_movable_balloon_page(page);
-
- return false;
-}
-
-/*
- * isolated_balloon_page - identify an isolated balloon page on private
- *compaction/migration page lists.
- *
- * After a compaction thread isolates a balloon page for migration, it raises
- * the page refcount to prevent concurrent compaction threads from re-isolating
- * the same page. For that reason putback_movable_pages(), or other routines
- * that need to identify isolated balloon pages on private pagelists, cannot
- * rely on balloon_page_movable() to accomplish the task.
- */
-static inline bool isolated_balloon_page(struct page *page)
-{
- /* Already isolated balloon pages, by default, have a raised refcount */
- if (page_flags_cleared(page) && !page_mapped(page)
[PATCH v2 5/6] mm/balloon_compaction: use common page ballooning
From: Konstantin Khlebnikov k.khlebni...@samsung.com
This patch replaces checking AS_BALLOON_MAP in page-mapping-flags
with PageBalloon which is stored directly in the struct page.
All code of balloon_compaction now under CONFIG_MEMORY_BALLOON.
Signed-off-by: Konstantin Khlebnikov k.khlebni...@samsung.com
---
drivers/virtio/Kconfig |1
include/linux/balloon_compaction.h | 135 ++--
mm/Kconfig |2 -
mm/Makefile|3 +
mm/balloon_compaction.c|7 +-
mm/compaction.c|9 +-
mm/migrate.c |6 +-
mm/vmscan.c|2 -
8 files changed, 39 insertions(+), 126 deletions(-)
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index c6683f2..00b2286 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -25,6 +25,7 @@ config VIRTIO_PCI
config VIRTIO_BALLOON
tristate Virtio balloon driver
depends on VIRTIO
+ select MEMORY_BALLOON
---help---
This driver supports increasing and decreasing the amount
of memory within a KVM guest.
diff --git a/include/linux/balloon_compaction.h
b/include/linux/balloon_compaction.h
index 284fc1d..09f8c5a 100644
--- a/include/linux/balloon_compaction.h
+++ b/include/linux/balloon_compaction.h
@@ -46,6 +46,8 @@
#include linux/gfp.h
#include linux/err.h
+#ifdef CONFIG_MEMORY_BALLOON
+
/*
* Balloon device information descriptor.
* This struct is used to allow the common balloon compaction interface
@@ -93,91 +95,6 @@ static inline void balloon_page_free(struct page *page)
__free_page(page);
}
-#ifdef CONFIG_BALLOON_COMPACTION
-extern bool balloon_page_isolate(struct page *page);
-extern void balloon_page_putback(struct page *page);
-extern int balloon_page_migrate(struct page *newpage,
- struct page *page, enum migrate_mode mode);
-extern struct address_space
-*balloon_mapping_alloc(struct balloon_dev_info *b_dev_info,
- const struct address_space_operations *a_ops);
-
-static inline void balloon_mapping_free(struct address_space *balloon_mapping)
-{
- kfree(balloon_mapping);
-}
-
-/*
- * page_flags_cleared - helper to perform balloon @page -flags tests.
- *
- * As balloon pages are obtained from buddy and we do not play with page-flags
- * at driver level (exception made when we get the page lock for compaction),
- * we can safely identify a ballooned page by checking if the
- * PAGE_FLAGS_CHECK_AT_PREP page-flags are all cleared. This approach also
- * helps us skip ballooned pages that are locked for compaction or release,
thus
- * mitigating their racy check at balloon_page_movable()
- */
-static inline bool page_flags_cleared(struct page *page)
-{
- return !(page-flags PAGE_FLAGS_CHECK_AT_PREP);
-}
-
-/*
- * __is_movable_balloon_page - helper to perform @page mapping-flags tests
- */
-static inline bool __is_movable_balloon_page(struct page *page)
-{
- struct address_space *mapping = page-mapping;
- return !PageAnon(page) mapping_balloon(mapping);
-}
-
-/*
- * balloon_page_movable - test page-mapping-flags to identify balloon pages
- * that can be moved by compaction/migration.
- *
- * This function is used at core compaction's page isolation scheme, therefore
- * most pages exposed to it are not enlisted as balloon pages and so, to avoid
- * undesired side effects like racing against __free_pages(), we cannot afford
- * holding the page locked while testing page-mapping-flags here.
- *
- * As we might return false positives in the case of a balloon page being just
- * released under us, the page-mapping-flags need to be re-tested later,
- * under the proper page lock, at the functions that will be coping with the
- * balloon page case.
- */
-static inline bool balloon_page_movable(struct page *page)
-{
- /*
-* Before dereferencing and testing mapping-flags, let's make sure
-* this is not a page that uses -mapping in a different way
-*/
- if (page_flags_cleared(page) !page_mapped(page)
- page_count(page) == 1)
- return __is_movable_balloon_page(page);
-
- return false;
-}
-
-/*
- * isolated_balloon_page - identify an isolated balloon page on private
- *compaction/migration page lists.
- *
- * After a compaction thread isolates a balloon page for migration, it raises
- * the page refcount to prevent concurrent compaction threads from re-isolating
- * the same page. For that reason putback_movable_pages(), or other routines
- * that need to identify isolated balloon pages on private pagelists, cannot
- * rely on balloon_page_movable() to accomplish the task.
- */
-static inline bool isolated_balloon_page(struct page *page)
-{
- /* Already isolated balloon pages, by default, have a raised refcount */
- if
