Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755898AbbFBH16 (ORCPT ); Tue, 2 Jun 2015 03:27:58 -0400 Received: from lgeamrelo04.lge.com ([156.147.1.127]:53793 "EHLO lgeamrelo04.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755280AbbFBH1W (ORCPT ); Tue, 2 Jun 2015 03:27:22 -0400 X-Original-SENDERIP: 165.186.175.39 X-Original-MAILFROM: gioh.kim@lge.com From: Gioh Kim To: jlayton@poochiereds.net, bfields@fieldses.org, akpm@linux-foundation.org, vbabka@suse.cz, iamjoonsoo.kim@lge.com, mst@redhat.com, kirill@shutemov.name, minchan@kernel.org, mgorman@suse.de Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, virtualization@lists.linux-foundation.org, gunho.lee@lge.com, Gioh Kim Subject: [RFC 2/4] mm/balloon: apply driver page migratable into balloon driver Date: Tue, 2 Jun 2015 16:27:42 +0900 Message-Id: <1433230065-3573-3-git-send-email-gioh.kim@lge.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1433230065-3573-1-git-send-email-gioh.kim@lge.com> References: <1433230065-3573-1-git-send-email-gioh.kim@lge.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10264 Lines: 314 Apply driver page migration into balloon driver. Signed-off-by: Gioh Kim --- drivers/virtio/virtio_balloon.c | 2 ++ fs/proc/page.c | 4 +-- include/linux/balloon_compaction.h | 42 ++++++++++++++++------- include/linux/mm.h | 19 ----------- include/uapi/linux/kernel-page-flags.h | 2 +- mm/balloon_compaction.c | 61 ++++++++++++++++++++++++++++++++-- 6 files changed, 94 insertions(+), 36 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 6a356e3..cdd0038 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -496,6 +496,8 @@ static int virtballoon_probe(struct virtio_device *vdev) balloon_devinfo_init(&vb->vb_dev_info); #ifdef CONFIG_BALLOON_COMPACTION vb->vb_dev_info.migratepage = virtballoon_migratepage; + vb->vb_dev_info.mapping = balloon_mapping_alloc(&vb->vb_dev_info, + &balloon_aops); #endif err = init_vqs(vb); diff --git a/fs/proc/page.c b/fs/proc/page.c index 7eee2d8..e741307 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -143,8 +143,8 @@ u64 stable_page_flags(struct page *page) if (PageBuddy(page)) u |= 1 << KPF_BUDDY; - if (PageBalloon(page)) - u |= 1 << KPF_BALLOON; + if (PageMigratable(page)) + u |= 1 << KPF_MIGRATABLE; u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked); diff --git a/include/linux/balloon_compaction.h b/include/linux/balloon_compaction.h index 9b0a15d..0989e96 100644 --- a/include/linux/balloon_compaction.h +++ b/include/linux/balloon_compaction.h @@ -48,6 +48,7 @@ #include #include #include +#include /* * Balloon device information descriptor. @@ -62,6 +63,7 @@ struct balloon_dev_info { struct list_head pages; /* Pages enqueued & handled to Host */ int (*migratepage)(struct balloon_dev_info *, struct page *newpage, struct page *page, enum migrate_mode mode); + struct address_space *mapping; }; extern struct page *balloon_page_enqueue(struct balloon_dev_info *b_dev_info); @@ -73,24 +75,37 @@ static inline void balloon_devinfo_init(struct balloon_dev_info *balloon) spin_lock_init(&balloon->pages_lock); INIT_LIST_HEAD(&balloon->pages); balloon->migratepage = NULL; + balloon->mapping = NULL; } #ifdef CONFIG_BALLOON_COMPACTION -extern bool balloon_page_isolate(struct page *page); +extern const struct address_space_operations balloon_aops; +extern bool balloon_page_isolate(struct page *page, + isolate_mode_t mode); extern void balloon_page_putback(struct page *page); -extern int balloon_page_migrate(struct page *newpage, +extern int balloon_page_migrate(struct address_space *mapping, + 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); +} + /* - * __is_movable_balloon_page - helper to perform @page PageBalloon tests + * __is_movable_balloon_page - helper to perform @page PageMigratable tests */ static inline bool __is_movable_balloon_page(struct page *page) { - return PageBalloon(page); + return PageMigratable(page); } /* - * balloon_page_movable - test PageBalloon to identify balloon pages + * balloon_page_movable - test PageMigratable to identify balloon pages * and PagePrivate to check that the page is not * isolated and can be moved by compaction/migration. * @@ -99,7 +114,7 @@ static inline bool __is_movable_balloon_page(struct page *page) */ static inline bool balloon_page_movable(struct page *page) { - return PageBalloon(page) && PagePrivate(page); + return PageMigratable(page) && PagePrivate(page); } /* @@ -108,7 +123,7 @@ static inline bool balloon_page_movable(struct page *page) */ static inline bool isolated_balloon_page(struct page *page) { - return PageBalloon(page); + return PageMigratable(page); } /* @@ -123,7 +138,8 @@ static inline bool isolated_balloon_page(struct page *page) static inline void balloon_page_insert(struct balloon_dev_info *balloon, struct page *page) { - __SetPageBalloon(page); + page->mapping = balloon->mapping; + __SetPageMigratable(page); SetPagePrivate(page); set_page_private(page, (unsigned long)balloon); list_add(&page->lru, &balloon->pages); @@ -139,7 +155,8 @@ static inline void balloon_page_insert(struct balloon_dev_info *balloon, */ static inline void balloon_page_delete(struct page *page) { - __ClearPageBalloon(page); + page->mapping = NULL; + __ClearPageMigratable(page); set_page_private(page, 0); if (PagePrivate(page)) { ClearPagePrivate(page); @@ -166,13 +183,13 @@ static inline gfp_t balloon_mapping_gfp_mask(void) static inline void balloon_page_insert(struct balloon_dev_info *balloon, struct page *page) { - __SetPageBalloon(page); + __SetPageMigratable(page); list_add(&page->lru, &balloon->pages); } static inline void balloon_page_delete(struct page *page) { - __ClearPageBalloon(page); + __ClearPageMigratable(page); list_del(&page->lru); } @@ -191,7 +208,8 @@ static inline bool isolated_balloon_page(struct page *page) return false; } -static inline bool balloon_page_isolate(struct page *page) +static inline bool balloon_page_isolate(struct page *page, + isolate_mode_t mode) { return false; } diff --git a/include/linux/mm.h b/include/linux/mm.h index 422c484..2d991a0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -599,25 +599,6 @@ static inline void __ClearPageBuddy(struct page *page) atomic_set(&page->_mapcount, -1); } -#define PAGE_BALLOON_MAPCOUNT_VALUE (-256) - -static inline int PageBalloon(struct page *page) -{ - return atomic_read(&page->_mapcount) == PAGE_BALLOON_MAPCOUNT_VALUE; -} - -static inline void __SetPageBalloon(struct page *page) -{ - VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); - atomic_set(&page->_mapcount, PAGE_BALLOON_MAPCOUNT_VALUE); -} - -static inline void __ClearPageBalloon(struct page *page) -{ - VM_BUG_ON_PAGE(!PageBalloon(page), page); - atomic_set(&page->_mapcount, -1); -} - #define PAGE_MIGRATABLE_MAPCOUNT_VALUE (-256) static inline int PageMigratable(struct page *page) diff --git a/include/uapi/linux/kernel-page-flags.h b/include/uapi/linux/kernel-page-flags.h index a6c4962..a6a3c4b 100644 --- a/include/uapi/linux/kernel-page-flags.h +++ b/include/uapi/linux/kernel-page-flags.h @@ -31,7 +31,7 @@ #define KPF_KSM 21 #define KPF_THP 22 -#define KPF_BALLOON 23 +#define KPF_MIGRATABLE 23 #define KPF_ZERO_PAGE 24 diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index fcad832..f98a500 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -131,7 +131,7 @@ static inline void __putback_balloon_page(struct page *page) } /* __isolate_lru_page() counterpart for a ballooned page */ -bool balloon_page_isolate(struct page *page) +bool balloon_page_isolate(struct page *page, isolate_mode_t mode) { /* * Avoid burning cycles with pages that are yet under __free_pages(), @@ -175,6 +175,9 @@ bool balloon_page_isolate(struct page *page) /* putback_lru_page() counterpart for a ballooned page */ void balloon_page_putback(struct page *page) { + if (!isolated_balloon_page(page)) + return; + /* * 'lock_page()' stabilizes the page and prevents races against * concurrent isolation threads attempting to re-isolate it. @@ -193,12 +196,16 @@ void balloon_page_putback(struct page *page) } /* move_to_new_page() counterpart for a ballooned page */ -int balloon_page_migrate(struct page *newpage, +int balloon_page_migrate(struct address_space *mapping, + struct page *newpage, struct page *page, enum migrate_mode mode) { struct balloon_dev_info *balloon = balloon_page_device(page); int rc = -EAGAIN; + if (!isolated_balloon_page(page)) + return rc; + /* * Block others from accessing the 'newpage' when we get around to * establishing additional references. We should be the only one @@ -218,4 +225,54 @@ int balloon_page_migrate(struct page *newpage, unlock_page(newpage); return rc; } + +/* define the balloon_mapping->a_ops callback to allow balloon page migration */ +const struct address_space_operations balloon_aops = { + .migratepage = balloon_page_migrate, + .isolatepage = balloon_page_isolate, + .putbackpage = balloon_page_putback, +}; +EXPORT_SYMBOL_GPL(balloon_aops); + +struct address_space *balloon_mapping_alloc(struct balloon_dev_info *b_dev_info, + const struct address_space_operations *a_ops) +{ + struct address_space *mapping; + + mapping = kmalloc(sizeof(*mapping), GFP_KERNEL); + if (!mapping) + return ERR_PTR(-ENOMEM); + + /* + * Give a clean 'zeroed' status to all elements of this special + * balloon page->mapping struct address_space instance. + */ + address_space_init_once(mapping); + + /* + * Set mapping->flags appropriately, to allow balloon pages + * ->mapping identification. + */ + mapping_set_migratable(mapping); + mapping_set_gfp_mask(mapping, balloon_mapping_gfp_mask()); + + /* balloon's page->mapping->a_ops callback descriptor */ + mapping->a_ops = a_ops; + + /* + * Establish a pointer reference back to the balloon device descriptor + * this particular page->mapping will be servicing. + * This is used by compaction / migration procedures to identify and + * access the balloon device pageset while isolating / migrating pages. + * + * As some balloon drivers can register multiple balloon devices + * for a single guest, this also helps compaction / migration to + * properly deal with multiple balloon pagesets, when required. + */ + mapping->private_data = b_dev_info; + b_dev_info->mapping = mapping; + + return mapping; +} +EXPORT_SYMBOL_GPL(balloon_mapping_alloc); #endif /* CONFIG_BALLOON_COMPACTION */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/