From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx130.postini.com [74.125.245.130]) by kanga.kvack.org (Postfix) with SMTP id ED0396B0031 for ; Thu, 25 Jul 2013 02:09:14 -0400 (EDT) Received: by mail-oa0-f52.google.com with SMTP id g12so3292168oah.39 for ; Wed, 24 Jul 2013 23:09:14 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1374728103-17468-3-git-send-email-n-horiguchi@ah.jp.nec.com> References: <1374728103-17468-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1374728103-17468-3-git-send-email-n-horiguchi@ah.jp.nec.com> Date: Thu, 25 Jul 2013 14:09:13 +0800 Message-ID: Subject: Re: [PATCH 2/8] soft-offline: use migrate_pages() instead of migrate_huge_page() From: Hillf Danton Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: Andrew Morton , linux-mm@kvack.org, Mel Gorman , Hugh Dickins , KOSAKI Motohiro , Andi Kleen , Michal Hocko , Rik van Riel , "Aneesh Kumar K.V" , Wanpeng Li , linux-kernel@vger.kernel.org, Naoya Horiguchi On Thu, Jul 25, 2013 at 12:54 PM, Naoya Horiguchi wrote: > Currently migrate_huge_page() takes a pointer to a hugepage to be > migrated as an argument, instead of taking a pointer to the list of > hugepages to be migrated. This behavior was introduced in commit > 189ebff28 ("hugetlb: simplify migrate_huge_page()"), and was OK > because until now hugepage migration is enabled only for soft-offlining > which migrates only one hugepage in a single call. > > But the situation will change in the later patches in this series > which enable other users of page migration to support hugepage migration. > They can kick migration for both of normal pages and hugepages > in a single call, so we need to go back to original implementation > which uses linked lists to collect the hugepages to be migrated. > > With this patch, soft_offline_huge_page() switches to use migrate_pages(), > and migrate_huge_page() is not used any more. So let's remove it. > > ChangeLog v3: > - Merged with another cleanup patch (4/10 in previous version) > > Signed-off-by: Naoya Horiguchi > Acked-by: Andi Kleen > Reviewed-by: Wanpeng Li > --- Acked-by: Hillf Danton > include/linux/migrate.h | 5 ----- > mm/memory-failure.c | 15 ++++++++++++--- > mm/migrate.c | 28 ++-------------------------- > 3 files changed, 14 insertions(+), 34 deletions(-) > > diff --git v3.11-rc1.orig/include/linux/migrate.h v3.11-rc1/include/linux/migrate.h > index a405d3dc..6fe5214 100644 > --- v3.11-rc1.orig/include/linux/migrate.h > +++ v3.11-rc1/include/linux/migrate.h > @@ -41,8 +41,6 @@ extern int migrate_page(struct address_space *, > struct page *, struct page *, enum migrate_mode); > extern int migrate_pages(struct list_head *l, new_page_t x, > unsigned long private, enum migrate_mode mode, int reason); > -extern int migrate_huge_page(struct page *, new_page_t x, > - unsigned long private, enum migrate_mode mode); > > extern int fail_migrate_page(struct address_space *, > struct page *, struct page *); > @@ -62,9 +60,6 @@ static inline void putback_movable_pages(struct list_head *l) {} > static inline int migrate_pages(struct list_head *l, new_page_t x, > unsigned long private, enum migrate_mode mode, int reason) > { return -ENOSYS; } > -static inline int migrate_huge_page(struct page *page, new_page_t x, > - unsigned long private, enum migrate_mode mode) > - { return -ENOSYS; } > > static inline int migrate_prep(void) { return -ENOSYS; } > static inline int migrate_prep_local(void) { return -ENOSYS; } > diff --git v3.11-rc1.orig/mm/memory-failure.c v3.11-rc1/mm/memory-failure.c > index 2c13aa7..af6f61c 100644 > --- v3.11-rc1.orig/mm/memory-failure.c > +++ v3.11-rc1/mm/memory-failure.c > @@ -1467,6 +1467,7 @@ static int soft_offline_huge_page(struct page *page, int flags) > int ret; > unsigned long pfn = page_to_pfn(page); > struct page *hpage = compound_head(page); > + LIST_HEAD(pagelist); > > /* > * This double-check of PageHWPoison is to avoid the race with > @@ -1482,12 +1483,20 @@ static int soft_offline_huge_page(struct page *page, int flags) > unlock_page(hpage); > > /* Keep page count to indicate a given hugepage is isolated. */ > - ret = migrate_huge_page(hpage, new_page, MPOL_MF_MOVE_ALL, > - MIGRATE_SYNC); > - put_page(hpage); > + list_move(&hpage->lru, &pagelist); > + ret = migrate_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL, > + MIGRATE_SYNC, MR_MEMORY_FAILURE); > if (ret) { > pr_info("soft offline: %#lx: migration failed %d, type %lx\n", > pfn, ret, page->flags); > + /* > + * We know that soft_offline_huge_page() tries to migrate > + * only one hugepage pointed to by hpage, so we need not > + * run through the pagelist here. > + */ > + putback_active_hugepage(hpage); > + if (ret > 0) > + ret = -EIO; > } else { > set_page_hwpoison_huge_page(hpage); > dequeue_hwpoisoned_huge_page(hpage); > diff --git v3.11-rc1.orig/mm/migrate.c v3.11-rc1/mm/migrate.c > index b44a067..3ec47d3 100644 > --- v3.11-rc1.orig/mm/migrate.c > +++ v3.11-rc1/mm/migrate.c > @@ -979,6 +979,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, > > unlock_page(hpage); > out: > + if (rc != -EAGAIN) > + putback_active_hugepage(hpage); > put_page(new_hpage); > if (result) { > if (rc) > @@ -1066,32 +1068,6 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, > return rc; > } > > -int migrate_huge_page(struct page *hpage, new_page_t get_new_page, > - unsigned long private, enum migrate_mode mode) > -{ > - int pass, rc; > - > - for (pass = 0; pass < 10; pass++) { > - rc = unmap_and_move_huge_page(get_new_page, private, > - hpage, pass > 2, mode); > - switch (rc) { > - case -ENOMEM: > - goto out; > - case -EAGAIN: > - /* try again */ > - cond_resched(); > - break; > - case MIGRATEPAGE_SUCCESS: > - goto out; > - default: > - rc = -EIO; > - goto out; > - } > - } > -out: > - return rc; > -} > - > #ifdef CONFIG_NUMA > /* > * Move a list of individual pages > -- > 1.8.3.1 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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