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[183.57.50.164]) by mx.google.com with SMTP id u84si12613457pgb.258.2017.01.31.15.35.20 for ; Tue, 31 Jan 2017 15:35:21 -0800 (PST) From: ysxie@foxmail.com Subject: [PATCH v5 4/4] mm/hotplug: enable memory hotplug for non-lru movable pages Date: Wed, 1 Feb 2017 07:28:43 +0800 Message-Id: <1485905323-2615-1-git-send-email-ysxie@foxmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: n-horiguchi@ah.jp.nec.com, mhocko@suse.com, akpm@linux-foundation.org, minchan@kernel.org, vbabka@suse.cz, mgorman@techsingularity.net, hannes@cmpxchg.org, iamjoonsoo.kim@lge.com, izumi.taku@jp.fujitsu.com, arbab@linux.vnet.ibm.com, vkuznets@redhat.com, ak@linux.intel.com, guohanjun@huawei.com, qiuxishi@huawei.com From: Yisheng Xie We had considered all of the non-lru pages as unmovable before commit bda807d44454 ("mm: migrate: support non-lru movable page migration"). But now some of non-lru pages like zsmalloc, virtio-balloon pages also become movable. So we can offline such blocks by using non-lru page migration. This patch straightforwardly add non-lru migration code, which means adding non-lru related code to the functions which scan over pfn and collect pages to be migrated and isolate them before migration. Signed-off-by: Yisheng Xie Cc: Michal Hocko Cc: Minchan Kim Cc: Naoya Horiguchi CC: Vlastimil Babka --- mm/memory_hotplug.c | 28 +++++++++++++++++----------- mm/page_alloc.c | 8 ++++++-- 2 files changed, 23 insertions(+), 13 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index ca2723d..ea1be08 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1516,10 +1516,10 @@ int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) } /* - * Scan pfn range [start,end) to find movable/migratable pages (LRU pages - * and hugepages). We scan pfn because it's much easier than scanning over - * linked list. This function returns the pfn of the first found movable - * page if it's found, otherwise 0. + * Scan pfn range [start,end) to find movable/migratable pages (LRU pages, + * non-lru movable pages and hugepages). We scan pfn because it's much + * easier than scanning over linked list. This function returns the pfn + * of the first found movable page if it's found, otherwise 0. */ static unsigned long scan_movable_pages(unsigned long start, unsigned long end) { @@ -1530,6 +1530,8 @@ static unsigned long scan_movable_pages(unsigned long start, unsigned long end) page = pfn_to_page(pfn); if (PageLRU(page)) return pfn; + if (__PageMovable(page)) + return pfn; if (PageHuge(page)) { if (page_huge_active(page)) return pfn; @@ -1606,21 +1608,25 @@ static struct page *new_node_page(struct page *page, unsigned long private, if (!get_page_unless_zero(page)) continue; /* - * We can skip free pages. And we can only deal with pages on - * LRU. + * We can skip free pages. And we can deal with pages on + * LRU and non-lru movable pages. */ - ret = isolate_lru_page(page); + if (PageLRU(page)) + ret = isolate_lru_page(page); + else + ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE); if (!ret) { /* Success */ put_page(page); list_add_tail(&page->lru, &source); move_pages--; - inc_node_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); + if (!__PageMovable(page)) + inc_node_page_state(page, NR_ISOLATED_ANON + + page_is_file_cache(page)); } else { #ifdef CONFIG_DEBUG_VM - pr_alert("removing pfn %lx from LRU failed\n", pfn); - dump_page(page, "failed to remove from LRU"); + pr_alert("failed to isolate pfn %lx\n", pfn); + dump_page(page, "isolation failed"); #endif put_page(page); /* Because we don't have big zone->lock. we should diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f3e0c69..9c4e229 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7081,8 +7081,9 @@ void *__init alloc_large_system_hash(const char *tablename, * If @count is not zero, it is okay to include less @count unmovable pages * * PageLRU check without isolation or lru_lock could race so that - * MIGRATE_MOVABLE block might include unmovable pages. It means you can't - * expect this function should be exact. + * MIGRATE_MOVABLE block might include unmovable pages. And __PageMovable + * check without lock_page also may miss some movable non-lru pages at + * race condition. So you can't expect this function should be exact. */ bool has_unmovable_pages(struct zone *zone, struct page *page, int count, bool skip_hwpoisoned_pages) @@ -7138,6 +7139,9 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count, if (skip_hwpoisoned_pages && PageHWPoison(page)) continue; + if (__PageMovable(page)) + continue; + if (!PageLRU(page)) found++; /* -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org