All of lore.kernel.org
 help / color / mirror / Atom feed
From: Oscar Salvador <osalvador@suse.de>
To: akpm@linux-foundation.org
Cc: mhocko@suse.com, linux-mm@kvack.org, mike.kravetz@oracle.com,
	david@redhat.com, aneesh.kumar@linux.vnet.ibm.com,
	naoya.horiguchi@nec.com, linux-kernel@vger.kernel.org,
	Oscar Salvador <osalvador@suse.de>,
	Oscar Salvador <osalvador@suse.com>
Subject: [PATCH v4 13/15] mm,hwpoison: Refactor soft_offline_huge_page and __soft_offline_page
Date: Thu, 16 Jul 2020 14:38:07 +0200	[thread overview]
Message-ID: <20200716123810.25292-14-osalvador@suse.de> (raw)
In-Reply-To: <20200716123810.25292-1-osalvador@suse.de>

Merging soft_offline_huge_page and __soft_offline_page let us get rid of
quite some duplicated code, and makes the code much easier to follow.

Now, __soft_offline_page will handle both normal and hugetlb pages.

Note that move put_page() block to the beginning of page_handle_poison()
with drain_all_pages() in order to make sure that the target page is
freed and sent into free list to make take_page_off_buddy() work properly.

Signed-off-by: Oscar Salvador <osalvador@suse.com>
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
---
 mm/memory-failure.c | 141 ++++++++++++++++----------------------------
 1 file changed, 52 insertions(+), 89 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index c0ebab4eed4c..c6c83337708a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1723,62 +1723,50 @@ static int get_any_page(struct page *page, unsigned long pfn)
 	return ret;
 }
 
-static int soft_offline_huge_page(struct page *page)
+static bool isolate_page(struct page *page, struct list_head *pagelist)
 {
-	int ret = -EBUSY;
-	unsigned long pfn = page_to_pfn(page);
-	struct page *hpage = compound_head(page);
-	LIST_HEAD(pagelist);
+	bool isolated = false;
+	bool lru = PageLRU(page);
 
-	/*
-	 * This double-check of PageHWPoison is to avoid the race with
-	 * memory_failure(). See also comment in __soft_offline_page().
-	 */
-	lock_page(hpage);
-	if (PageHWPoison(hpage)) {
-		unlock_page(hpage);
-		put_page(hpage);
-		pr_info("soft offline: %#lx hugepage already poisoned\n", pfn);
-		return -EBUSY;
+	if (PageHuge(page)) {
+		isolated = isolate_huge_page(page, pagelist);
+	} else {
+		if (lru)
+			isolated = !isolate_lru_page(page);
+		else
+			isolated = !isolate_movable_page(page, ISOLATE_UNEVICTABLE);
+
+		if (isolated)
+			list_add(&page->lru, pagelist);
 	}
-	unlock_page(hpage);
 
-	ret = isolate_huge_page(hpage, &pagelist);
+	if (isolated && lru)
+		inc_node_page_state(page, NR_ISOLATED_ANON +
+				    page_is_file_lru(page));
+
 	/*
-	 * get_any_page() and isolate_huge_page() takes a refcount each,
-	 * so need to drop one here.
+	 * If we succeed to isolate the page, we grabbed another refcount on
+	 * the page, so we can safely drop the one we got from get_any_pages().
+	 * If we failed to isolate the page, it means that we cannot go further
+	 * and we will return an error, so drop the reference we got from
+	 * get_any_pages() as well.
 	 */
-	put_page(hpage);
-	if (!ret) {
-		pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn);
-		return -EBUSY;
-	}
-
-	ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
-				MIGRATE_SYNC, MR_MEMORY_FAILURE);
-	if (ret) {
-		pr_info("soft offline: %#lx: hugepage migration failed %d, type %lx (%pGp)\n",
-			pfn, ret, page->flags, &page->flags);
-		if (!list_empty(&pagelist))
-			putback_movable_pages(&pagelist);
-		if (ret > 0)
-			ret = -EIO;
-	} else {
-		/*
-		 * At this point the page cannot be in-use since we do not
-		 * let the page to go back to hugetlb freelists.
-		 * In that case we just need to dissolve it.
-		 * page_handle_poison will take care of it.
-		 */
-		page_handle_poison(page, true, true, true);
-	}
-	return ret;
+	put_page(page);
+	return isolated;
 }
 
+/*
+ * __soft_offline_page handles hugetlb-pages and non-hugetlb pages.
+ * If the page is a non-dirty unmapped page-cache page, it simply invalidates.
+ */
 static int __soft_offline_page(struct page *page)
 {
-	int ret;
+	int ret = 0;
 	unsigned long pfn = page_to_pfn(page);
+	struct page *hpage = compound_head(page);
+	const char *msg_page[] = {"page", "hugepage"};
+	bool huge = PageHuge(page);
+	LIST_HEAD(pagelist);
 
 	/*
 	 * Check PageHWPoison again inside page lock because PageHWPoison
@@ -1787,88 +1775,63 @@ static int __soft_offline_page(struct page *page)
 	 * so there's no race between soft_offline_page() and memory_failure().
 	 */
 	lock_page(page);
-	wait_on_page_writeback(page);
+	if (!PageHuge(page))
+		wait_on_page_writeback(page);
 	if (PageHWPoison(page)) {
 		unlock_page(page);
 		put_page(page);
 		pr_info("soft offline: %#lx page already poisoned\n", pfn);
 		return -EBUSY;
 	}
-	/*
-	 * Try to invalidate first. This should work for
-	 * non dirty unmapped page cache pages.
-	 */
-	ret = invalidate_inode_page(page);
+
+	if (!PageHuge(page))
+		/*
+		 * Try to invalidate first. This should work for
+		 * non dirty unmapped page cache pages.
+		 */
+		ret = invalidate_inode_page(page);
 	unlock_page(page);
+
 	/*
 	 * RED-PEN would be better to keep it isolated here, but we
 	 * would need to fix isolation locking first.
 	 */
 	if (ret == 1) {
 		pr_info("soft_offline: %#lx: invalidated\n", pfn);
-		page_handle_poison(page, true, true, false);
+		page_handle_poison(page, false, true, false);
 		return 0;
 	}
 
-	/*
-	 * Simple invalidation didn't work.
-	 * Try to migrate to a new page instead. migrate.c
-	 * handles a large number of cases for us.
-	 */
-	if (PageLRU(page))
-		ret = isolate_lru_page(page);
-	else
-		ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
-	/*
-	 * Drop page reference which is came from get_any_page()
-	 * successful isolate_lru_page() already took another one.
-	 */
-	put_page(page);
-	if (!ret) {
-		LIST_HEAD(pagelist);
-		/*
-		 * After isolated lru page, the PageLRU will be cleared,
-		 * so use !__PageMovable instead for LRU page's mapping
-		 * cannot have PAGE_MAPPING_MOVABLE.
-		 */
-		if (!__PageMovable(page))
-			inc_node_page_state(page, NR_ISOLATED_ANON +
-						page_is_file_lru(page));
-		list_add(&page->lru, &pagelist);
-		ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
+	if (isolate_page(hpage, &pagelist)) {
+	ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
 					MIGRATE_SYNC, MR_MEMORY_FAILURE);
 		if (!ret) {
-			page_handle_poison(page, true, true, false);
+			page_handle_poison(page, true, true, huge);
 		} else {
 			if (!list_empty(&pagelist))
 				putback_movable_pages(&pagelist);
 
-			pr_info("soft offline: %#lx: migration failed %d, type %lx (%pGp)\n",
-				pfn, ret, page->flags, &page->flags);
+			pr_info("soft offline: %#lx: %s migration failed %d, type %lx (%pGp)\n",
+				 pfn, msg_page[huge], ret, page->flags, &page->flags);
 			if (ret > 0)
 				ret = -EIO;
 		}
 	} else {
-		pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx (%pGp)\n",
-			pfn, ret, page_count(page), page->flags, &page->flags);
+		pr_info("soft offline: %#lx: %s isolation failed: %d, page count %d, type %lx (%pGp)\n",
+			 pfn, msg_page[huge], ret, page_count(page), page->flags, &page->flags);
 	}
 	return ret;
 }
 
 static int soft_offline_in_use_page(struct page *page)
 {
-	int ret;
 	struct page *hpage = compound_head(page);
 
 	if (!PageHuge(page) && PageTransHuge(hpage))
 		if (try_to_split_thp_page(page, "soft offline") < 0)
 			return -EBUSY;
 
-	if (PageHuge(page))
-		ret = soft_offline_huge_page(page);
-	else
-		ret = __soft_offline_page(page);
-	return ret;
+	return __soft_offline_page(page);
 }
 
 static int soft_offline_free_page(struct page *page)
-- 
2.26.2


  parent reply	other threads:[~2020-07-16 12:38 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-16 12:37 [PATCH v4 00/15] Hwpoison soft-offline rework Oscar Salvador
2020-07-16 12:37 ` [PATCH v4 01/15] mm,hwpoison: cleanup unused PageHuge() check Oscar Salvador
2020-07-16 12:37 ` [PATCH v4 02/15] mm, hwpoison: remove recalculating hpage Oscar Salvador
2020-07-16 12:37 ` [PATCH v4 03/15] mm,madvise: call soft_offline_page() without MF_COUNT_INCREASED Oscar Salvador
2020-07-16 23:15   ` Mike Kravetz
2020-07-16 12:37 ` [PATCH v4 04/15] mm,madvise: Refactor madvise_inject_error Oscar Salvador
2020-07-16 12:37 ` [PATCH v4 05/15] mm,hwpoison-inject: don't pin for hwpoison_filter Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 06/15] mm,hwpoison: Un-export get_hwpoison_page and make it static Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 07/15] mm,hwpoison: Kill put_hwpoison_page Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 08/15] mm,hwpoison: remove MF_COUNT_INCREASED Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 09/15] mm,hwpoison: remove flag argument from soft offline functions Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 10/15] mm,hwpoison: Unify THP handling for hard and soft offline Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 11/15] mm,hwpoison: Rework soft offline for free pages Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 12/15] mm,hwpoison: Rework soft offline for in-use pages Oscar Salvador
2020-07-17  6:55   ` HORIGUCHI NAOYA(堀口 直也)
     [not found]   ` <f7387d64d0024d15a1bc821a8e19b8f0@DB7PR04MB5180.eurprd04.prod.outlook.com>
2020-07-20  8:27     ` osalvador
2020-07-22  8:08       ` osalvador
2020-07-23 10:19         ` Oscar Salvador
2020-07-16 12:38 ` Oscar Salvador [this message]
2020-07-16 12:38 ` [PATCH v4 14/15] mm,hwpoison: Return 0 if the page is already poisoned in soft-offline Oscar Salvador
2020-07-16 12:38 ` [PATCH v4 15/15] mm,hwpoison: introduce MF_MSG_UNSPLIT_THP Oscar Salvador
2020-07-16 12:38 ` [PATCH] x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support Oscar Salvador
2020-07-16 12:43   ` osalvador
2020-07-17 14:49 ` [PATCH v4 00/15] Hwpoison soft-offline rework Qian Cai

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200716123810.25292-14-osalvador@suse.de \
    --to=osalvador@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=aneesh.kumar@linux.vnet.ibm.com \
    --cc=david@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.com \
    --cc=mike.kravetz@oracle.com \
    --cc=naoya.horiguchi@nec.com \
    --cc=osalvador@suse.com \
    --subject='Re: [PATCH v4 13/15] mm,hwpoison: Refactor soft_offline_huge_page and __soft_offline_page' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.