Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1641418

[PATCH 09/14] mm: __first_valid_page skip over offline pages

Show all headers | View raw

From: Michal Hocko <mhocko@suse.com>

__first_valid_page skips over invalid pfns in the range but it might
still stumble over offline pages. At least start_isolate_page_range
will mark those set_migratetype_isolate. This doesn't represent
any immediate AFAICS because alloc_contig_range will fail to isolate
those pages but it relies on not fully initialized page which will
become a problem later when we stop associating offline pages to zones.
Use pfn_to_online_page to handle this.

This is more a preparatory patch than a fix.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 mm/page_isolation.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 5092e4ef00c8..3606104893e0 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -138,12 +138,18 @@ static inline struct page *
 __first_valid_page(unsigned long pfn, unsigned long nr_pages)
 {
 	int i;
-	for (i = 0; i < nr_pages; i++)
-		if (pfn_valid_within(pfn + i))
-			break;
-	if (unlikely(i == nr_pages))
-		return NULL;
-	return pfn_to_page(pfn + i);
+
+	for (i = 0; i < nr_pages; i++) {
+		struct page *page;
+
+		if (!pfn_valid_within(pfn + i))
+			continue;
+		page = pfn_to_online_page(pfn + i);
+		if (!page)
+			continue;
+		return page;
+	}
+	return NULL;
 }
 
 /*
@@ -184,8 +190,12 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 undo:
 	for (pfn = start_pfn;
 	     pfn < undo_pfn;
-	     pfn += pageblock_nr_pages)
-		unset_migratetype_isolate(pfn_to_page(pfn), migratetype);
+	     pfn += pageblock_nr_pages) {
+		struct page *page = pfn_to_online_page(pfn);
+		if (!page)
+			continue;
+		unset_migratetype_isolate(page, migratetype);
+	}
 
 	return -EBUSY;
 }
-- 
2.11.0

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH -v4 0/14] mm: make movable onlining suck less Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:00 +0200
  [PATCH 07/14] mm: consider zone which is not fully populated to have holes Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
    Re: [PATCH 07/14] mm: consider zone which is not fully populated to  have holes Vlastimil Babka <vbabka@suse.cz> - 2017-05-18 18:20 +0200
      Re: [PATCH 07/14] mm: consider zone which is not fully populated to  have holes Michal Hocko <mhocko@kernel.org> - 2017-05-18 18:50 +0200
        Re: [PATCH 07/14] mm: consider zone which is not fully populated to  have holes Vlastimil Babka <vbabka@suse.cz> - 2017-05-19 09:30 +0200
  [PATCH 09/14] mm: __first_valid_page skip over offline pages Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
    Re: [PATCH 09/14] mm: __first_valid_page skip over offline pages Vlastimil Babka <vbabka@suse.cz> - 2017-05-19 10:10 +0200
  [PATCH 14/14] mm, memory_hotplug: remove unused cruft after memory hotplug rework Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 04/14] mm, memory_hotplug: get rid of is_zone_device_section Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 12/14] mm, memory_hotplug: replace for_device by want_memblock in arch_add_memory Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 08/14] mm, compaction: skip over holes in __reset_isolation_suitable Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
    Re: [PATCH 08/14] mm, compaction: skip over holes in  __reset_isolation_suitable Vlastimil Babka <vbabka@suse.cz> - 2017-05-19 09:30 +0200
  [PATCH 10/14] mm, vmstat: skip reporting offline pages in pagetypeinfo Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
    Re: [PATCH 10/14] mm, vmstat: skip reporting offline pages in  pagetypeinfo Vlastimil Babka <vbabka@suse.cz> - 2017-05-19 10:20 +0200
  [PATCH 05/14] mm, memory_hotplug: split up register_one_node Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 11/14] mm, memory_hotplug: do not associate hotadded memory to zones until online Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
    Re: [PATCH 11/14] mm, memory_hotplug: do not associate hotadded  memory to zones until online Vlastimil Babka <vbabka@suse.cz> - 2017-05-19 11:00 +0200
  [PATCH 06/14] mm, memory_hotplug: consider offline memblocks removable Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 13/14] mm, memory_hotplug: fix the section mismatch warning Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200
  [PATCH 03/14] mm: drop page_initialized check from get_nid_for_pfn Michal Hocko <mhocko@kernel.org> - 2017-05-15 11:10 +0200

csiph-web