Re: [PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

On 13.04.2018 15:32, David Hildenbrand wrote:
> If any page is still online, the section should stay online.
> 
> Signed-off-by: David Hildenbrand 
> ---

This is a duplicate, please ignore.

(get_maintainers.sh and my mail server had a little clinch, so I had to
send half of the series out manually -_- )

-- 

Thanks,

David / dhildenb

Re: [PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

On 13.04.2018 15:32, David Hildenbrand wrote:
> If any page is still online, the section should stay online.
> 
> Signed-off-by: David Hildenbrand 
> ---

This is a duplicate, please ignore.

(get_maintainers.sh and my mail server had a little clinch, so I had to
send half of the series out manually -_- )

-- 

Thanks,

David / dhildenb

[PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

If any page is still online, the section should stay online.

Signed-off-by: David Hildenbrand 
---
 mm/page_alloc.c |  2 +-
 mm/sparse.c | 25 -
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2e5dcfdb0908..ae9023da2ca2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8013,7 +8013,6 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
break;
if (pfn == end_pfn)
return;
-   offline_mem_sections(pfn, end_pfn);
zone = page_zone(pfn_to_page(pfn));
spin_lock_irqsave(>lock, flags);
pfn = start_pfn;
@@ -8051,6 +8050,7 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
pfn += (1 << order);
}
spin_unlock_irqrestore(>lock, flags);
+   offline_mem_sections(start_pfn, end_pfn);
 }
 #endif
 
diff --git a/mm/sparse.c b/mm/sparse.c
index 58cab483e81b..44978cb18fed 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -623,7 +623,27 @@ void online_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-/* Mark all memory sections within the pfn range as online */
+static bool all_pages_in_section_offline(unsigned long section_nr)
+{
+   unsigned long pfn = section_nr_to_pfn(section_nr);
+   struct page *page;
+   int i;
+
+   for (i = 0; i < PAGES_PER_SECTION; i++, pfn++) {
+   if (!pfn_valid(pfn))
+   continue;
+
+   page = pfn_to_page(pfn);
+   if (!PageOffline(page))
+   return false;
+   }
+   return true;
+}
+
+/*
+ * Mark all memory sections within the pfn range as offline (if all pages
+ * of a memory section are already offline)
+ */
 void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
 {
unsigned long pfn;
@@ -639,6 +659,9 @@ void offline_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
if (WARN_ON(!valid_section_nr(section_nr)))
continue;
 
+   if (!all_pages_in_section_offline(section_nr))
+   continue;
+
ms = __nr_to_section(section_nr);
ms->section_mem_map &= ~SECTION_IS_ONLINE;
}
-- 
2.14.3

[PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

If any page is still online, the section should stay online.

Signed-off-by: David Hildenbrand 
---
 mm/page_alloc.c |  2 +-
 mm/sparse.c | 25 -
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2e5dcfdb0908..ae9023da2ca2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8013,7 +8013,6 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
break;
if (pfn == end_pfn)
return;
-   offline_mem_sections(pfn, end_pfn);
zone = page_zone(pfn_to_page(pfn));
spin_lock_irqsave(>lock, flags);
pfn = start_pfn;
@@ -8051,6 +8050,7 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
pfn += (1 << order);
}
spin_unlock_irqrestore(>lock, flags);
+   offline_mem_sections(start_pfn, end_pfn);
 }
 #endif
 
diff --git a/mm/sparse.c b/mm/sparse.c
index 58cab483e81b..44978cb18fed 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -623,7 +623,27 @@ void online_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-/* Mark all memory sections within the pfn range as online */
+static bool all_pages_in_section_offline(unsigned long section_nr)
+{
+   unsigned long pfn = section_nr_to_pfn(section_nr);
+   struct page *page;
+   int i;
+
+   for (i = 0; i < PAGES_PER_SECTION; i++, pfn++) {
+   if (!pfn_valid(pfn))
+   continue;
+
+   page = pfn_to_page(pfn);
+   if (!PageOffline(page))
+   return false;
+   }
+   return true;
+}
+
+/*
+ * Mark all memory sections within the pfn range as offline (if all pages
+ * of a memory section are already offline)
+ */
 void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
 {
unsigned long pfn;
@@ -639,6 +659,9 @@ void offline_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
if (WARN_ON(!valid_section_nr(section_nr)))
continue;
 
+   if (!all_pages_in_section_offline(section_nr))
+   continue;
+
ms = __nr_to_section(section_nr);
ms->section_mem_map &= ~SECTION_IS_ONLINE;
}
-- 
2.14.3

[PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

If any page is still online, the section should stay online.

Signed-off-by: David Hildenbrand 
---
 mm/page_alloc.c |  2 +-
 mm/sparse.c | 25 -
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2e5dcfdb0908..ae9023da2ca2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8013,7 +8013,6 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
break;
if (pfn == end_pfn)
return;
-   offline_mem_sections(pfn, end_pfn);
zone = page_zone(pfn_to_page(pfn));
spin_lock_irqsave(>lock, flags);
pfn = start_pfn;
@@ -8051,6 +8050,7 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
pfn += (1 << order);
}
spin_unlock_irqrestore(>lock, flags);
+   offline_mem_sections(start_pfn, end_pfn);
 }
 #endif
 
diff --git a/mm/sparse.c b/mm/sparse.c
index 58cab483e81b..44978cb18fed 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -623,7 +623,27 @@ void online_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-/* Mark all memory sections within the pfn range as online */
+static bool all_pages_in_section_offline(unsigned long section_nr)
+{
+   unsigned long pfn = section_nr_to_pfn(section_nr);
+   struct page *page;
+   int i;
+
+   for (i = 0; i < PAGES_PER_SECTION; i++, pfn++) {
+   if (!pfn_valid(pfn))
+   continue;
+
+   page = pfn_to_page(pfn);
+   if (!PageOffline(page))
+   return false;
+   }
+   return true;
+}
+
+/*
+ * Mark all memory sections within the pfn range as offline (if all pages
+ * of a memory section are already offline)
+ */
 void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
 {
unsigned long pfn;
@@ -639,6 +659,9 @@ void offline_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
if (WARN_ON(!valid_section_nr(section_nr)))
continue;
 
+   if (!all_pages_in_section_offline(section_nr))
+   continue;
+
ms = __nr_to_section(section_nr);
ms->section_mem_map &= ~SECTION_IS_ONLINE;
}
-- 
2.14.3

[PATCH RFC 5/8] mm: only mark section offline when all pages are offline

[David Hildenbrand]

If any page is still online, the section should stay online.

Signed-off-by: David Hildenbrand 
---
 mm/page_alloc.c |  2 +-
 mm/sparse.c | 25 -
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2e5dcfdb0908..ae9023da2ca2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8013,7 +8013,6 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
break;
if (pfn == end_pfn)
return;
-   offline_mem_sections(pfn, end_pfn);
zone = page_zone(pfn_to_page(pfn));
spin_lock_irqsave(>lock, flags);
pfn = start_pfn;
@@ -8051,6 +8050,7 @@ __offline_isolated_pages(unsigned long start_pfn, 
unsigned long end_pfn)
pfn += (1 << order);
}
spin_unlock_irqrestore(>lock, flags);
+   offline_mem_sections(start_pfn, end_pfn);
 }
 #endif
 
diff --git a/mm/sparse.c b/mm/sparse.c
index 58cab483e81b..44978cb18fed 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -623,7 +623,27 @@ void online_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-/* Mark all memory sections within the pfn range as online */
+static bool all_pages_in_section_offline(unsigned long section_nr)
+{
+   unsigned long pfn = section_nr_to_pfn(section_nr);
+   struct page *page;
+   int i;
+
+   for (i = 0; i < PAGES_PER_SECTION; i++, pfn++) {
+   if (!pfn_valid(pfn))
+   continue;
+
+   page = pfn_to_page(pfn);
+   if (!PageOffline(page))
+   return false;
+   }
+   return true;
+}
+
+/*
+ * Mark all memory sections within the pfn range as offline (if all pages
+ * of a memory section are already offline)
+ */
 void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
 {
unsigned long pfn;
@@ -639,6 +659,9 @@ void offline_mem_sections(unsigned long start_pfn, unsigned 
long end_pfn)
if (WARN_ON(!valid_section_nr(section_nr)))
continue;
 
+   if (!all_pages_in_section_offline(section_nr))
+   continue;
+
ms = __nr_to_section(section_nr);
ms->section_mem_map &= ~SECTION_IS_ONLINE;
}
-- 
2.14.3