mm: move function ‘is_pageblock_removable_nolock’ inside blockers

PATCH In review Mathieu Malaterre 2 participants 4 messages May 5, 2018 – May 10, 2018

Subsystems (3)

Memory management Page allocator Memory hot(un)plug

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Mathieu Malaterre

author

2018-05-05 20:11 UTC #0 lore raw

PATCH 1/1 mm: move function ‘is_pageblock_removable_nolock’ inside blockers

Function a??is_pageblock_removable_nolocka?? is not used unless CONFIG_MEMORY_HOTREMOVE is activated. Move it in between #ifdef sentinel to match prototype in <linux/memory_hotplug.h>. Silence gcc warning (W=1):

mm/page_alloc.c:7704:6: warning: no previous prototype for a??is_pageblock_removable_nolocka?? [-Wmissing-prototypes]

Signed-off-by Mathieu Malaterre <[email protected]>

---
 mm/page_alloc.c | 2 ++
 1 file changed, 2 insertions(+)

mm/page_alloc.c +2 -0

index 905db9d7962f..94ca579938e5 100644
@@ -7701,6 +7701,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return false;
 }
 
+#ifdef CONFIG_MEMORY_HOTREMOVE
 bool is_pageblock_removable_nolock(struct page *page)
 {
 	struct zone *zone;

@@ -7723,6 +7724,7 @@ bool is_pageblock_removable_nolock(struct page *page)
 
 	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
 }
+#endif
 
 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)

Signature · 1 line

2.11.0

Michal Hocko

2018-05-09 07:44 UTC #1 lore raw

Quoted 5 lines · Mathieu Malaterre

Function a??is_pageblock_removable_nolocka?? is not used unless CONFIG_MEMORY_HOTREMOVE is activated. Move it in between #ifdef sentinel to match prototype in <linux/memory_hotplug.h>. Silence gcc warning (W=1):
mm/page_alloc.c:7704:6: warning: no previous prototype for a??is_pageblock_removable_nolocka?? [-Wmissing-prototypes]

Could you move is_pageblock_removable_nolock to mm/memory_hotplug.c and make it static instead? There is only one caller is_mem_section_removable so there shouldn't be any real reason to have it extern and add more ifdefs.

Quoted 28 lines

Signed-off-by Mathieu Malaterre <[email protected]>

---
 mm/page_alloc.c | 2 ++
 1 file changed, 2 insertions(+)

mm/page_alloc.c +2 -0

index 905db9d7962f..94ca579938e5 100644
@@ -7701,6 +7701,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return false;
 }
 
+#ifdef CONFIG_MEMORY_HOTREMOVE
 bool is_pageblock_removable_nolock(struct page *page)
 {
 	struct zone *zone;

@@ -7723,6 +7724,7 @@ bool is_pageblock_removable_nolock(struct page *page)
 
 	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
 }
+#endif
 
 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)

Signature · 1 line

2.11.0

Signature · 2 lines

Michal Hocko
SUSE Labs

Mathieu Malaterre

author

2018-05-09 18:59 UTC #2 lore raw

PATCH v2 1/1 mm: move function ‘is_pageblock_removable_nolock’ to mm/memory_hotplug.c

In reply to Mathieu Malaterre

Function ‘is_pageblock_removable_nolock’ is not used outside of mm/memory_hotplug.c. Move it next to unique caller:
‘is_mem_section_removable’ and make it static.
Remove prototype in <linux/memory_hotplug.h>. Silence gcc warning (W=1):

mm/page_alloc.c:7704:6: warning: no previous prototype for ‘is_pageblock_removable_nolock’ [-Wmissing-prototypes]

Signed-off-by Mathieu Malaterre <[email protected]>

---
v2: this function can be made static, make it so

 include/linux/memory_hotplug.h |  1 -
 mm/memory_hotplug.c            | 23 +++++++++++++++++++++++
 mm/page_alloc.c                | 23 -----------------------
 3 files changed, 23 insertions(+), 24 deletions(-)

include/linux/memory_hotplug.h +0 -1

index e0e49b5b1ee1..9566d551a41b 100644
@@ -107,7 +107,6 @@ static inline bool movable_node_is_enabled(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-extern bool is_pageblock_removable_nolock(struct page *page);
 extern int arch_remove_memory(u64 start, u64 size,
 		struct vmem_altmap *altmap);
 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,

mm/memory_hotplug.c +23 -0

index f74826cdceea..9342e120518a 100644
@@ -1237,6 +1237,29 @@ static struct page *next_active_pageblock(struct page *page)
 	return page + pageblock_nr_pages;
 }
 
+static bool is_pageblock_removable_nolock(struct page *page)
+{
+	struct zone *zone;
+	unsigned long pfn;
+
+	/*
+	 * We have to be careful here because we are iterating over memory
+	 * sections which are not zone aware so we might end up outside of
+	 * the zone but still within the section.
+	 * We have to take care about the node as well. If the node is offline
+	 * its NODE_DATA will be NULL - see page_zone.
+	 */
+	if (!node_online(page_to_nid(page)))
+		return false;
+
+	zone = page_zone(page);
+	pfn = page_to_pfn(page);
+	if (!zone_spans_pfn(zone, pfn))
+		return false;
+
+	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
+}
+
 /* Checks if this range of memory is likely to be hot-removable. */
 bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
 {

mm/page_alloc.c +0 ~~-23~~

index 905db9d7962f..52731601ca5a 100644
@@ -7701,29 +7701,6 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return false;
 }
 
-bool is_pageblock_removable_nolock(struct page *page)
-{
-	struct zone *zone;
-	unsigned long pfn;
-
-	/*
-	 * We have to be careful here because we are iterating over memory
-	 * sections which are not zone aware so we might end up outside of
-	 * the zone but still within the section.
-	 * We have to take care about the node as well. If the node is offline
-	 * its NODE_DATA will be NULL - see page_zone.
-	 */
-	if (!node_online(page_to_nid(page)))
-		return false;
-
-	zone = page_zone(page);
-	pfn = page_to_pfn(page);
-	if (!zone_spans_pfn(zone, pfn))
-		return false;
-
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
-}
-
 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
 
 static unsigned long pfn_max_align_down(unsigned long pfn)

Signature · 1 line

2.11.0

Michal Hocko

Acked-by on v2 1/1

2018-05-10 08:36 UTC #3 lore raw

Re: [PATCH v2] mm: move function ‘is_pageblock_removable_nolock’ to mm/memory_hotplug.c

Quoted 9 lines · Mathieu Malaterre

Function ‘is_pageblock_removable_nolock’ is not used outside of mm/memory_hotplug.c. Move it next to unique caller:
‘is_mem_section_removable’ and make it static.
Remove prototype in <linux/memory_hotplug.h>. Silence gcc warning (W=1):
mm/page_alloc.c:7704:6: warning: no previous prototype for ‘is_pageblock_removable_nolock’ [-Wmissing-prototypes]
Suggested-by Michal Hocko <[email protected]>
Signed-off-by Mathieu Malaterre <[email protected]>

Acked-by Michal Hocko <[email protected]>

Thanks!

Quoted 91 lines

---
v2: this function can be made static, make it so

 include/linux/memory_hotplug.h |  1 -
 mm/memory_hotplug.c            | 23 +++++++++++++++++++++++
 mm/page_alloc.c                | 23 -----------------------
 3 files changed, 23 insertions(+), 24 deletions(-)

include/linux/memory_hotplug.h +0 -1

index e0e49b5b1ee1..9566d551a41b 100644
@@ -107,7 +107,6 @@ static inline bool movable_node_is_enabled(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-extern bool is_pageblock_removable_nolock(struct page *page);
 extern int arch_remove_memory(u64 start, u64 size,
 		struct vmem_altmap *altmap);
 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,

mm/memory_hotplug.c +23 -0

index f74826cdceea..9342e120518a 100644
@@ -1237,6 +1237,29 @@ static struct page *next_active_pageblock(struct page *page)
 	return page + pageblock_nr_pages;
 }
 
+static bool is_pageblock_removable_nolock(struct page *page)
+{
+	struct zone *zone;
+	unsigned long pfn;
+
+	/*
+	 * We have to be careful here because we are iterating over memory
+	 * sections which are not zone aware so we might end up outside of
+	 * the zone but still within the section.
+	 * We have to take care about the node as well. If the node is offline
+	 * its NODE_DATA will be NULL - see page_zone.
+	 */
+	if (!node_online(page_to_nid(page)))
+		return false;
+
+	zone = page_zone(page);
+	pfn = page_to_pfn(page);
+	if (!zone_spans_pfn(zone, pfn))
+		return false;
+
+	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
+}
+
 /* Checks if this range of memory is likely to be hot-removable. */
 bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
 {

mm/page_alloc.c +0 ~~-23~~

index 905db9d7962f..52731601ca5a 100644
@@ -7701,29 +7701,6 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 	return false;
 }
 
-bool is_pageblock_removable_nolock(struct page *page)
-{
-	struct zone *zone;
-	unsigned long pfn;
-
-	/*
-	 * We have to be careful here because we are iterating over memory
-	 * sections which are not zone aware so we might end up outside of
-	 * the zone but still within the section.
-	 * We have to take care about the node as well. If the node is offline
-	 * its NODE_DATA will be NULL - see page_zone.
-	 */
-	if (!node_online(page_to_nid(page)))
-		return false;
-
-	zone = page_zone(page);
-	pfn = page_to_pfn(page);
-	if (!zone_spans_pfn(zone, pfn))
-		return false;
-
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
-}
-
 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
 
 static unsigned long pfn_max_align_down(unsigned long pfn)

Signature · 1 line

2.11.0

Signature · 2 lines

Michal Hocko
SUSE Labs