Subject: [PATCH v1 5/5] mm/memory_hotplug: Remove zone parameter from __remove_pages()

From: David Hildenbrand <[email-masked]>
Date: Wed, 21 Aug 2019 17:40:06 +0200

No longer in use, let's drop it. We no longer access the zone of
possibly never onlined memory (and therefore don't read garabage in
these scenarios).

Cc: Catalin Marinas <[email-masked]>
Cc: Will Deacon <[email-masked]>
Cc: Tony Luck <[email-masked]>
Cc: Fenghua Yu <[email-masked]>
Cc: Benjamin Herrenschmidt <[email-masked]>
Cc: Paul Mackerras <[email-masked]>
Cc: Michael Ellerman <[email-masked]>
Cc: Heiko Carstens <[email-masked]>
Cc: Vasily Gorbik <[email-masked]>
Cc: Christian Borntraeger <[email-masked]>
Cc: Yoshinori Sato <[email-masked]>
Cc: Rich Felker <[email-masked]>
Cc: Dave Hansen <[email-masked]>
Cc: Andy Lutomirski <[email-masked]>
Cc: Peter Zijlstra <[email-masked]>
Cc: Thomas Gleixner <[email-masked]>
Cc: Ingo Molnar <[email-masked]>
Cc: Borislav Petkov <[email-masked]>
Cc: "H. Peter Anvin" <[email-masked]>
Cc: [email-masked]
Cc: Andrew Morton <[email-masked]>
Cc: Mark Rutland <[email-masked]>
Cc: Steve Capper <[email-masked]>
Cc: Mike Rapoport <[email-masked]>
Cc: Anshuman Khandual <[email-masked]>
Cc: Yu Zhao <[email-masked]>
Cc: Jun Yao <[email-masked]>
Cc: Robin Murphy <[email-masked]>
Cc: Michal Hocko <[email-masked]>
Cc: Oscar Salvador <[email-masked]>
Cc: "Matthew Wilcox (Oracle)" <[email-masked]>
Cc: Christophe Leroy <[email-masked]>
Cc: "Aneesh Kumar K.V" <[email-masked]>
Cc: Pavel Tatashin <[email-masked]>
Cc: Gerald Schaefer <[email-masked]>
Cc: Halil Pasic <[email-masked]>
Cc: Tom Lendacky <[email-masked]>
Cc: Greg Kroah-Hartman <[email-masked]>
Cc: Masahiro Yamada <[email-masked]>
Cc: Dan Williams <[email-masked]>
Cc: Wei Yang <[email-masked]>
Cc: Qian Cai <[email-masked]>
Cc: Jason Gunthorpe <[email-masked]>
Cc: Logan Gunthorpe <[email-masked]>
Cc: Ira Weiny <[email-masked]>
Cc: [email-masked]
Cc: [email-masked]
Cc: [email-masked]
Cc: [email-masked]
Cc: [email-masked]
Signed-off-by: David Hildenbrand <[email-masked]>
---
 arch/arm64/mm/mmu.c            | 4 +---
 arch/ia64/mm/init.c            | 4 +---
 arch/powerpc/mm/mem.c          | 3 +--
 arch/s390/mm/init.c            | 4 +---
 arch/sh/mm/init.c              | 4 +---
 arch/x86/mm/init_32.c          | 4 +---
 arch/x86/mm/init_64.c          | 4 +---
 include/linux/memory_hotplug.h | 4 ++--
 mm/memory_hotplug.c            | 6 +++---
 mm/memremap.c                  | 3 +--
 10 files changed, 13 insertions(+), 27 deletions(-)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index e67bab4d613e..b3843aff12bf 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1080,7 +1080,6 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
 	/*
 	 * FIXME: Cleanup page tables (also in arch_add_memory() in case
@@ -1089,7 +1088,6 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 	 * unplug. ARCH_ENABLE_MEMORY_HOTREMOVE must not be
 	 * unlocked yet.
 	 */
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index bf9df2625bc8..a6dd80a2c939 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -689,9 +689,7 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 9191a66b3bc5..7351c44c435a 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -130,10 +130,9 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
 	int ret;
 
-	__remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 
 	/* Remove htab bolted mappings for this section of memory */
 	start = (unsigned long)__va(start);
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 20340a03ad90..6f13eb66e375 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -296,10 +296,8 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 	vmem_remove_mapping(start, size);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index dfdbaa50946e..d1b1ff2be17a 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -434,9 +434,7 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = PFN_DOWN(start);
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 4068abb9427f..9d036be27aaa 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -865,10 +865,8 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
 
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a6b5c653727b..b8541d77452c 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1212,10 +1212,8 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
-	struct zone *zone = page_zone(page);
 
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 	kernel_physical_mapping_remove(start, start + size);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index f46ea71b4ffd..f75d9483864f 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -125,8 +125,8 @@ static inline bool movable_node_is_enabled(void)
 
 extern void arch_remove_memory(int nid, u64 start, u64 size,
 			       struct vmem_altmap *altmap);
-extern void __remove_pages(struct zone *zone, unsigned long start_pfn,
-			   unsigned long nr_pages, struct vmem_altmap *altmap);
+extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
+			   struct vmem_altmap *altmap);
 
 /* reasonably generic interface to expand the physical pages */
 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index e88c96cf9d77..7a9719a762fe 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -532,7 +532,6 @@ static void __remove_section(unsigned long pfn, unsigned long nr_pages,
 
 /**
  * __remove_pages() - remove sections of pages from a zone
- * @zone: zone from which pages need to be removed
  * @pfn: starting pageframe (must be aligned to start of a section)
  * @nr_pages: number of pages to remove (must be multiple of section size)
  * @altmap: alternative device page map or %NULL if default memmap is used
@@ -542,12 +541,13 @@ static void __remove_section(unsigned long pfn, unsigned long nr_pages,
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-void __remove_pages(struct zone *zone, unsigned long pfn,
-		    unsigned long nr_pages, struct vmem_altmap *altmap)
+void __remove_pages(unsigned long pfn, unsigned long nr_pages,
+		    struct vmem_altmap *altmap)
 {
 	const unsigned long end_pfn = pfn + nr_pages;
 	unsigned long cur_nr_pages;
 	unsigned long map_offset = 0;
+	struct zone *zone;
 
 	if (check_pfn_span(pfn, nr_pages, "remove"))
 		return;
diff --git a/mm/memremap.c b/mm/memremap.c
index 8a394552b5bd..7e34f42e5f5a 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -138,8 +138,7 @@ static void devm_memremap_pages_release(void *data)
 	mem_hotplug_begin();
 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
 		pfn = PHYS_PFN(res->start);
-		__remove_pages(page_zone(pfn_to_page(pfn)), pfn,
-				 PHYS_PFN(resource_size(res)), NULL);
+		__remove_pages(pfn, PHYS_PFN(resource_size(res)), NULL);
 	} else {
 		arch_remove_memory(nid, res->start, resource_size(res),
 				pgmap_altmap(pgmap));
-- 
2.21.0