[RFC PATCH 1/3] mm/memory_hotplug: Add nid parameter to arch_remove_memory

From: osalvador
Date: Tue Aug 07 2018 - 09:38:27 EST


From: Oscar Salvador <osalvador@xxxxxxx>

This patch is only a preparation for the following-up patches.
The idea is to remove the zone parameter and pass the nid instead.
The zone parameter was needed because down the chain we call
__remove_zone, which adjusts the spanned pages of a zone/node.

online_pages() increments the spanned pages of a zone/node, so
for consistency it is better if we move __remove_zone to offline_pages().
With that, remove_memory() will only take care of removing the sections
and delete the mappings.

Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
---
arch/ia64/mm/init.c | 2 +-
arch/powerpc/mm/mem.c | 2 +-
arch/s390/mm/init.c | 2 +-
arch/sh/mm/init.c | 2 +-
arch/x86/mm/init_32.c | 2 +-
arch/x86/mm/init_64.c | 2 +-
include/linux/memory_hotplug.h | 2 +-
kernel/memremap.c | 4 +++-
mm/hmm.c | 4 +++-
mm/memory_hotplug.c | 2 +-
10 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index e6c6dfd98de2..bc5e15045cee 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -660,7 +660,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 5c8530d0c611..9e17d57a9948 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -139,7 +139,7 @@ int __meminit arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-int __meminit arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int __meminit arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 3fa3e5323612..bc49b560625e 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -240,7 +240,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
/*
* There is no hardware or firmware interface which could trigger a
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index 4034035fbede..55c740ab861b 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -454,7 +454,7 @@ EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
#endif

#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = PFN_DOWN(start);
unsigned long nr_pages = size >> PAGE_SHIFT;
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 979e0a02cbe1..9fa503f2f56c 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -861,7 +861,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 9b19f9a8948e..26728df07072 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1148,7 +1148,7 @@ kernel_physical_mapping_remove(unsigned long start, unsigned long end)
remove_pagetable(start, end, true, NULL);
}

-int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
+int __ref arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 34a28227068d..c68b03fd87bd 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -107,7 +107,7 @@ static inline bool movable_node_is_enabled(void)
}

#ifdef CONFIG_MEMORY_HOTREMOVE
-extern int arch_remove_memory(u64 start, u64 size,
+extern int arch_remove_memory(int nid, u64 start, u64 size,
struct vmem_altmap *altmap);
extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages, struct vmem_altmap *altmap);
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 5b8600d39931..7a832b844f24 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -121,6 +121,7 @@ static void devm_memremap_pages_release(void *data)
struct resource *res = &pgmap->res;
resource_size_t align_start, align_size;
unsigned long pfn;
+ int nid;

for_each_device_pfn(pfn, pgmap)
put_page(pfn_to_page(pfn));
@@ -134,9 +135,10 @@ static void devm_memremap_pages_release(void *data)
align_start = res->start & ~(SECTION_SIZE - 1);
align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
- align_start;
+ nid = dev_to_node(dev);

mem_hotplug_begin();
- arch_remove_memory(align_start, align_size, pgmap->altmap_valid ?
+ arch_remove_memory(nid, align_start, align_size, pgmap->altmap_valid ?
&pgmap->altmap : NULL);
kasan_remove_zero_shadow(__va(align_start), align_size);
mem_hotplug_done();
diff --git a/mm/hmm.c b/mm/hmm.c
index c968e49f7a0c..21787e480b4a 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -995,6 +995,7 @@ static void hmm_devmem_release(struct device *dev, void *data)
unsigned long start_pfn, npages;
struct zone *zone;
struct page *page;
+ int nid;

if (percpu_ref_tryget_live(&devmem->ref)) {
dev_WARN(dev, "%s: page mapping is still live!\n", __func__);
@@ -1007,12 +1008,13 @@ static void hmm_devmem_release(struct device *dev, void *data)

page = pfn_to_page(start_pfn);
zone = page_zone(page);
+ nid = zone->zone_pgdat->node_id;

mem_hotplug_begin();
if (resource->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY)
__remove_pages(zone, start_pfn, npages, NULL);
else
- arch_remove_memory(start_pfn << PAGE_SHIFT,
+ arch_remove_memory(nid, start_pfn << PAGE_SHIFT,
npages << PAGE_SHIFT, NULL);
mem_hotplug_done();

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9eea6e809a4e..9bd629944c91 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1895,7 +1895,7 @@ void __ref remove_memory(int nid, u64 start, u64 size)
memblock_free(start, size);
memblock_remove(start, size);

- arch_remove_memory(start, size, NULL);
+ arch_remove_memory(nid, start, size, NULL);

try_offline_node(nid);

--
2.13.6