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mm, hotplug: avoid compiling memory hotremove functions when disabled

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__remove_pages() is only necessary for CONFIG_MEMORY_HOTREMOVE.  PowerPC
pseries will return -EOPNOTSUPP if unsupported.

Adding an #ifdef causes several other functions it depends on to also
become unnecessary, which saves in .text when disabled (it's disabled in
most defconfigs besides powerpc, including x86).  remove_memory_block()
becomes static since it is not referenced outside of
drivers/base/memory.c.

Build tested on x86 and powerpc with CONFIG_MEMORY_HOTREMOVE both enabled
and disabled.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2013-04-29 15:08:22 -07:00 committed by Linus Torvalds
parent fe74ebb106
commit 4edd7ceff0
6 changed files with 113 additions and 90 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

12
arch/powerpc/platforms/pseries/hotplug-memory.c
View file

@ -72,6 +72,7 @@ unsigned long memory_block_size_bytes(void)
return get_memblock_size();
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
{
unsigned long start, start_pfn;
@ -153,6 +154,17 @@ static int pseries_remove_memory(struct device_node *np)
ret = pseries_remove_memblock(base, lmb_size);
return ret;
}
#else
static inline int pseries_remove_memblock(unsigned long base,
unsigned int memblock_size)
{
return -EOPNOTSUPP;
}
static inline int pseries_remove_memory(struct device_node *np)
{
return -EOPNOTSUPP;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
static int pseries_add_memory(struct device_node *np)
{

44
drivers/base/memory.c
View file

@ -93,16 +93,6 @@ int register_memory(struct memory_block *memory)
return error;
}
static void
unregister_memory(struct memory_block *memory)
{
BUG_ON(memory->dev.bus != &memory_subsys);
/* drop the ref. we got in remove_memory_block() */
kobject_put(&memory->dev.kobj);
device_unregister(&memory->dev);
}
unsigned long __weak memory_block_size_bytes(void)
{
return MIN_MEMORY_BLOCK_SIZE;
@ -637,8 +627,28 @@ static int add_memory_section(int nid, struct mem_section *section,
return ret;
}
int remove_memory_block(unsigned long node_id, struct mem_section *section,
int phys_device)
/*
* need an interface for the VM to add new memory regions,
* but without onlining it.
*/
int register_new_memory(int nid, struct mem_section *section)
{
return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static void
unregister_memory(struct memory_block *memory)
{
BUG_ON(memory->dev.bus != &memory_subsys);
/* drop the ref. we got in remove_memory_block() */
kobject_put(&memory->dev.kobj);
device_unregister(&memory->dev);
}
static int remove_memory_block(unsigned long node_id,
struct mem_section *section, int phys_device)
{
struct memory_block *mem;
@ -661,15 +671,6 @@ int remove_memory_block(unsigned long node_id, struct mem_section *section,
return 0;
}
/*
* need an interface for the VM to add new memory regions,
* but without onlining it.
*/
int register_new_memory(int nid, struct mem_section *section)
{
return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
}
int unregister_memory_section(struct mem_section *section)
{
if (!present_section(section))
@ -677,6 +678,7 @@ int unregister_memory_section(struct mem_section *section)
return remove_memory_block(0, section, 0);
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
/*
* offline one memory block. If the memory block has been offlined, do nothing.

3
include/linux/memory.h
View file

@ -115,9 +115,10 @@ extern void unregister_memory_notifier(struct notifier_block *nb);
extern int register_memory_isolate_notifier(struct notifier_block *nb);
extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
extern int register_new_memory(int, struct mem_section *);
#ifdef CONFIG_MEMORY_HOTREMOVE
extern int unregister_memory_section(struct mem_section *);
#endif
extern int memory_dev_init(void);
extern int remove_memory_block(unsigned long, struct mem_section *, int);
extern int memory_notify(unsigned long val, void *v);
extern int memory_isolate_notify(unsigned long val, void *v);
extern struct memory_block *find_memory_block_hinted(struct mem_section *,

4
include/linux/memory_hotplug.h
View file

@ -97,13 +97,13 @@ extern void __online_page_free(struct page *page);
#ifdef CONFIG_MEMORY_HOTREMOVE
extern bool is_pageblock_removable_nolock(struct page *page);
extern int arch_remove_memory(u64 start, u64 size);
extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages);
#endif /* CONFIG_MEMORY_HOTREMOVE */
/* reasonably generic interface to expand the physical pages in a zone */
extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages);
extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages);
#ifdef CONFIG_NUMA
extern int memory_add_physaddr_to_nid(u64 start);

68
mm/memory_hotplug.c
View file

@ -436,6 +436,40 @@ static int __meminit __add_section(int nid, struct zone *zone,
return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
}
/*
* Reasonably generic function for adding memory. It is
* expected that archs that support memory hotplug will
* call this function after deciding the zone to which to
* add the new pages.
*/
int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i;
int err = 0;
int start_sec, end_sec;
/* during initialize mem_map, align hot-added range to section */
start_sec = pfn_to_section_nr(phys_start_pfn);
end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
for (i = start_sec; i <= end_sec; i++) {
err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
/*
* EEXIST is finally dealt with by ioresource collision
* check. see add_memory() => register_memory_resource()
* Warning will be printed if there is collision.
*/
if (err && (err != -EEXIST))
break;
err = 0;
}
return err;
}
EXPORT_SYMBOL_GPL(__add_pages);
#ifdef CONFIG_MEMORY_HOTREMOVE
/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
static int find_smallest_section_pfn(int nid, struct zone *zone,
unsigned long start_pfn,
@ -658,39 +692,6 @@ static int __remove_section(struct zone *zone, struct mem_section *ms)
return 0;
}
/*
* Reasonably generic function for adding memory. It is
* expected that archs that support memory hotplug will
* call this function after deciding the zone to which to
* add the new pages.
*/
int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i;
int err = 0;
int start_sec, end_sec;
/* during initialize mem_map, align hot-added range to section */
start_sec = pfn_to_section_nr(phys_start_pfn);
end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
for (i = start_sec; i <= end_sec; i++) {
err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
/*
* EEXIST is finally dealt with by ioresource collision
* check. see add_memory() => register_memory_resource()
* Warning will be printed if there is collision.
*/
if (err && (err != -EEXIST))
break;
err = 0;
}
return err;
}
EXPORT_SYMBOL_GPL(__add_pages);
/**
* __remove_pages() - remove sections of pages from a zone
* @zone: zone from which pages need to be removed
@ -733,6 +734,7 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
return ret;
}
EXPORT_SYMBOL_GPL(__remove_pages);
#endif /* CONFIG_MEMORY_HOTREMOVE */
int set_online_page_callback(online_page_callback_t callback)
{

72
mm/sparse.c
View file

@ -620,6 +620,7 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
vmemmap_free(start, end);
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
{
unsigned long start = (unsigned long)memmap;
@ -627,6 +628,7 @@ static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
vmemmap_free(start, end);
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
#else
static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
{
@ -664,6 +666,7 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
get_order(sizeof(struct page) * nr_pages));
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
{
unsigned long maps_section_nr, removing_section_nr, i;
@ -690,40 +693,9 @@ static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
put_page_bootmem(page);
}
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
#endif /* CONFIG_SPARSEMEM_VMEMMAP */
static void free_section_usemap(struct page *memmap, unsigned long *usemap)
{
struct page *usemap_page;
unsigned long nr_pages;
if (!usemap)
return;
usemap_page = virt_to_page(usemap);
/*
* Check to see if allocation came from hot-plug-add
*/
if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
kfree(usemap);
if (memmap)
__kfree_section_memmap(memmap, PAGES_PER_SECTION);
return;
}
/*
* The usemap came from bootmem. This is packed with other usemaps
* on the section which has pgdat at boot time. Just keep it as is now.
*/
if (memmap) {
nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
>> PAGE_SHIFT;
free_map_bootmem(memmap, nr_pages);
}
}
/*
* returns the number of sections whose mem_maps were properly
* set. If this is <=0, then that means that the passed-in
@ -800,6 +772,39 @@ static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
}
#endif
#ifdef CONFIG_MEMORY_HOTREMOVE
static void free_section_usemap(struct page *memmap, unsigned long *usemap)
{
struct page *usemap_page;
unsigned long nr_pages;
if (!usemap)
return;
usemap_page = virt_to_page(usemap);
/*
* Check to see if allocation came from hot-plug-add
*/
if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
kfree(usemap);
if (memmap)
__kfree_section_memmap(memmap, PAGES_PER_SECTION);
return;
}
/*
* The usemap came from bootmem. This is packed with other usemaps
* on the section which has pgdat at boot time. Just keep it as is now.
*/
if (memmap) {
nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
>> PAGE_SHIFT;
free_map_bootmem(memmap, nr_pages);
}
}
void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
{
struct page *memmap = NULL;
@ -819,4 +824,5 @@ void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
clear_hwpoisoned_pages(memmap, PAGES_PER_SECTION);
free_section_usemap(memmap, usemap);
}
#endif
#endif /* CONFIG_MEMORY_HOTREMOVE */
#endif /* CONFIG_MEMORY_HOTPLUG */