Skip to content

Commit

Permalink
[PATCH] x86_64: Support memory hotadd without sparsemem
Browse files Browse the repository at this point in the history
Memory hotadd doesn't need SPARSEMEM, but can be handled by just preallocating
mem_maps. This only needs some untangling of ifdefs to enable the necessary
code even without SPARSEMEM.

Originally from Keith Mannthey, hacked by AK.

Signed-off-by: Andi Kleen <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
  • Loading branch information
Andi Kleen authored and Linus Torvalds committed Apr 9, 2006
1 parent 805e8c0 commit 9d99aaa
Show file tree
Hide file tree
Showing 6 changed files with 47 additions and 12 deletions.
2 changes: 2 additions & 0 deletions arch/i386/mm/init.c
Original file line number Diff line number Diff line change
Expand Up @@ -651,6 +651,7 @@ void __init mem_init(void)
* Specifically, in the case of x86, we will always add
* memory to the highmem for now.
*/
#ifdef CONFIG_HOTPLUG_MEMORY
#ifndef CONFIG_NEED_MULTIPLE_NODES
int add_memory(u64 start, u64 size)
{
Expand All @@ -667,6 +668,7 @@ int remove_memory(u64 start, u64 size)
return -EINVAL;
}
#endif
#endif

kmem_cache_t *pgd_cache;
kmem_cache_t *pmd_cache;
Expand Down
2 changes: 1 addition & 1 deletion arch/x86_64/kernel/e820.c
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@ static inline int bad_addr(unsigned long *addrp, unsigned long size)
return 0;
}

int __init e820_mapped(unsigned long start, unsigned long end, unsigned type)
int __meminit e820_mapped(unsigned long start, unsigned long end, unsigned type)
{
int i;
for (i = 0; i < e820.nr_map; i++) {
Expand Down
36 changes: 34 additions & 2 deletions arch/x86_64/mm/init.c
Original file line number Diff line number Diff line change
Expand Up @@ -507,9 +507,8 @@ void __init clear_kernel_mapping(unsigned long address, unsigned long size)

/*
* Memory hotplug specific functions
* These are only for non-NUMA machines right now.
*/
#ifdef CONFIG_MEMORY_HOTPLUG
#if defined(CONFIG_ACPI_HOTPLUG_MEMORY) || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)

void online_page(struct page *page)
{
Expand All @@ -520,6 +519,39 @@ void online_page(struct page *page)
num_physpages++;
}

#ifndef CONFIG_MEMORY_HOTPLUG
/*
* Memory Hotadd without sparsemem. The mem_maps have been allocated in advance,
* just online the pages.
*/
int __add_pages(struct zone *z, unsigned long start_pfn, unsigned long nr_pages)
{
int err = -EIO;
unsigned long pfn;
unsigned long total = 0, mem = 0;
for (pfn = start_pfn; pfn < start_pfn + nr_pages; pfn++) {
unsigned long addr = pfn << PAGE_SHIFT;
if (pfn_valid(pfn) && e820_mapped(addr, addr+1, E820_RAM)) {
online_page(pfn_to_page(pfn));
err = 0;
mem++;
}
total++;
}
if (!err) {
z->spanned_pages += total;
z->present_pages += mem;
z->zone_pgdat->node_spanned_pages += total;
z->zone_pgdat->node_present_pages += mem;
}
return err;
}
#endif

/*
* Memory is added always to NORMAL zone. This means you will never get
* additional DMA/DMA32 memory.
*/
int add_memory(u64 start, u64 size)
{
struct pglist_data *pgdat = NODE_DATA(0);
Expand Down
2 changes: 1 addition & 1 deletion drivers/acpi/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -329,7 +329,7 @@ config ACPI_CONTAINER
config ACPI_HOTPLUG_MEMORY
tristate "Memory Hotplug"
depends on ACPI
depends on MEMORY_HOTPLUG
depends on MEMORY_HOTPLUG || X86_64
default n
help
This driver adds supports for ACPI Memory Hotplug. This driver
Expand Down
3 changes: 2 additions & 1 deletion include/linux/init.h
Original file line number Diff line number Diff line change
Expand Up @@ -245,7 +245,8 @@ void __init parse_early_param(void);
#define __cpuexitdata __exitdata
#endif

#ifdef CONFIG_MEMORY_HOTPLUG
#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
|| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
#define __meminit
#define __meminitdata
#define __memexit
Expand Down
14 changes: 7 additions & 7 deletions include/linux/memory_hotplug.h
Original file line number Diff line number Diff line change
Expand Up @@ -58,8 +58,6 @@ extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
/* need some defines for these for archs that don't support it */
extern void online_page(struct page *page);
/* VM interface that may be used by firmware interface */
extern int add_memory(u64 start, u64 size);
extern int remove_memory(u64 start, u64 size);
extern int online_pages(unsigned long, unsigned long);

/* reasonably generic interface to expand the physical pages in a zone */
Expand Down Expand Up @@ -92,11 +90,6 @@ static inline int mhp_notimplemented(const char *func)
return -ENOSYS;
}

static inline int __add_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages)
{
return mhp_notimplemented(__FUNCTION__);
}
#endif /* ! CONFIG_MEMORY_HOTPLUG */
static inline int __remove_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages)
Expand All @@ -105,4 +98,11 @@ static inline int __remove_pages(struct zone *zone, unsigned long start_pfn,
dump_stack();
return -ENOSYS;
}

#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
|| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
extern int add_memory(u64 start, u64 size);
extern int remove_memory(u64 start, u64 size);
#endif

#endif /* __LINUX_MEMORY_HOTPLUG_H */

0 comments on commit 9d99aaa

Please sign in to comment.