[PATCH] x86_64: Support memory hotadd without sparsemem

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 <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] x86_64: Support memory hotadd without sparsemem
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 <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Andi Kleen · Linus Torvalds
1 parent 805e8c03c9
Showing 6 changed files with 47 additions and 12 deletions Side-by-side Diff
arch/i386/mm/init.c
arch/x86_64/kernel/e820.c
arch/x86_64/mm/init.c
drivers/acpi/Kconfig
include/linux/init.h
include/linux/memory_hotplug.h
@@ -651,6 +651,7 @@
  * 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)
 {
@@ -666,6 +667,7 @@
 {
 	return -EINVAL;
 }
+#endif
 #endif
  
 kmem_cache_t *pgd_cache;
@@ -80,7 +80,7 @@
 	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++) { 
@@ -507,9 +507,8 @@
  
 /*
  * 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)
 {
@@ -520,6 +519,39 @@
 	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);
@@ -329,7 +329,7 @@
 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
@@ -245,7 +245,8 @@
 #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
@@ -58,8 +58,6 @@
 /* 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  */
@@ -92,11 +90,6 @@
 	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)
@@ -105,5 +98,12 @@
 	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 */
...	...	@@ -651,6 +651,7 @@
651	651	* Specifically, in the case of x86, we will always add
652	652	* memory to the highmem for now.
653	653	*/
	654	+#ifdef CONFIG_HOTPLUG_MEMORY
654	655	#ifndef CONFIG_NEED_MULTIPLE_NODES
655	656	int add_memory(u64 start, u64 size)
656	657	{
...	...	@@ -666,6 +667,7 @@
666	667	{
667	668	return -EINVAL;
668	669	}
	670	+#endif
669	671	#endif
670	672
671	673	kmem_cache_t *pgd_cache;
...	...	@@ -80,7 +80,7 @@
80	80	return 0;
81	81	}
82	82
83		-int __init e820_mapped(unsigned long start, unsigned long end, unsigned type)
	83	+int __meminit e820_mapped(unsigned long start, unsigned long end, unsigned type)
84	84	{
85	85	int i;
86	86	for (i = 0; i < e820.nr_map; i++) {
...	...	@@ -507,9 +507,8 @@
507	507
508	508	/*
509	509	* Memory hotplug specific functions
510		- * These are only for non-NUMA machines right now.
511	510	*/
512		-#ifdef CONFIG_MEMORY_HOTPLUG
	511	+#if defined(CONFIG_ACPI_HOTPLUG_MEMORY) \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
513	512
514	513	void online_page(struct page *page)
515	514	{
...	...	@@ -520,6 +519,39 @@
520	519	num_physpages++;
521	520	}
522	521
	522	+#ifndef CONFIG_MEMORY_HOTPLUG
	523	+/*
	524	+ * Memory Hotadd without sparsemem. The mem_maps have been allocated in advance,
	525	+ * just online the pages.
	526	+ */
	527	+int __add_pages(struct zone *z, unsigned long start_pfn, unsigned long nr_pages)
	528	+{
	529	+ int err = -EIO;
	530	+ unsigned long pfn;
	531	+ unsigned long total = 0, mem = 0;
	532	+ for (pfn = start_pfn; pfn < start_pfn + nr_pages; pfn++) {
	533	+ unsigned long addr = pfn << PAGE_SHIFT;
	534	+ if (pfn_valid(pfn) && e820_mapped(addr, addr+1, E820_RAM)) {
	535	+ online_page(pfn_to_page(pfn));
	536	+ err = 0;
	537	+ mem++;
	538	+ }
	539	+ total++;
	540	+ }
	541	+ if (!err) {
	542	+ z->spanned_pages += total;
	543	+ z->present_pages += mem;
	544	+ z->zone_pgdat->node_spanned_pages += total;
	545	+ z->zone_pgdat->node_present_pages += mem;
	546	+ }
	547	+ return err;
	548	+}
	549	+#endif
	550	+
	551	+/*
	552	+ * Memory is added always to NORMAL zone. This means you will never get
	553	+ * additional DMA/DMA32 memory.
	554	+ */
523	555	int add_memory(u64 start, u64 size)
524	556	{
525	557	struct pglist_data *pgdat = NODE_DATA(0);
...	...	@@ -329,7 +329,7 @@
329	329	config ACPI_HOTPLUG_MEMORY
330	330	tristate "Memory Hotplug"
331	331	depends on ACPI
332		- depends on MEMORY_HOTPLUG
	332	+ depends on MEMORY_HOTPLUG \|\| X86_64
333	333	default n
334	334	help
335	335	This driver adds supports for ACPI Memory Hotplug. This driver
...	...	@@ -245,7 +245,8 @@
245	245	#define __cpuexitdata __exitdata
246	246	#endif
247	247
248		-#ifdef CONFIG_MEMORY_HOTPLUG
	248	+#if defined(CONFIG_MEMORY_HOTPLUG) \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
	249	+ \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
249	250	#define __meminit
250	251	#define __meminitdata
251	252	#define __memexit
...	...	@@ -58,8 +58,6 @@
58	58	/* need some defines for these for archs that don't support it */
59	59	extern void online_page(struct page *page);
60	60	/* VM interface that may be used by firmware interface */
61		-extern int add_memory(u64 start, u64 size);
62		-extern int remove_memory(u64 start, u64 size);
63	61	extern int online_pages(unsigned long, unsigned long);
64	62
65	63	/* reasonably generic interface to expand the physical pages in a zone */
...	...	@@ -92,11 +90,6 @@
92	90	return -ENOSYS;
93	91	}
94	92
95		-static inline int __add_pages(struct zone *zone, unsigned long start_pfn,
96		- unsigned long nr_pages)
97		-{
98		- return mhp_notimplemented(__FUNCTION__);
99		-}
100	93	#endif /* ! CONFIG_MEMORY_HOTPLUG */
101	94	static inline int __remove_pages(struct zone *zone, unsigned long start_pfn,
102	95	unsigned long nr_pages)
...	...	@@ -105,5 +98,12 @@
105	98	dump_stack();
106	99	return -ENOSYS;
107	100	}
	101	+
	102	+#if defined(CONFIG_MEMORY_HOTPLUG) \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
	103	+ \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
	104	+extern int add_memory(u64 start, u64 size);
	105	+extern int remove_memory(u64 start, u64 size);
	106	+#endif
	107	+
108	108	#endif /* __LINUX_MEMORY_HOTPLUG_H */