From 4edd7ceff0662afde195da6f6c43e7cbe1ed2dc4 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Mon, 29 Apr 2013 15:08:22 -0700 Subject: [PATCH] mm, hotplug: avoid compiling memory hotremove functions when disabled __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 Acked-by: Toshi Kani Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Greg Kroah-Hartman Cc: Wen Congyang Cc: Tang Chen Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../platforms/pseries/hotplug-memory.c | 12 ++++ drivers/base/memory.c | 44 ++++++------ include/linux/memory.h | 3 +- include/linux/memory_hotplug.h | 4 +- mm/memory_hotplug.c | 68 +++++++++--------- mm/sparse.c | 72 ++++++++++--------- 6 files changed, 113 insertions(+), 90 deletions(-) diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index 2372c609fa2b..9a432de363b8 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -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) { diff --git a/drivers/base/memory.c b/drivers/base/memory.c index a51007b79032..65d9799cbb61 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -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. diff --git a/include/linux/memory.h b/include/linux/memory.h index 0ff6598ee62f..73817af8b480 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -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 *, diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index b6a3be7d47bf..3e622c610925 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -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); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c916582591eb..60f6daad1076 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -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) { diff --git a/mm/sparse.c b/mm/sparse.c index a37be5f9050d..1c91f0d3f6ab 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -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 */ -- 2.30.2