[PATCH 3/10] memory-hotplug : introduce new function arch_remove_memory() for removing page table depends on architecture
From: Yasuaki Ishimatsu <hidden>
Date: 2012-10-05 02:30:18
Also in:
linux-acpi, linux-mm, linux-s390, linux-sh, lkml, sparclinux
From: Wen Congyang <redacted>
For removing memory, we need to remove page table. But it depends
on architecture. So the patch introduce arch_remove_memory() for
removing page table. Now it only calls __remove_pages().
Note: __remove_pages() for some archtecuture is not implemented
(I don't know how to implement it for s390).
CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <redacted>
CC: Len Brown <redacted>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <redacted>
CC: Christoph Lameter <redacted>
Cc: Minchan Kim <redacted>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <redacted>
CC: Yasuaki Ishimatsu <redacted>
Signed-off-by: Wen Congyang <redacted>
---
arch/ia64/mm/init.c | 18 ++++++++++++++++++
arch/powerpc/mm/mem.c | 12 ++++++++++++
arch/s390/mm/init.c | 12 ++++++++++++
arch/sh/mm/init.c | 17 +++++++++++++++++
arch/tile/mm/init.c | 8 ++++++++
arch/x86/mm/init_32.c | 12 ++++++++++++
arch/x86/mm/init_64.c | 15 +++++++++++++++
include/linux/memory_hotplug.h | 1 +
mm/memory_hotplug.c | 1 +
9 files changed, 96 insertions(+)
Index: linux-3.6/arch/ia64/mm/init.c
===================================================================--- linux-3.6.orig/arch/ia64/mm/init.c 2012-10-04 18:27:03.082498276 +0900
+++ linux-3.6/arch/ia64/mm/init.c 2012-10-04 18:28:50.087606867 +0900@@ -688,6 +688,24 @@ int arch_add_memory(int nid, u64 start, return ret; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + int ret; + + zone = page_zone(pfn_to_page(start_pfn)); + ret = __remove_pages(zone, start_pfn, nr_pages); + if (ret) + pr_warn("%s: Problem encountered in __remove_pages() as" + " ret=%d\n", __func__, ret); + + return ret; +} +#endif #endif /*
Index: linux-3.6/arch/powerpc/mm/mem.c ===================================================================
--- linux-3.6.orig/arch/powerpc/mm/mem.c 2012-10-04 18:27:03.084498278 +0900
+++ linux-3.6/arch/powerpc/mm/mem.c 2012-10-04 18:28:50.094606874 +0900@@ -133,6 +133,18 @@ int arch_add_memory(int nid, u64 start, return __add_pages(nid, zone, start_pfn, nr_pages); } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + + zone = page_zone(pfn_to_page(start_pfn)); + return __remove_pages(zone, start_pfn, nr_pages); +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ /*
Index: linux-3.6/arch/s390/mm/init.c ===================================================================
--- linux-3.6.orig/arch/s390/mm/init.c 2012-10-04 18:27:03.080498274 +0900
+++ linux-3.6/arch/s390/mm/init.c 2012-10-04 18:28:50.104606884 +0900@@ -257,4 +257,16 @@ int arch_add_memory(int nid, u64 start, vmem_remove_mapping(start, size); return rc; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + /* + * There is no hardware or firmware interface which could trigger a + * hot memory remove on s390. So there is nothing that needs to be + * implemented. + */ + return -EBUSY; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */
Index: linux-3.6/arch/sh/mm/init.c ===================================================================
--- linux-3.6.orig/arch/sh/mm/init.c 2012-10-04 18:27:03.091498285 +0900
+++ linux-3.6/arch/sh/mm/init.c 2012-10-04 18:28:50.116606897 +0900@@ -558,4 +558,21 @@ int memory_add_physaddr_to_nid(u64 addr) EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + int ret; + + zone = page_zone(pfn_to_page(start_pfn)); + ret = __remove_pages(zone, start_pfn, nr_pages); + if (unlikely(ret)) + pr_warn("%s: Failed, __remove_pages() == %d\n", __func__, + ret); + + return ret; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */
Index: linux-3.6/arch/tile/mm/init.c ===================================================================
--- linux-3.6.orig/arch/tile/mm/init.c 2012-10-04 18:27:03.078498272 +0900
+++ linux-3.6/arch/tile/mm/init.c 2012-10-04 18:28:50.122606903 +0900@@ -935,6 +935,14 @@ int remove_memory(u64 start, u64 size) { return -EINVAL; } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + /* TODO */ + return -EBUSY; +} +#endif #endif struct kmem_cache *pgd_cache;
Index: linux-3.6/arch/x86/mm/init_32.c ===================================================================
--- linux-3.6.orig/arch/x86/mm/init_32.c 2012-10-04 18:27:03.089498283 +0900
+++ linux-3.6/arch/x86/mm/init_32.c 2012-10-04 18:28:50.128606909 +0900@@ -842,6 +842,18 @@ int arch_add_memory(int nid, u64 start, return __add_pages(nid, zone, start_pfn, nr_pages); } + +#ifdef CONFIG_MEMORY_HOTREMOVE +int arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + + zone = page_zone(pfn_to_page(start_pfn)); + return __remove_pages(zone, start_pfn, nr_pages); +} +#endif #endif /*
Index: linux-3.6/arch/x86/mm/init_64.c ===================================================================
--- linux-3.6.orig/arch/x86/mm/init_64.c 2012-10-04 18:27:03.086498280 +0900
+++ linux-3.6/arch/x86/mm/init_64.c 2012-10-04 18:28:50.132606913 +0900@@ -675,6 +675,21 @@ int arch_add_memory(int nid, u64 start, } EXPORT_SYMBOL_GPL(arch_add_memory); +#ifdef CONFIG_MEMORY_HOTREMOVE +int __ref arch_remove_memory(u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + int ret; + + zone = page_zone(pfn_to_page(start_pfn)); + ret = __remove_pages(zone, start_pfn, nr_pages); + WARN_ON_ONCE(ret); + + return ret; +} +#endif #endif /* CONFIG_MEMORY_HOTPLUG */ static struct kcore_list kcore_vsyscall;
Index: linux-3.6/include/linux/memory_hotplug.h ===================================================================
--- linux-3.6.orig/include/linux/memory_hotplug.h 2012-10-04 18:27:03.094498288 +0900
+++ linux-3.6/include/linux/memory_hotplug.h 2012-10-04 18:28:50.137606918 +0900@@ -85,6 +85,7 @@ extern void __online_page_free(struct pa #ifdef CONFIG_MEMORY_HOTREMOVE extern bool is_pageblock_removable_nolock(struct page *page); +extern int arch_remove_memory(u64 start, u64 size); #endif /* CONFIG_MEMORY_HOTREMOVE */ /* reasonably generic interface to expand the physical pages in a zone */
Index: linux-3.6/mm/memory_hotplug.c ===================================================================
--- linux-3.6.orig/mm/memory_hotplug.c 2012-10-04 18:28:42.851599524 +0900
+++ linux-3.6/mm/memory_hotplug.c 2012-10-04 18:29:50.577668254 +0900@@ -1062,6 +1062,7 @@ int __ref remove_memory(int nid, u64 sta /* remove memmap entry */ firmware_map_remove(start, start + size, "System RAM"); + arch_remove_memory(start, size); out: unlock_memory_hotplug(); return ret;