At 07/20/2012 04:21 PM, Yasuaki Ishimatsu Wrote:
> 2012/07/20 16:12, Wen Congyang wrote:
>> We don't call __add_pages() directly in the function add_memory()
>> because some other architecture related thins needs to be done
>> before or after calling __add_pages(). So we should not call
>> __remove_pages() directly in the function remove_memory.
>> Introduce new function arch_remove_memory() to revert the things done
>> in arch_add_memory().
>>
>> Note: the function for x86_64 will be implemented later. And I don't
>> know how to implement it for s390.
>
> I think you need cc to other arch ML for reviewing the patch.
I forgot to do it.
>
>
>> CC: David Rientjes <rientjes@xxxxxxxxxx>
>> CC: Jiang Liu <liuj97@xxxxxxxxx>
>> CC: Len Brown <len.brown@xxxxxxxxx>
>> CC: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
>> CC: Paul Mackerras <paulus@xxxxxxxxx>
>> CC: Christoph Lameter <cl@xxxxxxxxx>
>> Cc: Minchan Kim <minchan.kim@xxxxxxxxx>
>> CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>> CC: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
>> CC: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx>
>> Signed-off-by: Wen Congyang <wency@xxxxxxxxxxxxxx>
>> ---
>> arch/ia64/mm/init.c | 16 ++++++++++++++++
>> arch/powerpc/mm/mem.c | 14 ++++++++++++++
>> arch/s390/mm/init.c | 8 ++++++++
>> arch/sh/mm/init.c | 15 +++++++++++++++
>> arch/tile/mm/init.c | 8 ++++++++
>> arch/x86/mm/init_32.c | 10 ++++++++++
>> arch/x86/mm/init_64.c | 7 +++++++
>> include/linux/memory_hotplug.h | 1 +
>> mm/memory_hotplug.c | 2 +-
>> 9 files changed, 80 insertions(+), 1 deletions(-)
>>
>> diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
>> index 0eab454..1e345ed 100644
>> --- a/arch/ia64/mm/init.c
>> +++ b/arch/ia64/mm/init.c
>> @@ -688,6 +688,22 @@ int arch_add_memory(int nid, u64 start, u64 size)
>>
>> 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;
>> + int ret;
>> +
>> + ret = __remove_pages(start_pfn, nr_pages);
>> + if (ret)
>> + pr_warn("%s: Problem encountered in __remove_pages() as"
>> + " ret=%d\n", __func__, ret);
>> +
>> + return ret;
>> +}
>> +#endif
>> #endif
>>
>> /*
>> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
>> index baaafde..249cef4 100644
>> --- a/arch/powerpc/mm/mem.c
>> +++ b/arch/powerpc/mm/mem.c
>> @@ -133,6 +133,20 @@ int arch_add_memory(int nid, u64 start, u64 size)
>>
>> 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;
>> +
>> + start = (unsigned long)__va(start);
>> + if (remove_section_mapping(start, start + size))
>> + return -EINVAL;
>> +
>> + return __remove_pages(start_pfn, nr_pages);
>> +}
>> +#endif
>> #endif /* CONFIG_MEMORY_HOTPLUG */
>>
>> /*
>> diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
>> index 2bea060..3de0d5b 100644
>> --- a/arch/s390/mm/init.c
>> +++ b/arch/s390/mm/init.c
>> @@ -259,4 +259,12 @@ int arch_add_memory(int nid, u64 start, u64 size)
>> vmem_remove_mapping(start, size);
>> return rc;
>> }
>> +
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +int arch_remove_memory(u64 start, u64 size)
>> +{
>> + /* TODO */
>> + return -EBUSY;
>> +}
>> +#endif
>> #endif /* CONFIG_MEMORY_HOTPLUG */
>> diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
>> index 82cc576..fc84491 100644
>> --- a/arch/sh/mm/init.c
>> +++ b/arch/sh/mm/init.c
>> @@ -558,4 +558,19 @@ 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;
>> + int ret;
>> +
>> + ret = __remove_pages(start_pfn, nr_pages);
>> + if (unlikely(ret))
>> + pr_warn("%s: Failed, __remove_pages() == %d\n", __func__,
>> + ret);
>> +
>> + return ret;
>> +}
>> +#endif
>> #endif /* CONFIG_MEMORY_HOTPLUG */
>> diff --git a/arch/tile/mm/init.c b/arch/tile/mm/init.c
>> index 630dd2c..bdd8a99 100644
>> --- a/arch/tile/mm/init.c
>> +++ b/arch/tile/mm/init.c
>> @@ -947,6 +947,14 @@ 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;
>> diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
>> index 575d86f..a690153 100644
>> --- a/arch/x86/mm/init_32.c
>> +++ b/arch/x86/mm/init_32.c
>> @@ -842,6 +842,16 @@ int arch_add_memory(int nid, u64 start, u64 size)
>>
>> return __add_pages(nid, zone, start_pfn, nr_pages);
>> }
>> +
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +int arch_remove_memory(unsigned long start, unsigned long size)
>> +{
>> + unsigned long start_pfn = start >> PAGE_SHIFT;
>> + unsigned long nr_pages = size >> PAGE_SHIFT;
>> +
>> + return __remove_pages(start_pfn, nr_pages);
>> +}
>> +#endif
>> #endif
>>
>> /*
>> diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
>> index 9e635b3..78b94bc 100644
>> --- a/arch/x86/mm/init_64.c
>> +++ b/arch/x86/mm/init_64.c
>> @@ -675,6 +675,13 @@ int arch_add_memory(int nid, u64 start, u64 size)
>> }
>> EXPORT_SYMBOL_GPL(arch_add_memory);
>>
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +int arch_remove_memory(unsigned long start, unsigned long size)
>> +{
>> + /* TODO */
>> + return -EBUSY;
>> +}
>> +#endif
>
> Why does not the function call __remove_pages()?
arch_remove_memory() should clear the page table after remove pages here.
I implement this function in patch 8.
Thanks
Wen Congyang
>
> Thanks,
> Yasuaki ishimatsu
>
>> #endif /* CONFIG_MEMORY_HOTPLUG */
>>
>> static struct kcore_list kcore_vsyscall;
>> diff --git a/include/linux/memory_hotplug.h
>> b/include/linux/memory_hotplug.h
>> index 2ba0a1a..8639799 100644
>> --- a/include/linux/memory_hotplug.h
>> +++ b/include/linux/memory_hotplug.h
>> @@ -84,6 +84,7 @@ 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(unsigned long start, unsigned long size);
>> #endif /* CONFIG_MEMORY_HOTREMOVE */
>>
>> /* reasonably generic interface to expand the physical pages in a
>> zone */
>> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
>> index dccdf71..cc2c8b9 100644
>> --- a/mm/memory_hotplug.c
>> +++ b/mm/memory_hotplug.c
>> @@ -1055,7 +1055,7 @@ int __ref remove_memory(int nid, u64 start, u64
>> size)
>> unregister_one_node(nid);
>> }
>>
>> - __remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT);
>> + arch_remove_memory(start, size);
>> out:
>> unlock_memory_hotplug();
>> return ret;
>>
>
>
>
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