At 07/18/2012 06:06 PM, Yasuaki Ishimatsu Wrote:
> acpi_memory_device_remove() has been prepared to remove physical memory.
> But, the function only frees acpi_memory_device currentlry. 
> 
> The patch adds following functions into acpi_memory_device_remove():
>   - offline memory
>   - remove physical memory. It only check whether memory is online or not.
>   - free acpi_memory_device
> 
> CC: David Rientjes <rient...@google.com>
> CC: Jiang Liu <liu...@gmail.com>
> CC: Len Brown <len.br...@intel.com>
> CC: Benjamin Herrenschmidt <b...@kernel.crashing.org>
> CC: Paul Mackerras <pau...@samba.org> 
> CC: Christoph Lameter <c...@linux.com>
> Cc: Minchan Kim <minchan....@gmail.com>
> CC: Andrew Morton <a...@linux-foundation.org>
> CC: KOSAKI Motohiro <kosaki.motoh...@jp.fujitsu.com> 
> CC: Wen Congyang <we...@cn.fujitsu.com>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com>
> 
> ---
>  drivers/acpi/acpi_memhotplug.c |   27 ++++++++++++++++++++++++++-
>  drivers/base/memory.c          |   39 +++++++++++++++++++++++++++++++++++++++
>  include/linux/memory.h         |    5 +++++
>  include/linux/memory_hotplug.h |    5 +++++
>  mm/memory_hotplug.c            |   22 ++++++++++++++++++++++
>  5 files changed, 97 insertions(+), 1 deletion(-)
> 
> Index: linux-3.5-rc6/drivers/acpi/acpi_memhotplug.c
> ===================================================================
> --- linux-3.5-rc6.orig/drivers/acpi/acpi_memhotplug.c 2012-07-17 
> 11:20:15.117796971 +0900
> +++ linux-3.5-rc6/drivers/acpi/acpi_memhotplug.c      2012-07-17 
> 13:36:30.325594022 +0900
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/types.h>
> +#include <linux/memory.h>
>  #include <linux/memory_hotplug.h>
>  #include <linux/slab.h>
>  #include <acpi/acpi_drivers.h>
> @@ -452,12 +453,36 @@ static int acpi_memory_device_add(struct
>  static int acpi_memory_device_remove(struct acpi_device *device, int type)
>  {
>       struct acpi_memory_device *mem_device = NULL;
> -
> +     struct acpi_memory_info *info, *tmp;
> +     int result;
> +     int node;
>  
>       if (!device || !acpi_driver_data(device))
>               return -EINVAL;
>  
>       mem_device = acpi_driver_data(device);
> +
> +     node = acpi_get_node(mem_device->device->handle);
> +     list_for_each_entry_safe(info, tmp, &mem_device->res_list, list) {
> +             if (!info->enabled)
> +                     continue;
> +
> +             if (!is_memblk_offline(info->start_addr, info->length)) {
> +                     result = offline_memory(info->start_addr, info->length);
> +                     if (result)
> +                             return result;
> +             }
> +             if (node < 0)
> +                     node = memory_add_physaddr_to_nid(info->start_addr);
> +
> +             result = remove_memory(node, info->start_addr, info->length);
> +             if (result)
> +                     return result;
> +
> +             list_del(&info->list);
> +             kfree(info);
> +     }
> +
>       kfree(mem_device);
>  
>       return 0;
> Index: linux-3.5-rc6/include/linux/memory_hotplug.h
> ===================================================================
> --- linux-3.5-rc6.orig/include/linux/memory_hotplug.h 2012-07-17 
> 11:20:15.133796772 +0900
> +++ linux-3.5-rc6/include/linux/memory_hotplug.h      2012-07-17 
> 11:29:41.490716352 +0900
> @@ -221,6 +221,7 @@ static inline void unlock_memory_hotplug
>  #ifdef CONFIG_MEMORY_HOTREMOVE
>  
>  extern int is_mem_section_removable(unsigned long pfn, unsigned long 
> nr_pages);
> +extern int remove_memory(int nid, u64 start, u64 size);
>  
>  #else
>  static inline int is_mem_section_removable(unsigned long pfn,
> @@ -228,6 +229,10 @@ static inline int is_mem_section_removab
>  {
>       return 0;
>  }
> +static inline int remove_memory(int nid, u64 start, u64 size)
> +{
> +     return -EBUSY;
> +}
>  #endif /* CONFIG_MEMORY_HOTREMOVE */
>  
>  extern int mem_online_node(int nid);
> Index: linux-3.5-rc6/mm/memory_hotplug.c
> ===================================================================
> --- linux-3.5-rc6.orig/mm/memory_hotplug.c    2012-07-17 11:20:15.129796821 
> +0900
> +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-17 13:25:18.952986069 +0900
> @@ -998,6 +998,28 @@ int offline_memory(u64 start, u64 size)
>       end_pfn = start_pfn + PFN_DOWN(size);
>       return offline_pages(start_pfn, end_pfn, 120 * HZ);
>  }
> +
> +int remove_memory(int nid, u64 start, u64 size)
> +{
> +     int ret = -EBUSY;
> +     lock_memory_hotplug();
> +     /*
> +      * The memory might become online by other task, even if you offine it.
> +      * So we check whether the cpu has been onlined or not.
> +      */
> +     if (!is_memblk_offline(start, size)) {
> +             pr_warn("memory removing [mem %#010llx-%#010llx] failed, "
> +                     "because the memmory range is online\n",
> +                     start, start + size);
> +             ret = -EAGAIN;
> +     }
> +
> +     unlock_memory_hotplug();
> +     return ret;
> +
> +}
> +EXPORT_SYMBOL_GPL(remove_memory);
> +
>  #else
>  int offline_memory(u64 start, u64 size)
>  {
> Index: linux-3.5-rc6/drivers/base/memory.c
> ===================================================================
> --- linux-3.5-rc6.orig/drivers/base/memory.c  2012-07-17 11:20:15.120796934 
> +0900
> +++ linux-3.5-rc6/drivers/base/memory.c       2012-07-17 11:20:54.626302995 
> +0900
> @@ -70,6 +70,45 @@ void unregister_memory_isolate_notifier(
>  }
>  EXPORT_SYMBOL(unregister_memory_isolate_notifier);
>  
> +bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +     struct memory_block *mem = NULL;
> +     struct mem_section *section;
> +     unsigned long start_pfn, end_pfn;
> +     unsigned long pfn, section_nr;
> +
> +     start_pfn = PFN_DOWN(start);
> +     end_pfn = start_pfn + PFN_DOWN(start);

This line is wrong. I think you want this:
end_pfn = start_pfn + PFN_UP(size);

> +
> +     for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
> +             section_nr = pfn_to_section_nr(pfn);
> +             if (!present_section_nr(section_nr));

The ';' should be removed. Otherwise, this function always return true...

Thanks
Wen Congyang

> +                     continue;
> +
> +             section = __nr_to_section(section_nr);
> +             /* same memblock? */
> +             if (mem)
> +                     if((section_nr >= mem->start_section_nr) &&
> +                        (section_nr <= mem->end_section_nr))
> +                             continue;
> +
> +             mem = find_memory_block_hinted(section, mem);
> +             if (!mem)
> +                     continue;
> +             if (mem->state == MEM_OFFLINE)
> +                     continue;
> +
> +             kobject_put(&mem->dev.kobj);
> +             return false;
> +     }
> +
> +     if (mem)
> +             kobject_put(&mem->dev.kobj);
> +
> +     return true;
> +}
> +EXPORT_SYMBOL(is_memblk_offline);
> +
>  /*
>   * register_memory - Setup a sysfs device for a memory block
>   */
> Index: linux-3.5-rc6/include/linux/memory.h
> ===================================================================
> --- linux-3.5-rc6.orig/include/linux/memory.h 2012-07-17 11:18:00.693477455 
> +0900
> +++ linux-3.5-rc6/include/linux/memory.h      2012-07-17 11:20:54.632302919 
> +0900
> @@ -106,6 +106,10 @@ static inline int memory_isolate_notify(
>  {
>       return 0;
>  }
> +static inline bool is_memblk_offline(unsigned long start, unsigned long size)
> +{
> +     return false;
> +}
>  #else
>  extern int register_memory_notifier(struct notifier_block *nb);
>  extern void unregister_memory_notifier(struct notifier_block *nb);
> @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne
>  extern struct memory_block *find_memory_block_hinted(struct mem_section *,
>                                                       struct memory_block *);
>  extern struct memory_block *find_memory_block(struct mem_section *);
> +extern bool is_memblk_offline(unsigned long start, unsigned long size);
>  #define CONFIG_MEM_BLOCK_SIZE        (PAGES_PER_SECTION<<PAGE_SHIFT)
>  enum mem_add_context { BOOT, HOTPLUG };
>  #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
> 
> 

_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev

Reply via email to