Re: [RFC PATCH v4 1/13] memory-hotplug : rename remove_memory tooffline_memory

From: Yasuaki Ishimatsu
Date: Thu Jul 19 2012 - 05:27:00 EST


Hi Bob,

2012/07/19 17:19, Bob Liu wrote:
Hi Yasuaki,

On Wed, Jul 18, 2012 at 6:05 PM, Yasuaki Ishimatsu
<isimatu.yasuaki@xxxxxxxxxxxxxx> wrote:
remove_memory() does not remove memory but just offlines memory. The patch
changes name of it to offline_memory().

Since offline_memory() just align the start/end pfn and there is no
matched online_memory() function,
i think it's better to remove this function and add the alignment into
offline_pages().

If we change it, these argument becomes different as follows:

online_pages : page frame number and number of page frame number
offline_pages : memory address and memory length

I think it is ugly. So I don't want to change it. As you say, there is no
function that matches to offline_memory(). If we create export symbol
function for onlining page, in this case, the function should be named
online_memory().

Thanks,
Yasuaki Ishimatsu



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: Wen Congyang <wency@xxxxxxxxxxxxxx>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx>

---
drivers/acpi/acpi_memhotplug.c | 2 +-
drivers/base/memory.c | 4 ++--
include/linux/memory_hotplug.h | 2 +-
mm/memory_hotplug.c | 6 +++---
4 files changed, 7 insertions(+), 7 deletions(-)

Index: linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-3.5-rc4.orig/drivers/acpi/acpi_memhotplug.c 2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/drivers/acpi/acpi_memhotplug.c 2012-07-03 14:21:49.458374960 +0900
@@ -318,7 +318,7 @@ static int acpi_memory_disable_device(st
*/
list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
if (info->enabled) {
- result = remove_memory(info->start_addr, info->length);
+ result = offline_memory(info->start_addr, info->length);
if (result)
return result;
}
Index: linux-3.5-rc4/drivers/base/memory.c
===================================================================
--- linux-3.5-rc4.orig/drivers/base/memory.c 2012-07-03 14:21:46.095417003 +0900
+++ linux-3.5-rc4/drivers/base/memory.c 2012-07-03 14:21:49.459374948 +0900
@@ -266,8 +266,8 @@ memory_block_action(unsigned long phys_i
break;
case MEM_OFFLINE:
start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
- ret = remove_memory(start_paddr,
- nr_pages << PAGE_SHIFT);
+ ret = offline_memory(start_paddr,
+ nr_pages << PAGE_SHIFT);
break;
default:
WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
Index: linux-3.5-rc4/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc4.orig/mm/memory_hotplug.c 2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/mm/memory_hotplug.c 2012-07-03 14:21:49.466374860 +0900
@@ -990,7 +990,7 @@ out:
return ret;
}

-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
{
unsigned long start_pfn, end_pfn;

@@ -999,9 +999,9 @@ int remove_memory(u64 start, u64 size)
return offline_pages(start_pfn, end_pfn, 120 * HZ);
}
#else
-int remove_memory(u64 start, u64 size)
+int offline_memory(u64 start, u64 size)
{
return -EINVAL;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
-EXPORT_SYMBOL_GPL(remove_memory);
+EXPORT_SYMBOL_GPL(offline_memory);
Index: linux-3.5-rc4/include/linux/memory_hotplug.h
===================================================================
--- linux-3.5-rc4.orig/include/linux/memory_hotplug.h 2012-07-03 14:21:46.102416917 +0900
+++ linux-3.5-rc4/include/linux/memory_hotplug.h 2012-07-03 14:21:49.471374796 +0900
@@ -233,7 +233,7 @@ static inline int is_mem_section_removab
extern int mem_online_node(int nid);
extern int add_memory(int nid, u64 start, u64 size);
extern int arch_add_memory(int nid, u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
+extern int offline_memory(u64 start, u64 size);
extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
int nr_pages);
extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);

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