summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorZhang Zhen <zhenzhang.zhang@huawei.com>2014-10-09 15:26:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 22:25:52 -0400
commited2f240094f900833ac06f533ab8bbcf0a1e8199 (patch)
treea29d18bd9463645fa6ecdab3dd90945f861097d2
parentcc71aba348906ff93a4ad2f600045ee2d1ecc291 (diff)
memory-hotplug: add sysfs valid_zones attribute
Currently memory-hotplug has two limits: 1. If the memory block is in ZONE_NORMAL, you can change it to ZONE_MOVABLE, but this memory block must be adjacent to ZONE_MOVABLE. 2. If the memory block is in ZONE_MOVABLE, you can change it to ZONE_NORMAL, but this memory block must be adjacent to ZONE_NORMAL. With this patch, we can easy to know a memory block can be onlined to which zone, and don't need to know the above two limits. Updated the related Documentation. [akpm@linux-foundation.org: use conventional comment layout] [akpm@linux-foundation.org: fix build with CONFIG_MEMORY_HOTREMOVE=n] [akpm@linux-foundation.org: remove unused local zone_prev] Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--Documentation/ABI/testing/sysfs-devices-memory8
-rw-r--r--Documentation/memory-hotplug.txt11
-rw-r--r--drivers/base/memory.c42
-rw-r--r--include/linux/memory_hotplug.h1
-rw-r--r--mm/memory_hotplug.c2
5 files changed, 62 insertions, 2 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-memory b/Documentation/ABI/testing/sysfs-devices-memory
index 7405de26ee60..deef3b5723cf 100644
--- a/Documentation/ABI/testing/sysfs-devices-memory
+++ b/Documentation/ABI/testing/sysfs-devices-memory
@@ -61,6 +61,14 @@ Users: hotplug memory remove tools
http://www.ibm.com/developerworks/wikis/display/LinuxP/powerpc-utils
+What: /sys/devices/system/memory/memoryX/valid_zones
+Date: July 2014
+Contact: Zhang Zhen <zhenzhang.zhang@huawei.com>
+Description:
+ The file /sys/devices/system/memory/memoryX/valid_zones is
+ read-only and is designed to show which zone this memory
+ block can be onlined to.
+
What: /sys/devices/system/memoryX/nodeY
Date: October 2009
Contact: Linux Memory Management list <linux-mm@kvack.org>
diff --git a/Documentation/memory-hotplug.txt b/Documentation/memory-hotplug.txt
index 45134dc23854..ea03abfc97e9 100644
--- a/Documentation/memory-hotplug.txt
+++ b/Documentation/memory-hotplug.txt
@@ -155,6 +155,7 @@ Under each memory block, you can see 4 files:
/sys/devices/system/memory/memoryXXX/phys_device
/sys/devices/system/memory/memoryXXX/state
/sys/devices/system/memory/memoryXXX/removable
+/sys/devices/system/memory/memoryXXX/valid_zones
'phys_index' : read-only and contains memory block id, same as XXX.
'state' : read-write
@@ -170,6 +171,15 @@ Under each memory block, you can see 4 files:
block is removable and a value of 0 indicates that
it is not removable. A memory block is removable only if
every section in the block is removable.
+'valid_zones' : read-only: designed to show which zones this memory block
+ can be onlined to.
+ The first column shows it's default zone.
+ "memory6/valid_zones: Normal Movable" shows this memoryblock
+ can be onlined to ZONE_NORMAL by default and to ZONE_MOVABLE
+ by online_movable.
+ "memory7/valid_zones: Movable Normal" shows this memoryblock
+ can be onlined to ZONE_MOVABLE by default and to ZONE_NORMAL
+ by online_kernel.
NOTE:
These directories/files appear after physical memory hotplug phase.
@@ -408,7 +418,6 @@ node if necessary.
- allowing memory hot-add to ZONE_MOVABLE. maybe we need some switch like
sysctl or new control file.
- showing memory block and physical device relationship.
- - showing memory block is under ZONE_MOVABLE or not
- test and make it better memory offlining.
- support HugeTLB page migration and offlining.
- memmap removing at memory offline.
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index a2e13e250bba..7c5d87191b28 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -373,6 +373,45 @@ static ssize_t show_phys_device(struct device *dev,
return sprintf(buf, "%d\n", mem->phys_device);
}
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static ssize_t show_valid_zones(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct memory_block *mem = to_memory_block(dev);
+ unsigned long start_pfn, end_pfn;
+ unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
+ struct page *first_page;
+ struct zone *zone;
+
+ start_pfn = section_nr_to_pfn(mem->start_section_nr);
+ end_pfn = start_pfn + nr_pages;
+ first_page = pfn_to_page(start_pfn);
+
+ /* The block contains more than one zone can not be offlined. */
+ if (!test_pages_in_a_zone(start_pfn, end_pfn))
+ return sprintf(buf, "none\n");
+
+ zone = page_zone(first_page);
+
+ if (zone_idx(zone) == ZONE_MOVABLE - 1) {
+ /*The mem block is the last memoryblock of this zone.*/
+ if (end_pfn == zone_end_pfn(zone))
+ return sprintf(buf, "%s %s\n",
+ zone->name, (zone + 1)->name);
+ }
+
+ if (zone_idx(zone) == ZONE_MOVABLE) {
+ /*The mem block is the first memoryblock of ZONE_MOVABLE.*/
+ if (start_pfn == zone->zone_start_pfn)
+ return sprintf(buf, "%s %s\n",
+ zone->name, (zone - 1)->name);
+ }
+
+ return sprintf(buf, "%s\n", zone->name);
+}
+static DEVICE_ATTR(valid_zones, 0444, show_valid_zones, NULL);
+#endif
+
static DEVICE_ATTR(phys_index, 0444, show_mem_start_phys_index, NULL);
static DEVICE_ATTR(state, 0644, show_mem_state, store_mem_state);
static DEVICE_ATTR(phys_device, 0444, show_phys_device, NULL);
@@ -523,6 +562,9 @@ static struct attribute *memory_memblk_attrs[] = {
&dev_attr_state.attr,
&dev_attr_phys_device.attr,
&dev_attr_removable.attr,
+#ifdef CONFIG_MEMORY_HOTREMOVE
+ &dev_attr_valid_zones.attr,
+#endif
NULL
};
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index d9524c49d767..8f1a41951df9 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -84,6 +84,7 @@ extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
/* VM interface that may be used by firmware interface */
extern int online_pages(unsigned long, unsigned long, int);
+extern int test_pages_in_a_zone(unsigned long, unsigned long);
extern void __offline_isolated_pages(unsigned long, unsigned long);
typedef void (*online_page_callback_t)(struct page *page);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 2ff8c2325e96..29d8693d0c61 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1307,7 +1307,7 @@ int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
/*
* Confirm all pages in a range [start, end) is belongs to the same zone.
*/
-static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
+int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct zone *zone = NULL;