memory hotplug: rearrange memory hotplug notifier
Current memory notifier has some defects yet. (Fortunately, nothing uses
it.) This patch is to fix and rearrange for them.
- Add information of start_pfn, nr_pages, and node id if node status is
changes from/to memoryless node for callback functions.
Callbacks can't do anything without those information.
- Add notification going-online status.
It is necessary for creating per node structure before the node's
pages are available.
- Move GOING_OFFLINE status notification after page isolation.
It is good place for return memory like cache for callback,
because returned page is not used again.
- Make CANCEL events for rollingback when error occurs.
- Delete MEM_MAPPING_INVALID notification. It will be not used.
- Fix compile error of (un)register_memory_notifier().
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 1833879..3a47871 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -187,7 +187,24 @@
unsigned long onlined_pages = 0;
struct zone *zone;
int need_zonelists_rebuild = 0;
+ int nid;
+ int ret;
+ struct memory_notify arg;
+ arg.start_pfn = pfn;
+ arg.nr_pages = nr_pages;
+ arg.status_change_nid = -1;
+
+ nid = page_to_nid(pfn_to_page(pfn));
+ if (node_present_pages(nid) == 0)
+ arg.status_change_nid = nid;
+
+ ret = memory_notify(MEM_GOING_ONLINE, &arg);
+ ret = notifier_to_errno(ret);
+ if (ret) {
+ memory_notify(MEM_CANCEL_ONLINE, &arg);
+ return ret;
+ }
/*
* This doesn't need a lock to do pfn_to_page().
* The section can't be removed here because of the
@@ -222,6 +239,10 @@
build_all_zonelists();
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
+
+ if (onlined_pages)
+ memory_notify(MEM_ONLINE, &arg);
+
return 0;
}
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
@@ -467,8 +488,9 @@
{
unsigned long pfn, nr_pages, expire;
long offlined_pages;
- int ret, drain, retry_max;
+ int ret, drain, retry_max, node;
struct zone *zone;
+ struct memory_notify arg;
BUG_ON(start_pfn >= end_pfn);
/* at least, alignment against pageblock is necessary */
@@ -480,11 +502,27 @@
we assume this for now. .*/
if (!test_pages_in_a_zone(start_pfn, end_pfn))
return -EINVAL;
+
+ zone = page_zone(pfn_to_page(start_pfn));
+ node = zone_to_nid(zone);
+ nr_pages = end_pfn - start_pfn;
+
/* set above range as isolated */
ret = start_isolate_page_range(start_pfn, end_pfn);
if (ret)
return ret;
- nr_pages = end_pfn - start_pfn;
+
+ arg.start_pfn = start_pfn;
+ arg.nr_pages = nr_pages;
+ arg.status_change_nid = -1;
+ if (nr_pages >= node_present_pages(node))
+ arg.status_change_nid = node;
+
+ ret = memory_notify(MEM_GOING_OFFLINE, &arg);
+ ret = notifier_to_errno(ret);
+ if (ret)
+ goto failed_removal;
+
pfn = start_pfn;
expire = jiffies + timeout;
drain = 0;
@@ -539,20 +577,24 @@
/* reset pagetype flags */
start_isolate_page_range(start_pfn, end_pfn);
/* removal success */
- zone = page_zone(pfn_to_page(start_pfn));
zone->present_pages -= offlined_pages;
zone->zone_pgdat->node_present_pages -= offlined_pages;
totalram_pages -= offlined_pages;
num_physpages -= offlined_pages;
+
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
+
+ memory_notify(MEM_OFFLINE, &arg);
return 0;
failed_removal:
printk(KERN_INFO "memory offlining %lx to %lx failed\n",
start_pfn, end_pfn);
+ memory_notify(MEM_CANCEL_OFFLINE, &arg);
/* pushback to free area */
undo_isolate_page_range(start_pfn, end_pfn);
+
return ret;
}
#else