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| author | KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> | 2007-10-16 12:26:12 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-16 20:43:02 +0400 |
| commit | 0c0e6195896535481173df98935ad8db174f4d45 (patch) | |
| tree | 2b35d3b81ba54b5d38e691d2a2019f4bcdfd1dce /mm/page_alloc.c | |
| parent | a5d76b54a3f3a40385d7f76069a2feac9f1bad63 (diff) | |
| download | linux-0c0e6195896535481173df98935ad8db174f4d45.tar.xz | |
memory unplug: page offline
Logic.
- set all pages in [start,end) as isolated migration-type.
by this, all free pages in the range will be not-for-use.
- Migrate all LRU pages in the range.
- Test all pages in the range's refcnt is zero or not.
Todo:
- allocate migration destination page from better area.
- confirm page_count(page)== 0 && PageReserved(page) page is safe to be freed..
(I don't like this kind of page but..
- Find out pages which cannot be migrated.
- more running tests.
- Use reclaim for unplugging other memory type area.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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>
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a44715e82058..d315e1127dc9 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4477,3 +4477,50 @@ void unset_migratetype_isolate(struct page *page) out: spin_unlock_irqrestore(&zone->lock, flags); } + +#ifdef CONFIG_MEMORY_HOTREMOVE +/* + * All pages in the range must be isolated before calling this. + */ +void +__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) +{ + struct page *page; + struct zone *zone; + int order, i; + unsigned long pfn; + unsigned long flags; + /* find the first valid pfn */ + for (pfn = start_pfn; pfn < end_pfn; pfn++) + if (pfn_valid(pfn)) + break; + if (pfn == end_pfn) + return; + zone = page_zone(pfn_to_page(pfn)); + spin_lock_irqsave(&zone->lock, flags); + pfn = start_pfn; + while (pfn < end_pfn) { + if (!pfn_valid(pfn)) { + pfn++; + continue; + } + page = pfn_to_page(pfn); + BUG_ON(page_count(page)); + BUG_ON(!PageBuddy(page)); + order = page_order(page); +#ifdef CONFIG_DEBUG_VM + printk(KERN_INFO "remove from free list %lx %d %lx\n", + pfn, 1 << order, end_pfn); +#endif + list_del(&page->lru); + rmv_page_order(page); + zone->free_area[order].nr_free--; + __mod_zone_page_state(zone, NR_FREE_PAGES, + - (1UL << order)); + for (i = 0; i < (1 << order); i++) + SetPageReserved((page+i)); + pfn += (1 << order); + } + spin_unlock_irqrestore(&zone->lock, flags); +} +#endif |