diff options
| -rw-r--r-- | include/linux/memory_hotplug.h | 4 | ||||
| -rw-r--r-- | mm/memory_hotplug.c | 17 | ||||
| -rw-r--r-- | mm/page_alloc.c | 87 |
3 files changed, 72 insertions, 36 deletions
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 864035fb8f8a..4307231bd22f 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -70,6 +70,10 @@ extern void online_page(struct page *page); extern int online_pages(unsigned long, unsigned long); extern void __offline_isolated_pages(unsigned long, unsigned long); +#ifdef CONFIG_MEMORY_HOTREMOVE +extern bool is_pageblock_removable_nolock(struct page *page); +#endif /* CONFIG_MEMORY_HOTREMOVE */ + /* reasonably generic interface to expand the physical pages in a zone */ extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn, unsigned long nr_pages); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 4821338b4e4b..b0dc65452973 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -602,27 +602,14 @@ static struct page *next_active_pageblock(struct page *page) /* Checks if this range of memory is likely to be hot-removable. */ int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) { - int type; struct page *page = pfn_to_page(start_pfn); struct page *end_page = page + nr_pages; /* Check the starting page of each pageblock within the range */ for (; page < end_page; page = next_active_pageblock(page)) { - type = get_pageblock_migratetype(page); - - /* - * A pageblock containing MOVABLE or free pages is considered - * removable - */ - if (type != MIGRATE_MOVABLE && !pageblock_free(page)) - return 0; - - /* - * A pageblock starting with a PageReserved page is not - * considered removable. - */ - if (PageReserved(page)) + if (!is_pageblock_removable_nolock(page)) return 0; + cond_resched(); } /* All pageblocks in the memory block are likely to be hot-removable */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 099790052bfe..6a683f819439 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5297,12 +5297,65 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags, * page allocater never alloc memory from ISOLATE block. */ +static int +__count_immobile_pages(struct zone *zone, struct page *page, int count) +{ + unsigned long pfn, iter, found; + /* + * For avoiding noise data, lru_add_drain_all() should be called + * If ZONE_MOVABLE, the zone never contains immobile pages + */ + if (zone_idx(zone) == ZONE_MOVABLE) + return true; + + if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE) + return true; + + pfn = page_to_pfn(page); + for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) { + unsigned long check = pfn + iter; + + if (!pfn_valid_within(check)) { + iter++; + continue; + } + page = pfn_to_page(check); + if (!page_count(page)) { + if (PageBuddy(page)) + iter += (1 << page_order(page)) - 1; + continue; + } + if (!PageLRU(page)) + found++; + /* + * If there are RECLAIMABLE pages, we need to check it. + * But now, memory offline itself doesn't call shrink_slab() + * and it still to be fixed. + */ + /* + * If the page is not RAM, page_count()should be 0. + * we don't need more check. This is an _used_ not-movable page. + * + * The problematic thing here is PG_reserved pages. PG_reserved + * is set to both of a memory hole page and a _used_ kernel + * page at boot. + */ + if (found > count) + return false; + } + return true; +} + +bool is_pageblock_removable_nolock(struct page *page) +{ + struct zone *zone = page_zone(page); + return __count_immobile_pages(zone, page, 0); +} + int set_migratetype_isolate(struct page *page) { struct zone *zone; - struct page *curr_page; - unsigned long flags, pfn, iter; - unsigned long immobile = 0; + unsigned long flags, pfn; struct memory_isolate_notify arg; int notifier_ret; int ret = -EBUSY; @@ -5312,11 +5365,6 @@ int set_migratetype_isolate(struct page *page) zone_idx = zone_idx(zone); spin_lock_irqsave(&zone->lock, flags); - if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE || - zone_idx == ZONE_MOVABLE) { - ret = 0; - goto out; - } pfn = page_to_pfn(page); arg.start_pfn = pfn; @@ -5338,21 +5386,18 @@ int set_migratetype_isolate(struct page *page) notifier_ret = notifier_to_errno(notifier_ret); if (notifier_ret) goto out; - - for (iter = pfn; iter < (pfn + pageblock_nr_pages); iter++) { - if (!pfn_valid_within(pfn)) - continue; - - curr_page = pfn_to_page(iter); - if (!page_count(curr_page) || PageLRU(curr_page)) - continue; - - immobile++; - } - - if (arg.pages_found == immobile) + /* + * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself. + * We just check MOVABLE pages. + */ + if (__count_immobile_pages(zone, page, arg.pages_found)) ret = 0; + /* + * immobile means "not-on-lru" paes. If immobile is larger than + * removable-by-driver pages reported by notifier, we'll fail. + */ + out: if (!ret) { set_pageblock_migratetype(page, MIGRATE_ISOLATE); |