Jiang Liu
2013-Mar-16 17:03 UTC
[PATCH v2, part3 10/12] mm: correctly update zone->mamaged_pages
Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. Signed-off-by: Jiang Liu <jiang.liu at huawei.com> Cc: Chris Metcalf <cmetcalf at tilera.com> Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk at oracle.com> Cc: Jeremy Fitzhardinge <jeremy at goop.org> Cc: Wen Congyang <wency at cn.fujitsu.com> Cc: Andrew Morton <akpm at linux-foundation.org> Cc: Tang Chen <tangchen at cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki at jp.fujitsu.com> Cc: Mel Gorman <mgorman at suse.de> Cc: Minchan Kim <minchan at kernel.org> Cc: linux-kernel at vger.kernel.org Cc: virtualization at lists.linux-foundation.org Cc: xen-devel at lists.xensource.com Cc: linux-mm at kvack.org --- drivers/virtio/virtio_balloon.c | 8 +++++--- drivers/xen/balloon.c | 23 +++++------------------ mm/hugetlb.c | 2 +- mm/memory_hotplug.c | 15 +++------------ mm/page_alloc.c | 10 +++++----- 5 files changed, 19 insertions(+), 39 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 797e1c7..4828c90 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -148,7 +148,7 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num) } set_page_pfns(vb->pfns + vb->num_pfns, page); vb->num_pages += VIRTIO_BALLOON_PAGES_PER_PAGE; - totalram_pages--; + adjust_managed_page_count(page, -1); } /* Did we get any? */ @@ -160,11 +160,13 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num) static void release_pages_by_pfn(const u32 pfns[], unsigned int num) { unsigned int i; + struct page *page; /* Find pfns pointing at start of each page, get pages and free them. */ for (i = 0; i < num; i += VIRTIO_BALLOON_PAGES_PER_PAGE) { - balloon_page_free(balloon_pfn_to_page(pfns[i])); - totalram_pages++; + page = balloon_pfn_to_page(pfns[i]); + balloon_page_free(page); + adjust_managed_page_count(page, 1); } } diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index a56776d..eefba39 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -89,14 +89,6 @@ EXPORT_SYMBOL_GPL(balloon_stats); /* We increase/decrease in batches which fit in a page */ static xen_pfn_t frame_list[PAGE_SIZE / sizeof(unsigned long)]; -#ifdef CONFIG_HIGHMEM -#define inc_totalhigh_pages() (totalhigh_pages++) -#define dec_totalhigh_pages() (totalhigh_pages--) -#else -#define inc_totalhigh_pages() do {} while (0) -#define dec_totalhigh_pages() do {} while (0) -#endif - /* List of ballooned pages, threaded through the mem_map array. */ static LIST_HEAD(ballooned_pages); @@ -132,9 +124,7 @@ static void __balloon_append(struct page *page) static void balloon_append(struct page *page) { __balloon_append(page); - if (PageHighMem(page)) - dec_totalhigh_pages(); - totalram_pages--; + adjust_managed_page_count(page, -1); } /* balloon_retrieve: rescue a page from the balloon, if it is not empty. */ @@ -151,13 +141,12 @@ static struct page *balloon_retrieve(bool prefer_highmem) page = list_entry(ballooned_pages.next, struct page, lru); list_del(&page->lru); - if (PageHighMem(page)) { + if (PageHighMem(page)) balloon_stats.balloon_high--; - inc_totalhigh_pages(); - } else + else balloon_stats.balloon_low--; - totalram_pages++; + adjust_managed_page_count(page, 1); return page; } @@ -372,9 +361,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages) #endif /* Relinquish the page back to the allocator. */ - ClearPageReserved(page); - init_page_count(page); - __free_page(page); + __free_reserved_page(page); } balloon_stats.current_pages += rc; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 344e7fe..4fb9a04 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1246,7 +1246,7 @@ static void __init gather_bootmem_prealloc(void) * side-effects, like CommitLimit going negative. */ if (h->order > (MAX_ORDER - 1)) - totalram_pages += 1 << h->order; + adjust_managed_page_count(page, 1 << h->order); } } diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index a1debd0..97454b3 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -760,20 +760,13 @@ EXPORT_SYMBOL_GPL(__online_page_set_limits); void __online_page_increment_counters(struct page *page) { - totalram_pages++; - -#ifdef CONFIG_HIGHMEM - if (PageHighMem(page)) - totalhigh_pages++; -#endif + adjust_managed_page_count(page, 1); } EXPORT_SYMBOL_GPL(__online_page_increment_counters); void __online_page_free(struct page *page) { - ClearPageReserved(page); - init_page_count(page); - __free_page(page); + __free_reserved_page(page); } EXPORT_SYMBOL_GPL(__online_page_free); @@ -970,7 +963,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ return ret; } - zone->managed_pages += onlined_pages; zone->present_pages += onlined_pages; zone->zone_pgdat->node_present_pages += onlined_pages; if (onlined_pages) { @@ -1554,10 +1546,9 @@ repeat: /* reset pagetype flags and makes migrate type to be MOVABLE */ undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); /* removal success */ - zone->managed_pages -= offlined_pages; + adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages); zone->present_pages -= offlined_pages; zone->zone_pgdat->node_present_pages -= offlined_pages; - totalram_pages -= offlined_pages; init_per_zone_wmark_min(); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b0ca2b7..6834104 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -775,11 +775,7 @@ void __init init_cma_reserved_pageblock(struct page *page) set_page_refcounted(page); set_pageblock_migratetype(page, MIGRATE_CMA); __free_pages(page, pageblock_order); - totalram_pages += pageblock_nr_pages; -#ifdef CONFIG_HIGHMEM - if (PageHighMem(page)) - totalhigh_pages += pageblock_nr_pages; -#endif + adjust_managed_page_count(page, pageblock_nr_pages); } #endif @@ -5128,6 +5124,10 @@ void adjust_managed_page_count(struct page *page, long count) page_zone(page)->managed_pages += count; totalram_pages += count; +#ifdef CONFIG_HIGHMEM + if (PageHighMem(page)) + totalhigh_pages += count; +#endif if (lock) spin_unlock(&managed_page_count_lock); -- 1.7.9.5