Jiang Liu
2013-May-17 15:45 UTC
[PATCH v7, part3 13/16] 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 bd3ae32..6649968 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 d42da3b..a453c05 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;
}
@@ -374,9 +363,7 @@ 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 f8feeec..95c5a6b 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 c291295..304ada7 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -769,20 +769,13 @@ 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);
@@ -979,7 +972,6 @@ 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) {
@@ -1563,10 +1555,9 @@ 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 a07e70a..56b0097 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -780,11 +780,7 @@ 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
@@ -5189,6 +5185,10 @@ void adjust_managed_page_count(struct page *page, long
count)
spin_lock(&managed_page_count_lock);
page_zone(page)->managed_pages += count;
totalram_pages += count;
+#ifdef CONFIG_HIGHMEM
+ if (PageHighMem(page))
+ totalhigh_pages += count;
+#endif
spin_unlock(&managed_page_count_lock);
}
EXPORT_SYMBOL(adjust_managed_page_count);
--
1.8.1.2