Re: [PATCH v8, part3 12/14] mm: correctly update zone->mamaged_pages

From: Sergei Shtylyov
Date: Mon May 27 2013 - 09:57:17 EST


On 26-05-2013 17:38, Jiang Liu wrote:

Typo in the subject: s/mamaged_pages/managed_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@xxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Cc: Wen Congyang <wency@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Tang Chen <tangchen@xxxxxxxxxxxxxx>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
---
drivers/virtio/virtio_balloon.c | 8 +++++---
drivers/xen/balloon.c | 23 +++++------------------
mm/hugetlb.c | 2 +-
mm/memory_hotplug.c | 16 +++-------------
mm/page_alloc.c | 10 +++++-----
5 files changed, 19 insertions(+), 40 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
[...]
@@ -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;

Why not declare it right in the *for* loop? You could use intializer then...


/* 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);
}
}

[...]

WBR, Sergei

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/