* [PATCH] qemu-kvm: Change balloon page size to 1MB
@ 2012-02-20 17:34 Prasad Joshi
2012-02-20 17:34 ` [PATCH] virtio-balloon: " Prasad Joshi
0 siblings, 1 reply; 3+ messages in thread
From: Prasad Joshi @ 2012-02-20 17:34 UTC (permalink / raw)
To: prasadjoshi.linux; +Cc: amit.shah, kvm, avi
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
---
hw/virtio-balloon.c | 2 +-
hw/virtio-balloon.h | 6 +++++-
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c
index ce9d2c9..765dd97 100644
--- a/hw/virtio-balloon.c
+++ b/hw/virtio-balloon.c
@@ -48,7 +48,7 @@ static void balloon_page(void *addr, int deflate)
{
#if defined(__linux__)
if (!kvm_enabled() || kvm_has_sync_mmu())
- qemu_madvise(addr, TARGET_PAGE_SIZE,
+ qemu_madvise(addr, BALLOON_PAGE_SIZE,
deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED);
#endif
}
diff --git a/hw/virtio-balloon.h b/hw/virtio-balloon.h
index 73300dd..0da82bf 100644
--- a/hw/virtio-balloon.h
+++ b/hw/virtio-balloon.h
@@ -28,7 +28,11 @@
#define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory stats virtqueue */
/* Size of a PFN in the balloon interface. */
-#define VIRTIO_BALLOON_PFN_SHIFT 12
+#define VIRTIO_BALLOON_PFN_SHIFT 20
+
+/* Size of the balloon page */
+#define BALLOON_PAGE_SIZE (1UL << VIRTIO_BALLOON_PFN_SHIFT)
+
struct virtio_balloon_config
{
--
1.7.5.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH] virtio-balloon: Change balloon page size to 1MB
2012-02-20 17:34 [PATCH] qemu-kvm: Change balloon page size to 1MB Prasad Joshi
@ 2012-02-20 17:34 ` Prasad Joshi
2012-02-21 23:03 ` Anthony Liguori
0 siblings, 1 reply; 3+ messages in thread
From: Prasad Joshi @ 2012-02-20 17:34 UTC (permalink / raw)
To: prasadjoshi.linux; +Cc: amit.shah, kvm, avi
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
---
drivers/virtio/virtio_balloon.c | 18 +++++++++---------
include/linux/virtio_balloon.h | 4 +++-
2 files changed, 12 insertions(+), 10 deletions(-)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 95aeedf..e352448 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -64,9 +64,8 @@ static u32 page_to_balloon_pfn(struct page *page)
{
unsigned long pfn = page_to_pfn(page);
- BUILD_BUG_ON(PAGE_SHIFT < VIRTIO_BALLOON_PFN_SHIFT);
/* Convert pfn from Linux page size to balloon page size. */
- return pfn >> (PAGE_SHIFT - VIRTIO_BALLOON_PFN_SHIFT);
+ return pfn >> VIRTIO_BALLOON_PAGE_ORDER;
}
static void balloon_ack(struct virtqueue *vq)
@@ -102,8 +101,9 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
num = min(num, ARRAY_SIZE(vb->pfns));
for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) {
- struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY |
- __GFP_NOMEMALLOC | __GFP_NOWARN);
+ struct page *page = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY |
+ __GFP_NOMEMALLOC | __GFP_NOWARN,
+ VIRTIO_BALLOON_PAGE_ORDER);
if (!page) {
if (printk_ratelimit())
dev_printk(KERN_INFO, &vb->vdev->dev,
@@ -114,7 +114,7 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
break;
}
vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page);
- totalram_pages--;
+ totalram_pages -= VIRTIO_BALLOON_PAGES;
vb->num_pages++;
list_add(&page->lru, &vb->pages);
}
@@ -131,8 +131,8 @@ static void release_pages_by_pfn(const u32 pfns[], unsigned int num)
unsigned int i;
for (i = 0; i < num; i++) {
- __free_page(pfn_to_page(pfns[i]));
- totalram_pages++;
+ __free_pages(pfn_to_page(pfns[i]), VIRTIO_BALLOON_PAGE_ORDER);
+ totalram_pages += VIRTIO_BALLOON_PAGES;
}
}
@@ -146,7 +146,7 @@ static void leak_balloon(struct virtio_balloon *vb, size_t num)
for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) {
page = list_first_entry(&vb->pages, struct page, lru);
list_del(&page->lru);
- vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page);
+ vb->pfns[vb->num_pfns] = page_to_pfn(page);
vb->num_pages--;
}
@@ -400,7 +400,7 @@ static int virtballoon_restore(struct virtio_device *vdev)
/* We don't have these pages in the balloon anymore! */
list_for_each_entry_safe(page, page2, &vb->pages, lru) {
list_del(&page->lru);
- totalram_pages++;
+ totalram_pages += VIRTIO_BALLOON_PAGES;
}
return init_vqs(vdev->priv);
}
diff --git a/include/linux/virtio_balloon.h b/include/linux/virtio_balloon.h
index 652dc8b..86840fe 100644
--- a/include/linux/virtio_balloon.h
+++ b/include/linux/virtio_balloon.h
@@ -33,7 +33,9 @@
#define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */
/* Size of a PFN in the balloon interface. */
-#define VIRTIO_BALLOON_PFN_SHIFT 12
+#define VIRTIO_BALLOON_PFN_SHIFT 20
+#define VIRTIO_BALLOON_PAGE_ORDER (VIRTIO_BALLOON_PFN_SHIFT - PAGE_SHIFT)
+#define VIRTIO_BALLOON_PAGES (1U << VIRTIO_BALLOON_PAGE_ORDER)
struct virtio_balloon_config
{
--
1.7.4.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] virtio-balloon: Change balloon page size to 1MB
2012-02-20 17:34 ` [PATCH] virtio-balloon: " Prasad Joshi
@ 2012-02-21 23:03 ` Anthony Liguori
0 siblings, 0 replies; 3+ messages in thread
From: Anthony Liguori @ 2012-02-21 23:03 UTC (permalink / raw)
To: Prasad Joshi; +Cc: amit.shah, kvm, avi
On 02/20/2012 11:34 AM, Prasad Joshi wrote:
> Signed-off-by: Prasad Joshi<prasadjoshi.linux@gmail.com>
This breaks compatibility with existing guests and more importantly, doesn't
make any sense. There's no commit message explaining why 1MB is a better number
than 4K, 2MB which I could at least understand as an alternative to 4K.
Regards,
Anthony Liguori
> ---
> drivers/virtio/virtio_balloon.c | 18 +++++++++---------
> include/linux/virtio_balloon.h | 4 +++-
> 2 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 95aeedf..e352448 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -64,9 +64,8 @@ static u32 page_to_balloon_pfn(struct page *page)
> {
> unsigned long pfn = page_to_pfn(page);
>
> - BUILD_BUG_ON(PAGE_SHIFT< VIRTIO_BALLOON_PFN_SHIFT);
> /* Convert pfn from Linux page size to balloon page size. */
> - return pfn>> (PAGE_SHIFT - VIRTIO_BALLOON_PFN_SHIFT);
> + return pfn>> VIRTIO_BALLOON_PAGE_ORDER;
> }
>
> static void balloon_ack(struct virtqueue *vq)
> @@ -102,8 +101,9 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
> num = min(num, ARRAY_SIZE(vb->pfns));
>
> for (vb->num_pfns = 0; vb->num_pfns< num; vb->num_pfns++) {
> - struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY |
> - __GFP_NOMEMALLOC | __GFP_NOWARN);
> + struct page *page = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY |
> + __GFP_NOMEMALLOC | __GFP_NOWARN,
> + VIRTIO_BALLOON_PAGE_ORDER);
> if (!page) {
> if (printk_ratelimit())
> dev_printk(KERN_INFO,&vb->vdev->dev,
> @@ -114,7 +114,7 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
> break;
> }
> vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page);
> - totalram_pages--;
> + totalram_pages -= VIRTIO_BALLOON_PAGES;
> vb->num_pages++;
> list_add(&page->lru,&vb->pages);
> }
> @@ -131,8 +131,8 @@ static void release_pages_by_pfn(const u32 pfns[], unsigned int num)
> unsigned int i;
>
> for (i = 0; i< num; i++) {
> - __free_page(pfn_to_page(pfns[i]));
> - totalram_pages++;
> + __free_pages(pfn_to_page(pfns[i]), VIRTIO_BALLOON_PAGE_ORDER);
> + totalram_pages += VIRTIO_BALLOON_PAGES;
> }
> }
>
> @@ -146,7 +146,7 @@ static void leak_balloon(struct virtio_balloon *vb, size_t num)
> for (vb->num_pfns = 0; vb->num_pfns< num; vb->num_pfns++) {
> page = list_first_entry(&vb->pages, struct page, lru);
> list_del(&page->lru);
> - vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page);
> + vb->pfns[vb->num_pfns] = page_to_pfn(page);
> vb->num_pages--;
> }
>
> @@ -400,7 +400,7 @@ static int virtballoon_restore(struct virtio_device *vdev)
> /* We don't have these pages in the balloon anymore! */
> list_for_each_entry_safe(page, page2,&vb->pages, lru) {
> list_del(&page->lru);
> - totalram_pages++;
> + totalram_pages += VIRTIO_BALLOON_PAGES;
> }
> return init_vqs(vdev->priv);
> }
> diff --git a/include/linux/virtio_balloon.h b/include/linux/virtio_balloon.h
> index 652dc8b..86840fe 100644
> --- a/include/linux/virtio_balloon.h
> +++ b/include/linux/virtio_balloon.h
> @@ -33,7 +33,9 @@
> #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */
>
> /* Size of a PFN in the balloon interface. */
> -#define VIRTIO_BALLOON_PFN_SHIFT 12
> +#define VIRTIO_BALLOON_PFN_SHIFT 20
> +#define VIRTIO_BALLOON_PAGE_ORDER (VIRTIO_BALLOON_PFN_SHIFT - PAGE_SHIFT)
> +#define VIRTIO_BALLOON_PAGES (1U<< VIRTIO_BALLOON_PAGE_ORDER)
>
> struct virtio_balloon_config
> {
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-02-21 23:03 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-02-20 17:34 [PATCH] qemu-kvm: Change balloon page size to 1MB Prasad Joshi
2012-02-20 17:34 ` [PATCH] virtio-balloon: " Prasad Joshi
2012-02-21 23:03 ` Anthony Liguori
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.