[PATCH V2 10/12] hv_balloon: simplify hv_online_page()/hv_page_online_one()

From: kys
Date: Mon Mar 05 2018 - 00:20:29 EST


From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

Instead of doing pfn_to_page() and continuosly casting page to unsigned
long just cache the pfn of the page with page_to_pfn().

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/hv_balloon.c | 27 +++++----------------------
1 file changed, 5 insertions(+), 22 deletions(-)

diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 1aece72da9ba..5b8e1ad1bcfe 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -612,28 +612,17 @@ static struct notifier_block hv_memory_nb = {
/* Check if the particular page is backed and can be onlined and online it. */
static void hv_page_online_one(struct hv_hotadd_state *has, struct page *pg)
{
- unsigned long cur_start_pgp;
- unsigned long cur_end_pgp;
struct hv_hotadd_gap *gap;
-
- cur_start_pgp = (unsigned long)pfn_to_page(has->covered_start_pfn);
- cur_end_pgp = (unsigned long)pfn_to_page(has->covered_end_pfn);
+ unsigned long pfn = page_to_pfn(pg);

/* The page is not backed. */
- if (((unsigned long)pg < cur_start_pgp) ||
- ((unsigned long)pg >= cur_end_pgp))
+ if ((pfn < has->covered_start_pfn) || (pfn >= has->covered_end_pfn))
return;

/* Check for gaps. */
list_for_each_entry(gap, &has->gap_list, list) {
- cur_start_pgp = (unsigned long)
- pfn_to_page(gap->start_pfn);
- cur_end_pgp = (unsigned long)
- pfn_to_page(gap->end_pfn);
- if (((unsigned long)pg >= cur_start_pgp) &&
- ((unsigned long)pg < cur_end_pgp)) {
+ if ((pfn >= gap->start_pfn) && (pfn < gap->end_pfn))
return;
- }
}

/* This frame is currently backed; online the page. */
@@ -726,19 +715,13 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size,
static void hv_online_page(struct page *pg)
{
struct hv_hotadd_state *has;
- unsigned long cur_start_pgp;
- unsigned long cur_end_pgp;
unsigned long flags;
+ unsigned long pfn = page_to_pfn(pg);

spin_lock_irqsave(&dm_device.ha_lock, flags);
list_for_each_entry(has, &dm_device.ha_region_list, list) {
- cur_start_pgp = (unsigned long)
- pfn_to_page(has->start_pfn);
- cur_end_pgp = (unsigned long)pfn_to_page(has->end_pfn);
-
/* The page belongs to a different HAS. */
- if (((unsigned long)pg < cur_start_pgp) ||
- ((unsigned long)pg >= cur_end_pgp))
+ if ((pfn < has->start_pfn) || (pfn >= has->end_pfn))
continue;

hv_page_online_one(has, pg);
--
2.15.1