2002-10-04 22:55:14

by Matt D. Robinson

Subject: [PATCH] 2.5.40: lkcd (5/9): add in use for page alloc/free

This adds in-use tag for dump ordering capabilities (so
taht pages in use are dumped first).

diff -urN -X /home/bharata/dontdiff linux-2.5.40/include/linux/page-flags.h linux-2.5.40+lkcd/include/linux/page-flags.h
--- linux-2.5.40/include/linux/page-flags.h Tue Oct 1 12:37:31 2002
+++ linux-2.5.40+lkcd/include/linux/page-flags.h Thu Oct 3 07:21:23 2002
@@ -69,6 +69,7 @@

#define PG_direct 16 /* ->pte_chain points directly at pte */

+#define PG_inuse 17
/*
* Global page accounting. One instance per CPU.
*/
@@ -204,6 +205,10 @@
#define ClearPageDirect(page) clear_bit(PG_direct, &(page)->flags)
#define TestClearPageDirect(page) test_and_clear_bit(PG_direct, &(page)->flags)

+#define PageInuse(page) test_bit(PG_inuse, &(page)->flags)
+#define SetPageInuse(page) __set_bit(PG_inuse, &(page)->flags)
+#define ClearPageInuse(page) __clear_bit(PG_inuse, &(page)->flags)
+
/*
* The PageSwapCache predicate doesn't use a PG_flag at this time,
* but it may again do so one day.
diff -urN -X /home/bharata/dontdiff linux-2.5.40/mm/page_alloc.c linux-2.5.40+lkcd/mm/page_alloc.c
--- linux-2.5.40/mm/page_alloc.c Tue Oct 1 12:36:16 2002
+++ linux-2.5.40+lkcd/mm/page_alloc.c Thu Oct 3 07:21:23 2002
@@ -85,6 +85,14 @@
struct free_area *area;
struct page *base;
struct zone *zone;
+ unsigned int i;
+
+ i = 1UL << order;
+ page += i;
+ do {
+ page--;
+ ClearPageInuse(page);
+ } while (--i);

KERNEL_STAT_ADD(pgfree, 1<<order);

@@ -206,7 +214,7 @@
curr = head->next;

if (curr != head) {
- unsigned int index;
+ unsigned int index, i;

page = list_entry(curr, struct page, list);
BUG_ON(bad_range(zone, page));
@@ -221,6 +229,12 @@

if (bad_range(zone, page))
BUG();
+ i = 1UL << order;
+ page += i;
+ do {
+ page--;
+ SetPageInuse(page);
+ } while (--i);
prep_new_page(page);
return page;
}
@@ -276,6 +290,7 @@
struct list_head * entry, * local_pages;
struct page * tmp;
int nr_pages;
+ unsigned int i;

local_pages = &current->local_pages;

@@ -288,6 +303,12 @@
list_del(entry);
page = tmp;
current->nr_local_pages--;
+ i = 1UL << order;
+ page = tmp + i;
+ do {
+ page--;
+ SetPageInuse(page);
+ } while (--i);
prep_new_page(page);
break;
}