[PATCH 15/39] mm: pgrep: abstract page removal

Peter Zijlstra
2006-07-12T14:39:52Z

API:

Remove the specified page from the page reclaim data structures.

void __pgrep_remove(struct zone *zone, struct page *page);

NOTE: isolate_lru_page{,s}() become generic functions.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

include/linux/mm_page_replace.h | 1 +
include/linux/mm_use_once_policy.h | 9 +++++++++
include/linux/swap.h | 6 +++---
mm/migrate.c | 5 +----
mm/swap.c | 6 ++++--
mm/useonce.c | 8 ++------
mm/vmscan.c | 12 +++++-------
7 files changed, 25 insertions(+), 22 deletions(-)

Index: linux-2.6/include/linux/mm_page_replace.h
===================================================================
--- linux-2.6.orig/include/linux/mm_page_replace.h 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/include/linux/mm_page_replace.h 2006-07-12 16:11:44.000000000 +0200
@@ -84,6 +84,7 @@ extern unsigned long pgrep_shrink_zone(i
/* void pgrep_copy_state(struct page *, struct page *); */
/* void pgrep_clear_state(struct page *); */
/* int pgrep_is_active(struct page *); */
+/* void __pgrep_remove(struct zone *zone, struct page *page); */

#ifdef CONFIG_MM_POLICY_USEONCE
Index: linux-2.6/include/linux/mm_use_once_policy.h
===================================================================
--- linux-2.6.orig/include/linux/mm_use_once_policy.h 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/include/linux/mm_use_once_policy.h 2006-07-12 16:11:44.000000000 +0200
@@ -120,5 +120,14 @@ static inline int pgrep_is_active(struct
return PageActive(page);
}

+static inline void __pgrep_remove(struct zone *zone, struct page *page)
+{
+ list_del(&page->lru);
+ if (PageActive(page))
+ zone->nr_active--;
+ else
+ zone->nr_inactive--;
+}
+
#endif /* __KERNEL__ */
#endif /* _LINUX_MM_USEONCE_POLICY_H */
Index: linux-2.6/mm/migrate.c
===================================================================
--- linux-2.6.orig/mm/migrate.c 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/mm/migrate.c 2006-07-12 16:11:44.000000000 +0200
@@ -53,10 +53,7 @@ int isolate_lru_page(struct page *page,
ret = 0;
get_page(page);
ClearPageLRU(page);
- if (PageActive(page))
- del_page_from_active_list(zone, page);
- else
- del_page_from_inactive_list(zone, page);
+ __pgrep_remove(zone, page);
list_add_tail(&page->lru, pagelist);
}
spin_unlock_irq(&zone->lru_lock);
Index: linux-2.6/mm/swap.c
===================================================================
--- linux-2.6.orig/mm/swap.c 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/mm/swap.c 2006-07-12 16:11:44.000000000 +0200
@@ -140,7 +140,8 @@ void fastcall __page_cache_release(struc
spin_lock_irqsave(&zone->lru_lock, flags);
BUG_ON(!PageLRU(page));
__ClearPageLRU(page);
- del_page_from_lru(zone, page);
+ __pgrep_remove(zone, page);
+ pgrep_clear_state(page);
spin_unlock_irqrestore(&zone->lru_lock, flags);
}
free_hot_page(page);
@@ -191,7 +192,8 @@ void release_pages(struct page **pages,
}
BUG_ON(!PageLRU(page));
__ClearPageLRU(page);
- del_page_from_lru(zone, page);
+ __pgrep_remove(zone, page);
+ pgrep_clear_state(page);
}

if (!pagevec_add(&pages_to_free, page)) {
Index: linux-2.6/mm/useonce.c
===================================================================
--- linux-2.6.orig/mm/useonce.c 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/mm/useonce.c 2006-07-12 16:11:43.000000000 +0200
@@ -73,11 +73,9 @@ static unsigned long shrink_inactive_lis
unsigned long nr_scan;
unsigned long nr_freed;

- nr_taken = isolate_lru_pages(sc->swap_cluster_max,
+ nr_taken = isolate_lru_pages(zone, sc->swap_cluster_max,
&zone->inactive_list,
&page_list, &nr_scan);
- zone->nr_inactive -= nr_taken;
- zone->pages_scanned += nr_scan;
spin_unlock_irq(&zone->lru_lock);

nr_scanned += nr_scan;
@@ -155,10 +153,8 @@ static void shrink_active_list(unsigned

pgrep_add_drain();
spin_lock_irq(&zone->lru_lock);
- pgmoved = isolate_lru_pages(nr_pages, &zone->active_list,
+ pgmoved = isolate_lru_pages(zone, nr_pages, &zone->active_list,
&l_hold, &pgscanned);
- zone->pages_scanned += pgscanned;
- zone->nr_active -= pgmoved;
spin_unlock_irq(&zone->lru_lock);

while (!list_empty(&l_hold)) {
Index: linux-2.6/mm/vmscan.c
===================================================================
--- linux-2.6.orig/mm/vmscan.c 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/mm/vmscan.c 2006-07-12 16:11:44.000000000 +0200
@@ -514,7 +514,7 @@ keep:
*
* returns how many pages were moved onto *@dst.
*/
-unsigned long isolate_lru_pages(unsigned long nr_to_scan,
+unsigned long isolate_lru_pages(struct zone *zone, unsigned long nr_to_scan,
struct list_head *src, struct list_head *dst,
unsigned long *scanned)
{
@@ -523,14 +523,11 @@ unsigned long isolate_lru_pages(unsigned
unsigned long scan;

for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) {
- struct list_head *target;
page = lru_to_page(src);
prefetchw_prev_lru_page(page, src, flags);

BUG_ON(!PageLRU(page));

- list_del(&page->lru);
- target = src;
if (likely(get_page_unless_zero(page))) {
/*
* Be careful not to clear PageLRU until after we're
@@ -538,14 +535,15 @@ unsigned long isolate_lru_pages(unsigned
* page release code relies on it.
*/
ClearPageLRU(page);
- target = dst;
+ __pgrep_remove(zone, page);
+ list_add(&page->lru, dst);
nr_taken++;
} /* else it is being freed elsewhere */
-
- list_add(&page->lru, target);
+ else list_move(&page->lru, src);
}

*scanned = scan;
+ zone->pages_scanned += scan;
return nr_taken;
}

Index: linux-2.6/include/linux/swap.h
===================================================================
--- linux-2.6.orig/include/linux/swap.h 2006-07-12 16:09:18.000000000 +0200
+++ linux-2.6/include/linux/swap.h 2006-07-12 16:09:18.000000000 +0200
@@ -174,9 +174,9 @@ extern void release_pages(struct page **
extern int remove_mapping(struct address_space *mapping, struct page *page);
extern unsigned long shrink_page_list(struct list_head *page_list,
struct scan_control *sc);
-extern unsigned long isolate_lru_pages(unsigned long nr_to_scan,
- struct list_head *src, struct list_head *dst,
- unsigned long *scanned);
+extern unsigned long isolate_lru_pages(struct zone *zone,
+ unsigned long nr_to_scan, struct list_head *src,
+ struct list_head *dst, unsigned long *scanned);
extern int should_reclaim_mapped(struct zone *zone);
extern unsigned long try_to_free_pages(struct zone **, gfp_t);
extern unsigned long shrink_all_memory(unsigned long nr_pages);