Nikita Danilov <Nikita@Namesys.COM> wrote:
>
> This fragment of refill_inactive_zone() looks strange:
>
> list_move(&page->lru, &zone->inactive_list);
> if (!pagevec_add(&pvec, page)) {
> spin_unlock_irq(&zone->lru_lock);
> if (buffer_heads_over_limit)
> pagevec_strip(&pvec);
> __pagevec_release(&pvec);
> spin_lock_irq(&zone->lru_lock);
> }
>
Thanks, you're dead right. That's buggy.
I am fairly surprised that you were able to hit this. How are you doing
it? On a 1G machine with a teeny ZONE_HIGHMEM??
I haven't tested this yet, but it should fix it up.
diff -puN mm/vmscan.c~nr_inactive-race-fix mm/vmscan.c
--- 25/mm/vmscan.c~nr_inactive-race-fix Mon Apr 21 15:15:48 2003
+++ 25-akpm/mm/vmscan.c Mon Apr 21 15:30:33 2003
@@ -557,6 +557,7 @@ static void
refill_inactive_zone(struct zone *zone, const int nr_pages_in,
struct page_state *ps, int priority)
{
+ int pgmoved;
int pgdeactivate = 0;
int nr_pages = nr_pages_in;
LIST_HEAD(l_hold); /* The pages which were snipped off */
@@ -570,6 +571,7 @@ refill_inactive_zone(struct zone *zone,
long swap_tendency;
lru_add_drain();
+ pgmoved = 0;
spin_lock_irq(&zone->lru_lock);
while (nr_pages && !list_empty(&zone->active_list)) {
page = list_entry(zone->active_list.prev, struct page, lru);
@@ -584,9 +586,12 @@ refill_inactive_zone(struct zone *zone,
} else {
page_cache_get(page);
list_add(&page->lru, &l_hold);
+ pgmoved++;
}
nr_pages--;
}
+ zone->nr_active -= pgmoved;
+ zone->nr_inactive += pgmoved;
spin_unlock_irq(&zone->lru_lock);
/*
@@ -646,10 +651,10 @@ refill_inactive_zone(struct zone *zone,
continue;
}
list_add(&page->lru, &l_inactive);
- pgdeactivate++;
}
pagevec_init(&pvec, 1);
+ pgmoved = 0;
spin_lock_irq(&zone->lru_lock);
while (!list_empty(&l_inactive)) {
page = list_entry(l_inactive.prev, struct page, lru);
@@ -659,19 +664,27 @@ refill_inactive_zone(struct zone *zone,
if (!TestClearPageActive(page))
BUG();
list_move(&page->lru, &zone->inactive_list);
+ pgmoved++;
if (!pagevec_add(&pvec, page)) {
+ zone->nr_inactive += pgmoved;
spin_unlock_irq(&zone->lru_lock);
+ pgdeactivate += pgmoved;
+ pgmoved = 0;
if (buffer_heads_over_limit)
pagevec_strip(&pvec);
__pagevec_release(&pvec);
spin_lock_irq(&zone->lru_lock);
}
}
+ zone->nr_inactive += pgmoved;
+ pgdeactivate += pgmoved;
if (buffer_heads_over_limit) {
spin_unlock_irq(&zone->lru_lock);
pagevec_strip(&pvec);
spin_lock_irq(&zone->lru_lock);
}
+
+ pgmoved = 0;
while (!list_empty(&l_active)) {
page = list_entry(l_active.prev, struct page, lru);
prefetchw_prev_lru_page(page, &l_active, flags);
@@ -679,14 +692,16 @@ refill_inactive_zone(struct zone *zone,
BUG();
BUG_ON(!PageActive(page));
list_move(&page->lru, &zone->active_list);
+ pgmoved++;
if (!pagevec_add(&pvec, page)) {
+ zone->nr_active += pgmoved;
+ pgmoved = 0;
spin_unlock_irq(&zone->lru_lock);
__pagevec_release(&pvec);
spin_lock_irq(&zone->lru_lock);
}
}
- zone->nr_active -= pgdeactivate;
- zone->nr_inactive += pgdeactivate;
+ zone->nr_active += pgmoved;
spin_unlock_irq(&zone->lru_lock);
pagevec_release(&pvec);
_
-
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This archive was generated by hypermail 2b29 : Wed Apr 23 2003 - 22:00:31 EST