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| author | Hugh Dickins <hugh@veritas.com> | 2009-01-06 23:39:41 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-07 00:59:04 +0100 |
| commit | b962716b459505a8d83aea313fea0abe76749f42 (patch) | |
| tree | b401e882f2ee8ff5a11209057496e603c211e8fe | |
| parent | mm: add add_to_swap stub (diff) | |
| download | linux-b962716b459505a8d83aea313fea0abe76749f42.tar.xz linux-b962716b459505a8d83aea313fea0abe76749f42.zip | |
mm: optimize get_scan_ratio for no swap
Rik suggests a simplified get_scan_ratio() for !CONFIG_SWAP. Yes, the gcc
optimizer gives us that, when nr_swap_pages is #defined as 0L. Move usual
declaration to swapfile.c: it never belonged in page_alloc.c.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/swap.h | 5 | ||||
| -rw-r--r-- | mm/page_alloc.c | 1 | ||||
| -rw-r--r-- | mm/swapfile.c | 1 | ||||
| -rw-r--r-- | mm/vmscan.c | 12 |
4 files changed, 10 insertions, 9 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index c0d23ac710d5..3a31cc25bd2c 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -163,7 +163,6 @@ struct swap_list_t { /* linux/mm/page_alloc.c */ extern unsigned long totalram_pages; extern unsigned long totalreserve_pages; -extern long nr_swap_pages; extern unsigned int nr_free_buffer_pages(void); extern unsigned int nr_free_pagecache_pages(void); @@ -291,6 +290,7 @@ extern struct page *swapin_readahead(swp_entry_t, gfp_t, struct vm_area_struct *vma, unsigned long addr); /* linux/mm/swapfile.c */ +extern long nr_swap_pages; extern long total_swap_pages; extern void si_swapinfo(struct sysinfo *); extern swp_entry_t get_swap_page(void); @@ -331,7 +331,8 @@ static inline void disable_swap_token(void) #else /* CONFIG_SWAP */ -#define total_swap_pages 0 +#define nr_swap_pages 0L +#define total_swap_pages 0L #define total_swapcache_pages 0UL #define si_swapinfo(val) \ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ce2a026219bc..65133436fe3d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -69,7 +69,6 @@ EXPORT_SYMBOL(node_states); unsigned long totalram_pages __read_mostly; unsigned long totalreserve_pages __read_mostly; -long nr_swap_pages; int percpu_pagelist_fraction; #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE diff --git a/mm/swapfile.c b/mm/swapfile.c index 9ce7f81c8abc..725e56c362de 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -35,6 +35,7 @@ static DEFINE_SPINLOCK(swap_lock); static unsigned int nr_swapfiles; +long nr_swap_pages; long total_swap_pages; static int swap_overflow; static int least_priority; diff --git a/mm/vmscan.c b/mm/vmscan.c index f350523a8eee..d500b906746c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1327,12 +1327,6 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc, unsigned long anon_prio, file_prio; unsigned long ap, fp; - anon = zone_page_state(zone, NR_ACTIVE_ANON) + - zone_page_state(zone, NR_INACTIVE_ANON); - file = zone_page_state(zone, NR_ACTIVE_FILE) + - zone_page_state(zone, NR_INACTIVE_FILE); - free = zone_page_state(zone, NR_FREE_PAGES); - /* If we have no swap space, do not bother scanning anon pages. */ if (nr_swap_pages <= 0) { percent[0] = 0; @@ -1340,6 +1334,12 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc, return; } + anon = zone_page_state(zone, NR_ACTIVE_ANON) + + zone_page_state(zone, NR_INACTIVE_ANON); + file = zone_page_state(zone, NR_ACTIVE_FILE) + + zone_page_state(zone, NR_INACTIVE_FILE); + free = zone_page_state(zone, NR_FREE_PAGES); + /* If we have very few page cache pages, force-scan anon pages. */ if (unlikely(file + free <= zone->pages_high)) { percent[0] = 100; |