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mm: page_alloc: reduce number of times page_to_pfn is called

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In the free path we calculate page_to_pfn multiple times. Reduce that.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman 2014-06-04 16:10:17 -07:00 committed by Linus Torvalds
parent e58469bafd
commit dc4b0caff2
3 changed files with 39 additions and 37 deletions
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9
include/linux/mmzone.h
View File

@ -78,10 +78,15 @@ extern int page_group_by_mobility_disabled;
#define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
#define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
static inline int get_pageblock_migratetype(struct page *page)
#define get_pageblock_migratetype(page) \
get_pfnblock_flags_mask(page, page_to_pfn(page), \
PB_migrate_end, MIGRATETYPE_MASK)
static inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
{
BUILD_BUG_ON(PB_migrate_end - PB_migrate != 2);
return get_pageblock_flags_mask(page, PB_migrate_end, MIGRATETYPE_MASK);
return get_pfnblock_flags_mask(page, pfn, PB_migrate_end,
MIGRATETYPE_MASK);
}
struct free_area {

33
include/linux/pageblock-flags.h
View File

@ -65,33 +65,26 @@ extern int pageblock_order;
/* Forward declaration */
struct page;
unsigned long get_pageblock_flags_mask(struct page *page,
unsigned long get_pfnblock_flags_mask(struct page *page,
unsigned long pfn,
unsigned long end_bitidx,
unsigned long mask);
void set_pageblock_flags_mask(struct page *page,
void set_pfnblock_flags_mask(struct page *page,
unsigned long flags,
unsigned long pfn,
unsigned long end_bitidx,
unsigned long mask);
/* Declarations for getting and setting flags. See mm/page_alloc.c */
static inline unsigned long get_pageblock_flags_group(struct page *page,
int start_bitidx, int end_bitidx)
{
unsigned long nr_flag_bits = end_bitidx - start_bitidx + 1;
unsigned long mask = (1 << nr_flag_bits) - 1;
return get_pageblock_flags_mask(page, end_bitidx, mask);
}
static inline void set_pageblock_flags_group(struct page *page,
unsigned long flags,
int start_bitidx, int end_bitidx)
{
unsigned long nr_flag_bits = end_bitidx - start_bitidx + 1;
unsigned long mask = (1 << nr_flag_bits) - 1;
set_pageblock_flags_mask(page, flags, end_bitidx, mask);
}
#define get_pageblock_flags_group(page, start_bitidx, end_bitidx) \
get_pfnblock_flags_mask(page, page_to_pfn(page), \
end_bitidx, \
(1 << (end_bitidx - start_bitidx + 1)) - 1)
#define set_pageblock_flags_group(page, flags, start_bitidx, end_bitidx) \
set_pfnblock_flags_mask(page, flags, page_to_pfn(page), \
end_bitidx, \
(1 << (end_bitidx - start_bitidx + 1)) - 1)
#ifdef CONFIG_COMPACTION
#define get_pageblock_skip(page) \

34
mm/page_alloc.c
View File

@ -560,6 +560,7 @@ static inline int page_is_buddy(struct page *page, struct page *buddy,
*/
static inline void __free_one_page(struct page *page,
unsigned long pfn,
struct zone *zone, unsigned int order,
int migratetype)
{
@ -576,7 +577,7 @@ static inline void __free_one_page(struct page *page,
VM_BUG_ON(migratetype == -1);
page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
page_idx = pfn & ((1 << MAX_ORDER) - 1);
VM_BUG_ON_PAGE(page_idx & ((1 << order) - 1), page);
VM_BUG_ON_PAGE(bad_range(zone, page), page);
@ -711,7 +712,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
list_del(&page->lru);
mt = get_freepage_migratetype(page);
/* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
__free_one_page(page, zone, 0, mt);
__free_one_page(page, page_to_pfn(page), zone, 0, mt);
trace_mm_page_pcpu_drain(page, 0, mt);
if (likely(!is_migrate_isolate_page(page))) {
__mod_zone_page_state(zone, NR_FREE_PAGES, 1);
@ -723,13 +724,15 @@ static void free_pcppages_bulk(struct zone *zone, int count,
spin_unlock(&zone->lock);
}
static void free_one_page(struct zone *zone, struct page *page, int order,
static void free_one_page(struct zone *zone,
struct page *page, unsigned long pfn,
int order,
int migratetype)
{
spin_lock(&zone->lock);
zone->pages_scanned = 0;
__free_one_page(page, zone, order, migratetype);
__free_one_page(page, pfn, zone, order, migratetype);
if (unlikely(!is_migrate_isolate(migratetype)))
__mod_zone_freepage_state(zone, 1 << order, migratetype);
spin_unlock(&zone->lock);
@ -766,15 +769,16 @@ static void __free_pages_ok(struct page *page, unsigned int order)
{
unsigned long flags;
int migratetype;
unsigned long pfn = page_to_pfn(page);
if (!free_pages_prepare(page, order))
return;
local_irq_save(flags);
__count_vm_events(PGFREE, 1 << order);
migratetype = get_pageblock_migratetype(page);
migratetype = get_pfnblock_migratetype(page, pfn);
set_freepage_migratetype(page, migratetype);
free_one_page(page_zone(page), page, order, migratetype);
free_one_page(page_zone(page), page, pfn, order, migratetype);
local_irq_restore(flags);
}
@ -1380,12 +1384,13 @@ void free_hot_cold_page(struct page *page, int cold)
struct zone *zone = page_zone(page);
struct per_cpu_pages *pcp;
unsigned long flags;
unsigned long pfn = page_to_pfn(page);
int migratetype;
if (!free_pages_prepare(page, 0))
return;
migratetype = get_pageblock_migratetype(page);
migratetype = get_pfnblock_migratetype(page, pfn);
set_freepage_migratetype(page, migratetype);
local_irq_save(flags);
__count_vm_event(PGFREE);
@ -1399,7 +1404,7 @@ void free_hot_cold_page(struct page *page, int cold)
*/
if (migratetype >= MIGRATE_PCPTYPES) {
if (unlikely(is_migrate_isolate(migratetype))) {
free_one_page(zone, page, 0, migratetype);
free_one_page(zone, page, pfn, 0, migratetype);
goto out;
}
migratetype = MIGRATE_MOVABLE;
@ -6028,17 +6033,16 @@ static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
* @end_bitidx: The last bit of interest
* returns pageblock_bits flags
*/
unsigned long get_pageblock_flags_mask(struct page *page,
unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
unsigned long end_bitidx,
unsigned long mask)
{
struct zone *zone;
unsigned long *bitmap;
unsigned long pfn, bitidx, word_bitidx;
unsigned long bitidx, word_bitidx;
unsigned long word;
zone = page_zone(page);
pfn = page_to_pfn(page);
bitmap = get_pageblock_bitmap(zone, pfn);
bitidx = pfn_to_bitidx(zone, pfn);
word_bitidx = bitidx / BITS_PER_LONG;
@ -6050,25 +6054,25 @@ unsigned long get_pageblock_flags_mask(struct page *page,
}
/**
* set_pageblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
* set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
* @page: The page within the block of interest
* @start_bitidx: The first bit of interest
* @end_bitidx: The last bit of interest
* @flags: The flags to set
*/
void set_pageblock_flags_mask(struct page *page, unsigned long flags,
void set_pfnblock_flags_mask(struct page *page, unsigned long flags,
unsigned long pfn,
unsigned long end_bitidx,
unsigned long mask)
{
struct zone *zone;
unsigned long *bitmap;
unsigned long pfn, bitidx, word_bitidx;
unsigned long bitidx, word_bitidx;
unsigned long old_word, word;
BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4);
zone = page_zone(page);
pfn = page_to_pfn(page);
bitmap = get_pageblock_bitmap(zone, pfn);
bitidx = pfn_to_bitidx(zone, pfn);
word_bitidx = bitidx / BITS_PER_LONG;