mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-10-31 18:09:19 +00:00
mm: compaction: introduce isolate_freepages_range()
This commit introduces isolate_freepages_range() function which generalises isolate_freepages_block() so that it can be used on arbitrary PFN ranges. isolate_freepages_block() is left with only minor changes. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Tested-by: Rob Clark <rob.clark@linaro.org> Tested-by: Ohad Ben-Cohen <ohad@wizery.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Tested-by: Robert Nelson <robertcnelson@gmail.com> Tested-by: Barry Song <Baohua.Song@csr.com>
This commit is contained in:
parent
03d44192f6
commit
85aa125f00
1 changed files with 93 additions and 18 deletions
111
mm/compaction.c
111
mm/compaction.c
|
@ -54,24 +54,20 @@ static unsigned long release_freepages(struct list_head *freelist)
|
|||
return count;
|
||||
}
|
||||
|
||||
/* Isolate free pages onto a private freelist. Must hold zone->lock */
|
||||
static unsigned long isolate_freepages_block(struct zone *zone,
|
||||
unsigned long blockpfn,
|
||||
struct list_head *freelist)
|
||||
/*
|
||||
* Isolate free pages onto a private freelist. Caller must hold zone->lock.
|
||||
* If @strict is true, will abort returning 0 on any invalid PFNs or non-free
|
||||
* pages inside of the pageblock (even though it may still end up isolating
|
||||
* some pages).
|
||||
*/
|
||||
static unsigned long isolate_freepages_block(unsigned long blockpfn,
|
||||
unsigned long end_pfn,
|
||||
struct list_head *freelist,
|
||||
bool strict)
|
||||
{
|
||||
unsigned long zone_end_pfn, end_pfn;
|
||||
int nr_scanned = 0, total_isolated = 0;
|
||||
struct page *cursor;
|
||||
|
||||
/* Get the last PFN we should scan for free pages at */
|
||||
zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
|
||||
end_pfn = min(blockpfn + pageblock_nr_pages, zone_end_pfn);
|
||||
|
||||
/* Find the first usable PFN in the block to initialse page cursor */
|
||||
for (; blockpfn < end_pfn; blockpfn++) {
|
||||
if (pfn_valid_within(blockpfn))
|
||||
break;
|
||||
}
|
||||
cursor = pfn_to_page(blockpfn);
|
||||
|
||||
/* Isolate free pages. This assumes the block is valid */
|
||||
|
@ -79,15 +75,23 @@ static unsigned long isolate_freepages_block(struct zone *zone,
|
|||
int isolated, i;
|
||||
struct page *page = cursor;
|
||||
|
||||
if (!pfn_valid_within(blockpfn))
|
||||
if (!pfn_valid_within(blockpfn)) {
|
||||
if (strict)
|
||||
return 0;
|
||||
continue;
|
||||
}
|
||||
nr_scanned++;
|
||||
|
||||
if (!PageBuddy(page))
|
||||
if (!PageBuddy(page)) {
|
||||
if (strict)
|
||||
return 0;
|
||||
continue;
|
||||
}
|
||||
|
||||
/* Found a free page, break it into order-0 pages */
|
||||
isolated = split_free_page(page);
|
||||
if (!isolated && strict)
|
||||
return 0;
|
||||
total_isolated += isolated;
|
||||
for (i = 0; i < isolated; i++) {
|
||||
list_add(&page->lru, freelist);
|
||||
|
@ -105,6 +109,73 @@ static unsigned long isolate_freepages_block(struct zone *zone,
|
|||
return total_isolated;
|
||||
}
|
||||
|
||||
/**
|
||||
* isolate_freepages_range() - isolate free pages.
|
||||
* @start_pfn: The first PFN to start isolating.
|
||||
* @end_pfn: The one-past-last PFN.
|
||||
*
|
||||
* Non-free pages, invalid PFNs, or zone boundaries within the
|
||||
* [start_pfn, end_pfn) range are considered errors, cause function to
|
||||
* undo its actions and return zero.
|
||||
*
|
||||
* Otherwise, function returns one-past-the-last PFN of isolated page
|
||||
* (which may be greater then end_pfn if end fell in a middle of
|
||||
* a free page).
|
||||
*/
|
||||
static unsigned long
|
||||
isolate_freepages_range(unsigned long start_pfn, unsigned long end_pfn)
|
||||
{
|
||||
unsigned long isolated, pfn, block_end_pfn, flags;
|
||||
struct zone *zone = NULL;
|
||||
LIST_HEAD(freelist);
|
||||
|
||||
if (pfn_valid(start_pfn))
|
||||
zone = page_zone(pfn_to_page(start_pfn));
|
||||
|
||||
for (pfn = start_pfn; pfn < end_pfn; pfn += isolated) {
|
||||
if (!pfn_valid(pfn) || zone != page_zone(pfn_to_page(pfn)))
|
||||
break;
|
||||
|
||||
/*
|
||||
* On subsequent iterations ALIGN() is actually not needed,
|
||||
* but we keep it that we not to complicate the code.
|
||||
*/
|
||||
block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
|
||||
block_end_pfn = min(block_end_pfn, end_pfn);
|
||||
|
||||
spin_lock_irqsave(&zone->lock, flags);
|
||||
isolated = isolate_freepages_block(pfn, block_end_pfn,
|
||||
&freelist, true);
|
||||
spin_unlock_irqrestore(&zone->lock, flags);
|
||||
|
||||
/*
|
||||
* In strict mode, isolate_freepages_block() returns 0 if
|
||||
* there are any holes in the block (ie. invalid PFNs or
|
||||
* non-free pages).
|
||||
*/
|
||||
if (!isolated)
|
||||
break;
|
||||
|
||||
/*
|
||||
* If we managed to isolate pages, it is always (1 << n) *
|
||||
* pageblock_nr_pages for some non-negative n. (Max order
|
||||
* page may span two pageblocks).
|
||||
*/
|
||||
}
|
||||
|
||||
/* split_free_page does not map the pages */
|
||||
map_pages(&freelist);
|
||||
|
||||
if (pfn < end_pfn) {
|
||||
/* Loop terminated early, cleanup. */
|
||||
release_freepages(&freelist);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* We don't use freelists for anything. */
|
||||
return pfn;
|
||||
}
|
||||
|
||||
/* Returns true if the page is within a block suitable for migration to */
|
||||
static bool suitable_migration_target(struct page *page)
|
||||
{
|
||||
|
@ -145,7 +216,7 @@ static void isolate_freepages(struct zone *zone,
|
|||
struct compact_control *cc)
|
||||
{
|
||||
struct page *page;
|
||||
unsigned long high_pfn, low_pfn, pfn;
|
||||
unsigned long high_pfn, low_pfn, pfn, zone_end_pfn, end_pfn;
|
||||
unsigned long flags;
|
||||
int nr_freepages = cc->nr_freepages;
|
||||
struct list_head *freelist = &cc->freepages;
|
||||
|
@ -165,6 +236,8 @@ static void isolate_freepages(struct zone *zone,
|
|||
*/
|
||||
high_pfn = min(low_pfn, pfn);
|
||||
|
||||
zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
|
||||
|
||||
/*
|
||||
* Isolate free pages until enough are available to migrate the
|
||||
* pages on cc->migratepages. We stop searching if the migrate
|
||||
|
@ -201,7 +274,9 @@ static void isolate_freepages(struct zone *zone,
|
|||
isolated = 0;
|
||||
spin_lock_irqsave(&zone->lock, flags);
|
||||
if (suitable_migration_target(page)) {
|
||||
isolated = isolate_freepages_block(zone, pfn, freelist);
|
||||
end_pfn = min(pfn + pageblock_nr_pages, zone_end_pfn);
|
||||
isolated = isolate_freepages_block(pfn, end_pfn,
|
||||
freelist, false);
|
||||
nr_freepages += isolated;
|
||||
}
|
||||
spin_unlock_irqrestore(&zone->lock, flags);
|
||||
|
|
Loading…
Reference in a new issue