| From dhobsong@igel.co.jp Mon Oct 29 00:51:51 2012 |
| From: Damian Hobson-Garcia <dhobsong@igel.co.jp> |
| Date: Mon, 29 Oct 2012 16:50:19 +0900 |
| Subject: [PATCH v2 02/58] mm: compaction: introduce isolate_migratepages_range() |
| To: greg@kroah.com, laurent.pinchart@ideasonboard.com, horms@verge.net.au |
| Cc: ltsi-dev@lists.linuxfoundation.org, dhobsong@igel.co.jp |
| Message-ID: <1351497075-32717-3-git-send-email-dhobsong@igel.co.jp> |
| |
| |
| From: Michal Nazarewicz <mina86@mina86.com> |
| |
| This commit introduces isolate_migratepages_range() function which |
| extracts functionality from isolate_migratepages() so that it can be |
| used on arbitrary PFN ranges. |
| |
| isolate_migratepages() function is implemented as a simple wrapper |
| around isolate_migratepages_range(). |
| |
| 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> |
| (cherry picked from commit 2fe86e0004076128f05d5a774b5c9c03d9dc3de2) |
| |
| Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp> |
| Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> |
| --- |
| mm/compaction.c | 75 +++++++++++++++++++++++++++++++++++++++--------------- |
| 1 files changed, 54 insertions(+), 21 deletions(-) |
| |
| diff --git a/mm/compaction.c b/mm/compaction.c |
| index 459b0ab..0304ff6 100644 |
| --- a/mm/compaction.c |
| +++ b/mm/compaction.c |
| @@ -250,31 +250,34 @@ typedef enum { |
| ISOLATE_SUCCESS, /* Pages isolated, migrate */ |
| } isolate_migrate_t; |
| |
| -/* |
| - * Isolate all pages that can be migrated from the block pointed to by |
| - * the migrate scanner within compact_control. |
| +/** |
| + * isolate_migratepages_range() - isolate all migrate-able pages in range. |
| + * @zone: Zone pages are in. |
| + * @cc: Compaction control structure. |
| + * @low_pfn: The first PFN of the range. |
| + * @end_pfn: The one-past-the-last PFN of the range. |
| + * |
| + * Isolate all pages that can be migrated from the range specified by |
| + * [low_pfn, end_pfn). Returns zero if there is a fatal signal |
| + * pending), otherwise PFN of the first page that was not scanned |
| + * (which may be both less, equal to or more then end_pfn). |
| + * |
| + * Assumes that cc->migratepages is empty and cc->nr_migratepages is |
| + * zero. |
| + * |
| + * Apart from cc->migratepages and cc->nr_migratetypes this function |
| + * does not modify any cc's fields, in particular it does not modify |
| + * (or read for that matter) cc->migrate_pfn. |
| */ |
| -static isolate_migrate_t isolate_migratepages(struct zone *zone, |
| - struct compact_control *cc) |
| +static unsigned long |
| +isolate_migratepages_range(struct zone *zone, struct compact_control *cc, |
| + unsigned long low_pfn, unsigned long end_pfn) |
| { |
| - unsigned long low_pfn, end_pfn; |
| unsigned long last_pageblock_nr = 0, pageblock_nr; |
| unsigned long nr_scanned = 0, nr_isolated = 0; |
| struct list_head *migratelist = &cc->migratepages; |
| isolate_mode_t mode = ISOLATE_ACTIVE|ISOLATE_INACTIVE; |
| |
| - /* Do not scan outside zone boundaries */ |
| - low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn); |
| - |
| - /* Only scan within a pageblock boundary */ |
| - end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages); |
| - |
| - /* Do not cross the free scanner or scan within a memory hole */ |
| - if (end_pfn > cc->free_pfn || !pfn_valid(low_pfn)) { |
| - cc->migrate_pfn = end_pfn; |
| - return ISOLATE_NONE; |
| - } |
| - |
| /* |
| * Ensure that there are not too many pages isolated from the LRU |
| * list by either parallel reclaimers or compaction. If there are, |
| @@ -283,12 +286,12 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone, |
| while (unlikely(too_many_isolated(zone))) { |
| /* async migration should just abort */ |
| if (!cc->sync) |
| - return ISOLATE_ABORT; |
| + return 0; |
| |
| congestion_wait(BLK_RW_ASYNC, HZ/10); |
| |
| if (fatal_signal_pending(current)) |
| - return ISOLATE_ABORT; |
| + return 0; |
| } |
| |
| /* Time to isolate some pages for migration */ |
| @@ -396,10 +399,40 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone, |
| acct_isolated(zone, cc); |
| |
| spin_unlock_irq(&zone->lru_lock); |
| - cc->migrate_pfn = low_pfn; |
| |
| trace_mm_compaction_isolate_migratepages(nr_scanned, nr_isolated); |
| |
| + return low_pfn; |
| +} |
| + |
| +/* |
| + * Isolate all pages that can be migrated from the block pointed to by |
| + * the migrate scanner within compact_control. |
| + */ |
| +static isolate_migrate_t isolate_migratepages(struct zone *zone, |
| + struct compact_control *cc) |
| +{ |
| + unsigned long low_pfn, end_pfn; |
| + |
| + /* Do not scan outside zone boundaries */ |
| + low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn); |
| + |
| + /* Only scan within a pageblock boundary */ |
| + end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages); |
| + |
| + /* Do not cross the free scanner or scan within a memory hole */ |
| + if (end_pfn > cc->free_pfn || !pfn_valid(low_pfn)) { |
| + cc->migrate_pfn = end_pfn; |
| + return ISOLATE_NONE; |
| + } |
| + |
| + /* Perform the isolation */ |
| + low_pfn = isolate_migratepages_range(zone, cc, low_pfn, end_pfn); |
| + if (!low_pfn) |
| + return ISOLATE_ABORT; |
| + |
| + cc->migrate_pfn = low_pfn; |
| + |
| return ISOLATE_SUCCESS; |
| } |
| |
| -- |
| 1.7.5.4 |
| |