From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754002Ab2BCMTH (ORCPT ); Fri, 3 Feb 2012 07:19:07 -0500 Received: from mailout3.w1.samsung.com ([210.118.77.13]:14440 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425Ab2BCMTE (ORCPT ); Fri, 3 Feb 2012 07:19:04 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: TEXT/PLAIN Date: Fri, 03 Feb 2012 13:18:45 +0100 From: Marek Szyprowski Subject: [PATCH 02/15] mm: compaction: introduce isolate_migratepages_range(). In-reply-to: <1328271538-14502-1-git-send-email-m.szyprowski@samsung.com> To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org Cc: Michal Nazarewicz , Marek Szyprowski , Kyungmin Park , Russell King , Andrew Morton , KAMEZAWA Hiroyuki , Daniel Walker , Mel Gorman , Arnd Bergmann , Jesse Barker , Jonathan Corbet , Shariq Hasnain , Chunsang Jeong , Dave Hansen , Benjamin Gaignard , Rob Clark , Ohad Ben-Cohen Message-id: <1328271538-14502-3-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.7.7.3 References: <1328271538-14502-1-git-send-email-m.szyprowski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Nazarewicz 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 Signed-off-by: Marek Szyprowski Acked-by: Mel Gorman Tested-by: Rob Clark Tested-by: Ohad Ben-Cohen Tested-by: Benjamin Gaignard --- mm/compaction.c | 75 +++++++++++++++++++++++++++++++++++++++--------------- 1 files changed, 54 insertions(+), 21 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index 71a58f6..62902b6 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 */ @@ -374,10 +377,40 @@ 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; } -- 1.7.1.569.g6f426