Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753279Ab2FKCHh (ORCPT ); Sun, 10 Jun 2012 22:07:37 -0400 Received: from LGEMRELSE7Q.lge.com ([156.147.1.151]:55910 "EHLO LGEMRELSE7Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752109Ab2FKCHg (ORCPT ); Sun, 10 Jun 2012 22:07:36 -0400 X-AuditID: 9c930197-b7b5dae000004b23-f4-4fd552e45671 From: Minchan Kim To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Minchan Kim , Mel Gorman , Michal Hocko , KAMEZAWA Hiroyuki Subject: [PATCH] mm: clean up __count_immobile_pages Date: Mon, 11 Jun 2012 11:07:22 +0900 Message-Id: <1339380442-1137-1-git-send-email-minchan@kernel.org> X-Mailer: git-send-email 1.7.9.5 X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3214 Lines: 98 __count_immobile_pages naming is rather awkward. This patch clean up the function and add comment. Cc: Mel Gorman Cc: Michal Hocko Cc: KAMEZAWA Hiroyuki Signed-off-by: Minchan Kim --- mm/page_alloc.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 019c4fe..2c71ac9 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5467,26 +5467,27 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags, } /* - * This is designed as sub function...plz see page_isolation.c also. - * set/clear page block's type to be ISOLATE. - * page allocater never alloc memory from ISOLATE block. + * This function checks whether pageblock includes unmovable pages or not. + * If @count is not zero, it is okay to include less @count unmovable pages + * + * This function can race in PageLRU and MIGRATE_MOVABLE can have unmovable + * pages so that it might be not exact. */ - -static int -__count_immobile_pages(struct zone *zone, struct page *page, int count) +static bool +__has_unmovable_pages(struct zone *zone, struct page *page, int count) { unsigned long pfn, iter, found; int mt; /* * For avoiding noise data, lru_add_drain_all() should be called - * If ZONE_MOVABLE, the zone never contains immobile pages + * If ZONE_MOVABLE, the zone never contains unmovable pages */ if (zone_idx(zone) == ZONE_MOVABLE) - return true; + return false; mt = get_pageblock_migratetype(page); if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt)) - return true; + return false; pfn = page_to_pfn(page); for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) { @@ -5521,9 +5522,9 @@ __count_immobile_pages(struct zone *zone, struct page *page, int count) * page at boot. */ if (found > count) - return false; + return true; } - return true; + return false; } bool is_pageblock_removable_nolock(struct page *page) @@ -5547,7 +5548,7 @@ bool is_pageblock_removable_nolock(struct page *page) zone->zone_start_pfn + zone->spanned_pages <= pfn) return false; - return __count_immobile_pages(zone, page, 0); + return !__has_unmovable_pages(zone, page, 0); } int set_migratetype_isolate(struct page *page) @@ -5586,12 +5587,12 @@ int set_migratetype_isolate(struct page *page) * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself. * We just check MOVABLE pages. */ - if (__count_immobile_pages(zone, page, arg.pages_found)) + if (!__has_unmovable_pages(zone, page, arg.pages_found)) ret = 0; - /* - * immobile means "not-on-lru" paes. If immobile is larger than - * removable-by-driver pages reported by notifier, we'll fail. + * Unmovable means "not-on-lru" pages. If Unmovable pages are + * larger than removable-by-driver pages reported by notifier, + * we'll fail. */ out: -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/