From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f44.google.com (mail-pa0-f44.google.com [209.85.220.44]) by kanga.kvack.org (Postfix) with ESMTP id BD40E6B0070 for ; Tue, 9 Dec 2014 02:53:55 -0500 (EST) Received: by mail-pa0-f44.google.com with SMTP id et14so76604pad.3 for ; Mon, 08 Dec 2014 23:53:55 -0800 (PST) Received: from mailout1.samsung.com (mailout1.samsung.com. [203.254.224.24]) by mx.google.com with ESMTPS id tk10si590869pac.134.2014.12.08.23.53.53 for (version=TLSv1 cipher=RC4-MD5 bits=128/128); Mon, 08 Dec 2014 23:53:54 -0800 (PST) Received: from epcpsbgm1.samsung.com (epcpsbgm1 [203.254.230.26]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NGB00H2Q1XR1SC0@mailout1.samsung.com> for linux-mm@kvack.org; Tue, 09 Dec 2014 16:53:51 +0900 (KST) From: Weijie Yang Subject: [PATCH 3/3] mm: page_alloc: remove redundant set_freepage_migratetype() calls Date: Tue, 09 Dec 2014 15:51:49 +0800 Message-id: <000301d01385$45554a60$cfffdf20$%yang@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=utf-8 Content-transfer-encoding: 7bit Content-language: zh-cn Sender: owner-linux-mm@kvack.org List-ID: To: iamjoonsoo.kim@lge.com Cc: 'Andrew Morton' , mgorman@suse.de, 'Rik van Riel' , vbabka@suse.cz, 'Johannes Weiner' , 'Minchan Kim' , 'Weijie Yang' , linux-kernel@vger.kernel.org, linux-mm@kvack.org The freepage_migratetype is a temporary cached value which represents the free page's pageblock migratetype. Now we use it in two scenarios: 1. Use it as a cached value in page freeing path. This cached value is temporary and non-100% update, which help us decide which pcp freelist and buddy freelist the page should go rather than using get_pfnblock_migratetype() to save some instructions. When there is race between page isolation and free path, we need use additional method to get a accurate value to put the free pages to the correct freelist and get a precise free pages statistics. 2. Use it in page alloc path to update NR_FREE_CMA_PAGES statistics. This patch aims at the scenario 1 and removes two redundant set_freepage_migratetype() calls, which will make sense in the hot path. Signed-off-by: Weijie Yang --- mm/page_alloc.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 616a2c9..99af01a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -775,7 +775,6 @@ static void __free_pages_ok(struct page *page, unsigned int order) migratetype = get_pfnblock_migratetype(page, pfn); local_irq_save(flags); __count_vm_events(PGFREE, 1 << order); - set_freepage_migratetype(page, migratetype); free_one_page(page_zone(page), page, pfn, order, migratetype); local_irq_restore(flags); } @@ -1024,7 +1023,6 @@ int move_freepages(struct zone *zone, order = page_order(page); list_move(&page->lru, &zone->free_area[order].free_list[migratetype]); - set_freepage_migratetype(page, migratetype); page += 1 << order; pages_moved += 1 << order; } -- 1.7.10.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org