From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f71.google.com (mail-lf0-f71.google.com [209.85.215.71]) by kanga.kvack.org (Postfix) with ESMTP id 998E76B0253 for ; Wed, 27 Apr 2016 08:01:37 -0400 (EDT) Received: by mail-lf0-f71.google.com with SMTP id y84so34822423lfc.3 for ; Wed, 27 Apr 2016 05:01:37 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id n9si4006576wjz.199.2016.04.27.05.01.25 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 27 Apr 2016 05:01:25 -0700 (PDT) From: Vlastimil Babka Subject: [PATCH 2/3] mm, page_alloc: pull out side effects from free_pages_check Date: Wed, 27 Apr 2016 14:01:15 +0200 Message-Id: <1461758476-450-2-git-send-email-vbabka@suse.cz> In-Reply-To: <1461758476-450-1-git-send-email-vbabka@suse.cz> References: <5720A987.7060507@suse.cz> <1461758476-450-1-git-send-email-vbabka@suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jesper Dangaard Brouer , Vlastimil Babka Check without side-effects should be easier to maintain. It also removes the duplicated cpupid and flags reset done in !DEBUG_VM variant of both free_pcp_prepare() and then bulkfree_pcp_prepare(). Finally, it enables the next patch. It shouldn't result in new branches, thanks to inlining of the check. !DEBUG_VM bloat-o-meter: add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-27 (-27) function old new delta __free_pages_ok 748 739 -9 free_pcppages_bulk 1403 1385 -18 DEBUG_VM: add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-28 (-28) function old new delta free_pages_prepare 806 778 -28 Signed-off-by: Vlastimil Babka --- mm/page_alloc.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 12c03a8509a0..163d08ea43f0 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -932,11 +932,8 @@ static void free_pages_check_bad(struct page *page) } static inline int free_pages_check(struct page *page) { - if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE))) { - page_cpupid_reset_last(page); - page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; + if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE))) return 0; - } /* Something has gone sideways, find it */ free_pages_check_bad(page); @@ -1016,12 +1013,22 @@ static bool free_pages_prepare(struct page *page, unsigned int order) for (i = 1; i < (1 << order); i++) { if (compound) bad += free_tail_pages_check(page, page + i); - bad += free_pages_check(page + i); + if (free_pages_check(page + i)) { + bad++; + } else { + page_cpupid_reset_last(page + i); + (page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; + } } } if (PageAnonHead(page)) page->mapping = NULL; - bad += free_pages_check(page); + if (free_pages_check(page)) { + bad++; + } else { + page_cpupid_reset_last(page); + page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; + } if (bad) return false; -- 2.8.1 -- 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