From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753653AbcD0MB3 (ORCPT ); Wed, 27 Apr 2016 08:01:29 -0400 Received: from mx2.suse.de ([195.135.220.15]:51466 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752517AbcD0MB0 (ORCPT ); Wed, 27 Apr 2016 08:01:26 -0400 From: Vlastimil Babka To: Mel Gorman , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jesper Dangaard Brouer , 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> X-Mailer: git-send-email 2.8.1 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: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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