From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f71.google.com (mail-wm0-f71.google.com [74.125.82.71]) by kanga.kvack.org (Postfix) with ESMTP id 5D45C6B025F for ; Wed, 27 Apr 2016 10:57:31 -0400 (EDT) Received: by mail-wm0-f71.google.com with SMTP id s63so42389597wme.2 for ; Wed, 27 Apr 2016 07:57:31 -0700 (PDT) Received: from outbound-smtp11.blacknight.com (outbound-smtp11.blacknight.com. [46.22.139.16]) by mx.google.com with ESMTPS id g69si9543069wme.83.2016.04.27.07.57.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Apr 2016 07:57:25 -0700 (PDT) Received: from mail.blacknight.com (pemlinmail03.blacknight.ie [81.17.254.16]) by outbound-smtp11.blacknight.com (Postfix) with ESMTPS id E916E1C15AC for ; Wed, 27 Apr 2016 15:57:24 +0100 (IST) From: Mel Gorman Subject: [PATCH 6/6] mm, page_alloc: don't duplicate code in free_pcp_prepare Date: Wed, 27 Apr 2016 15:57:23 +0100 Message-Id: <1461769043-28337-7-git-send-email-mgorman@techsingularity.net> In-Reply-To: <1461769043-28337-1-git-send-email-mgorman@techsingularity.net> References: <1461769043-28337-1-git-send-email-mgorman@techsingularity.net> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Vlastimil Babka , Jesper Dangaard Brouer , Linux-MM , LKML , Mel Gorman The new free_pcp_prepare() function shares a lot of code with free_pages_prepare(), which makes this a maintenance risk when some future patch modifies only one of them. We should be able to achieve the same effect (skipping free_pages_check() from !DEBUG_VM configs) by adding a parameter to free_pages_prepare() and making it inline, so the checks (and the order != 0 parts) are eliminated from the call from free_pcp_prepare(). !DEBUG_VM: bloat-o-meter reports no difference, as my gcc was already inlining free_pages_prepare() and the elimination seems to work as expected DEBUG_VM bloat-o-meter: add/remove: 0/1 grow/shrink: 2/0 up/down: 1035/-778 (257) function old new delta __free_pages_ok 297 1060 +763 free_hot_cold_page 480 752 +272 free_pages_prepare 778 - -778 Here inlining didn't occur before, and added some code, but it's ok for a debug option. Signed-off-by: Vlastimil Babka Signed-off-by: Mel Gorman --- mm/page_alloc.c | 35 +++++++---------------------------- 1 file changed, 7 insertions(+), 28 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b823f00c275b..bc4160bfb36b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -990,7 +990,8 @@ static int free_tail_pages_check(struct page *head_page, struct page *page) return ret; } -static bool free_pages_prepare(struct page *page, unsigned int order) +static __always_inline bool free_pages_prepare(struct page *page, unsigned int order, + bool check_free) { int bad = 0; @@ -1022,7 +1023,8 @@ static bool free_pages_prepare(struct page *page, unsigned int order) } if (PageAnonHead(page)) page->mapping = NULL; - bad += free_pages_check(page); + if (check_free) + bad += free_pages_check(page); if (bad) return false; @@ -1046,7 +1048,7 @@ static bool free_pages_prepare(struct page *page, unsigned int order) #ifdef CONFIG_DEBUG_VM static inline bool free_pcp_prepare(struct page *page) { - return free_pages_prepare(page, 0); + return free_pages_prepare(page, 0, true); } static inline bool bulkfree_pcp_prepare(struct page *page) @@ -1056,30 +1058,7 @@ static inline bool bulkfree_pcp_prepare(struct page *page) #else static bool free_pcp_prepare(struct page *page) { - VM_BUG_ON_PAGE(PageTail(page), page); - - trace_mm_page_free(page, 0); - kmemcheck_free_shadow(page, 0); - kasan_poison_free_pages(page, 0); - - if (PageAnonHead(page)) - page->mapping = NULL; - - reset_page_owner(page, 0); - - if (!PageHighMem(page)) { - debug_check_no_locks_freed(page_address(page), - PAGE_SIZE); - debug_check_no_obj_freed(page_address(page), - PAGE_SIZE); - } - arch_free_page(page, 0); - kernel_poison_pages(page, 0, 0); - kernel_map_pages(page, 0, 0); - - page_cpupid_reset_last(page); - page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; - return true; + return free_pages_prepare(page, 0, false); } static bool bulkfree_pcp_prepare(struct page *page) @@ -1257,7 +1236,7 @@ static void __free_pages_ok(struct page *page, unsigned int order) int migratetype; unsigned long pfn = page_to_pfn(page); - if (!free_pages_prepare(page, order)) + if (!free_pages_prepare(page, order, true)) return; migratetype = get_pfnblock_migratetype(page, pfn); -- 2.6.4 -- 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