From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id 3AF9D6B02BC for ; Tue, 6 Nov 2018 01:03:36 -0500 (EST) Received: by mail-pf1-f198.google.com with SMTP id b15-v6so7070269pfo.3 for ; Mon, 05 Nov 2018 22:03:36 -0800 (PST) Received: from alexa-out-blr-01.qualcomm.com (alexa-out-blr-01.qualcomm.com. [103.229.18.197]) by mx.google.com with ESMTPS id y27si11829553pga.459.2018.11.05.22.03.34 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 05 Nov 2018 22:03:35 -0800 (PST) From: Arun KS Subject: [PATCH v6 2/2] mm/page_alloc: remove software prefetching in __free_pages_core Date: Tue, 6 Nov 2018 11:33:14 +0530 Message-Id: <1541484194-1493-2-git-send-email-arunks@codeaurora.org> In-Reply-To: <1541484194-1493-1-git-send-email-arunks@codeaurora.org> References: <1541484194-1493-1-git-send-email-arunks@codeaurora.org> Sender: owner-linux-mm@kvack.org List-ID: To: arunks.linux@gmail.com, akpm@linux-foundation.org, mhocko@kernel.org, vbabka@suse.cz, osalvador@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: getarunks@gmail.com, Arun KS They not only increase the code footprint, they actually make things slower rather than faster. Remove them as contemporary hardware doesn't need any hint. Suggested-by: Dan Williams Signed-off-by: Arun KS --- mm/page_alloc.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 7cf503f..a1b9a6a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1270,14 +1270,10 @@ void __free_pages_core(struct page *page, unsigned int order) struct page *p = page; unsigned int loop; - prefetchw(p); - for (loop = 0; loop < (nr_pages - 1); loop++, p++) { - prefetchw(p + 1); + for (loop = 0; loop < nr_pages ; loop++, p++) { __ClearPageReserved(p); set_page_count(p, 0); } - __ClearPageReserved(p); - set_page_count(p, 0); page_zone(page)->managed_pages += nr_pages; set_page_refcounted(page); -- 1.9.1