From patchwork Tue Apr 7 03:04:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11477207 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D65AD92A for ; Tue, 7 Apr 2020 03:04:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9A0C8208FE for ; Tue, 7 Apr 2020 03:04:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="MoVEnq7p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A0C8208FE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 219618E001D; Mon, 6 Apr 2020 23:04:34 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 1CAEC8E0001; Mon, 6 Apr 2020 23:04:34 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0B8398E001D; Mon, 6 Apr 2020 23:04:34 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id E550E8E0001 for ; Mon, 6 Apr 2020 23:04:33 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id ACCD452AE for ; Tue, 7 Apr 2020 03:04:33 +0000 (UTC) X-FDA: 76679566026.22.fish74_6200aa86ff238 X-Spam-Summary: 2,0,0,c0f4a37aa8a310b8,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:800:960:967:973:988:989:1260:1263:1345:1359:1381:1431:1437:1534:1541:1711:1730:1747:1777:1792:2393:2525:2559:2563:2682:2685:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3352:3865:3866:3871:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4250:4321:5007:6119:6261:6653:7514:7576:7903:8599:8784:8957:9025:9545:9592:10004:10913:11026:11232:11473:11658:11914:12043:12048:12296:12297:12517:12519:12555:12679:12783:12986:13069:13311:13357:13846:14181:14384:14721:14849:21080:21324:21451:21627:21939:21966:21990:30054:30070,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:1,LUA_SUMMARY:none X-HE-Tag: fish74_6200aa86ff238 X-Filterd-Recvd-Size: 2701 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:04:33 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 31A3720936; Tue, 7 Apr 2020 03:04:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586228672; bh=VsPCTMKE5n9W9vzQzBgS/s51v8+oKvVnv30W5n9cFPY=; h=Date:From:To:Subject:In-Reply-To:From; b=MoVEnq7pWR6x8x0x8mA3gH2hniH8vqmXTcD2K0+DLfVXXubEN/s6/pMt9joHh0Dxf kPBahlEocOb/FPjycjLecRnKdLXZQAnvgCk1jQ6GanF+H6T+75/Ts+4xziY9rQUT0q dSxzfCADPNN4LV24zlphxNNkWLXRsTSEp1QKb81Q= Date: Mon, 06 Apr 2020 20:04:31 -0700 From: Andrew Morton To: akpm@linux-foundation.org, aneesh.kumar@linux.vnet.ibm.com, hch@lst.de, kirill.shutemov@linux.intel.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, pankaj.gupta.linux@gmail.com, torvalds@linux-foundation.org, willy@infradead.org Subject: [patch 019/166] include/linux/pagemap.h: optimise find_subpage for !THP Message-ID: <20200407030431.Aua57ze5l%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "Matthew Wilcox (Oracle)" Subject: include/linux/pagemap.h: optimise find_subpage for !THP If THP is disabled, find_subpage() can become a no-op by using hpage_nr_pages() instead of compound_nr(). hpage_nr_pages() embeds a check for PageTail, so we can drop the check here. Link: http://lkml.kernel.org/r/20200318140253.6141-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Kirill A. Shutemov Reviewed-by: Christoph Hellwig Cc: Aneesh Kumar K.V Cc: Pankaj Gupta Signed-off-by: Andrew Morton --- include/linux/pagemap.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/include/linux/pagemap.h~mm-optimise-find_subpage-for-thp +++ a/include/linux/pagemap.h @@ -341,9 +341,7 @@ static inline struct page *find_subpage( if (PageHuge(head)) return head; - VM_BUG_ON_PAGE(PageTail(head), head); - - return head + (index & (compound_nr(head) - 1)); + return head + (index & (hpage_nr_pages(head) - 1)); } struct page *find_get_entry(struct address_space *mapping, pgoff_t offset);