From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1610C001B3 for ; Tue, 27 Jun 2023 08:09:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 66A9E8D0003; Tue, 27 Jun 2023 04:09:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 61AE78D0001; Tue, 27 Jun 2023 04:09:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 50A468D0003; Tue, 27 Jun 2023 04:09:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 44C5F8D0001 for ; Tue, 27 Jun 2023 04:09:41 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 1CECD1C8884 for ; Tue, 27 Jun 2023 08:09:41 +0000 (UTC) X-FDA: 80947803762.06.C1E9A1C Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf08.hostedemail.com (Postfix) with ESMTP id 5276D160004 for ; Tue, 27 Jun 2023 08:09:38 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf08.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1687853378; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cpYIl3ybeD9J1jn4Ho0JrCxBglHFM/q0BHoK7jZMHPg=; b=seHoExWwJBihOEDJK/Hg0Wz0dMS0STl4+yADVJHO5To9kmmdDYcWeI9Ak6Ncg2OLiktNaE M2uwTSgnAgitlWow/N/h39v+FaiDKh10dk/S9Pduoy3teAzXtwunWuDxrqzTNvTdNPXral tRsO+gAROd8c9+Lw5LGLzTAk518e6Ig= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf08.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1687853378; a=rsa-sha256; cv=none; b=AIJpd8pauO1eVrNTZcBurpbdlecuKxlkTTJQ1uTTkW0WyC64N72znN8V/Lp/5WGsSlsmx0 YP2jWjASurspAV+b0/v/lqqtMvltplRP17Y/4QxMYNE502NfpLZJ5RJrvP7P/IkyFDAHpw b+lgTVx4kxWGzcwhpcmmq5jIyQMI4Bg= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7400B2F4; Tue, 27 Jun 2023 01:10:21 -0700 (PDT) Received: from [10.57.76.16] (unknown [10.57.76.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 780303F663; Tue, 27 Jun 2023 01:09:33 -0700 (PDT) Message-ID: Date: Tue, 27 Jun 2023 09:09:31 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Subject: Re: [PATCH v1 04/10] mm: Implement folio_add_new_anon_rmap_range() To: Yu Zhao Cc: Andrew Morton , "Matthew Wilcox (Oracle)" , "Kirill A. Shutemov" , Yin Fengwei , David Hildenbrand , Catalin Marinas , Will Deacon , Geert Uytterhoeven , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-s390@vger.kernel.org References: <20230626171430.3167004-1-ryan.roberts@arm.com> <20230626171430.3167004-5-ryan.roberts@arm.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 5276D160004 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: p4ewjmz3mwed494xzfxo73yaio3t31sn X-HE-Tag: 1687853378-266141 X-HE-Meta: U2FsdGVkX19/adYCBsIc1P3U723SUw0taxNobgfb9+GukjkrhUzXMQrlKHI24hiQuwAT5bOJmCDvEkgcSwVgfmPzmylTpG4pf4bvE9oORfC4wmLyRNCfRMTe0MOdbZPD6QmEz2HqXYkTDZ0+5kCcq+tpXkfsMHZwN7uoqMVBJqLaSm/PKZ+jSueNJvrUXisKyY0tHEiR7jLUTqaHh/R8nSPc1jIFMh4UdwHkh2BvF0eU8u0WrSUlUlsjwbDznFf00jW5muUvxL/EeWRz4FEtjQ6lxLsNgwalJEdNxwM+p3MNrIJllOpbzjG64BRzXjrlkGOGC97OoJDCYOKwO9I97j/qjFiphgc9xDl3eGy76vWQUbS0IK1fjij9o8nd56FhZy3OFQ9DfobXRJJWtz4aeMqzHEIk1OUMJJ0T7ayt2RVgS6b3oZdn7GbQmmGMiCFj1q7oYVJonb33kB/fA+Rp0ERRy3C6CuavDelzfCwzXMD68xDKrIMXYa/HyYmDJO9viKVHvuw7srJB+N2ooNOC2EL8DdF6BcQcGV68DMHxG9BeoBx898yeHf8S6HnXthA54NnEXL86p/65Q0naCNPhvDhWUi9U132I95Wha/LB53tIiofqF+yJ4VVBVsLdVFPE+G1I5fe/x1WumaRvDXNeEj6RukV0jYfSZhShi06CMI4Xkvg8GCDnarsbdvNDM/PW5dHL7Wl8M5LsFiOQgpzciAJPj41bIHXyAidl2Rl7GsQ87Qc0kSWsqoqQ3m/VLaAqtaa8s9aY0n2yu3XU039tN6kEy6CU3HMsuVEZaKG99p92hKvvJhe6ZnBgV2x7Ws7zPUQ4xeNFBhqw1nCaxhDdDZf1n/48avm+OuSZJKGKHRpN31Njto5MiZdk0ipmtMD3c3ODc0ApoD3HGgGq1zPDpj/YUNg0gyZaCzr1UWzgO7Ly/ljjcy0CHJ+AAdtCi619x3Hy4O1yI5Szm+rDSWc QMmhrtrY sMnhsItYvW/FhIZswgJqRZSkATafA/9FKtJXaOsLUsA5bpC2FUngzfn0BtR2TCj16/ifcpUwHMqCTqUoVLVHXEe9dBuvFktdtEylRpSwhzwNSfZbhDgDSgk1Bn3AaOn2ohfPe2o+ry0ZF/c1V9Bws3FWdddArIYHeb6v46lVU7h6FyfXCmq7eFcORL5tsFzwNk6jBIRus0BCr8abcrkIT1evBIIWZifSUXHWJPXnaugWcRMqdeg8j3fG3QUWpDniY8CuHDJtjlDvTGU0CycBqOwZ9iXuvZ1DA21E5YajYKhtnYTHtHNu0MLCpYKL6TkAgtPazXxD3WKeiKngCwKsLwrI4Rw== 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: On 27/06/2023 08:08, Yu Zhao wrote: > On Mon, Jun 26, 2023 at 11:14 AM Ryan Roberts wrote: >> >> Like folio_add_new_anon_rmap() but batch-rmaps a range of pages >> belonging to a folio, for effciency savings. All pages are accounted as >> small pages. >> >> Signed-off-by: Ryan Roberts >> --- >> include/linux/rmap.h | 2 ++ >> mm/rmap.c | 43 +++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 45 insertions(+) >> >> diff --git a/include/linux/rmap.h b/include/linux/rmap.h >> index a3825ce81102..15433a3d0cbf 100644 >> --- a/include/linux/rmap.h >> +++ b/include/linux/rmap.h >> @@ -196,6 +196,8 @@ void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, >> unsigned long address); >> void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, >> unsigned long address); >> +void folio_add_new_anon_rmap_range(struct folio *folio, struct page *page, >> + int nr, struct vm_area_struct *vma, unsigned long address); > > We should update folio_add_new_anon_rmap() to support large() && > !folio_test_pmd_mappable() folios instead. > > I double checked all places currently using folio_add_new_anon_rmap(), > and as expected, none actually allocates large() && > !folio_test_pmd_mappable() and maps it one by one, which makes the > cases simpler, i.e., > if (!large()) > // the existing basepage case > else if (!folio_test_pmd_mappable()) > // our new case > else > // the existing THP case I don't have a strong opinion either way. Happy to go with this suggestion. But the reason I did it as a new function was because I was following the pattern in [1] which adds a new folio_add_file_rmap_range() function. [1] https://lore.kernel.org/linux-mm/20230315051444.3229621-35-willy@infradead.org/ > >> void page_add_file_rmap(struct page *, struct vm_area_struct *, >> bool compound); >> void folio_add_file_rmap_range(struct folio *, struct page *, unsigned int nr, >> diff --git a/mm/rmap.c b/mm/rmap.c >> index 1d8369549424..4050bcea7ae7 100644 >> --- a/mm/rmap.c >> +++ b/mm/rmap.c >> @@ -1305,6 +1305,49 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, >> __page_set_anon_rmap(folio, &folio->page, vma, address, 1); >> } >> >> +/** >> + * folio_add_new_anon_rmap_range - Add mapping to a set of pages within a new >> + * anonymous potentially large folio. >> + * @folio: The folio containing the pages to be mapped >> + * @page: First page in the folio to be mapped >> + * @nr: Number of pages to be mapped >> + * @vma: the vm area in which the mapping is added >> + * @address: the user virtual address of the first page to be mapped >> + * >> + * Like folio_add_new_anon_rmap() but batch-maps a range of pages within a folio >> + * using non-THP accounting. Like folio_add_new_anon_rmap(), the inc-and-test is >> + * bypassed and the folio does not have to be locked. All pages in the folio are >> + * individually accounted. >> + * >> + * As the folio is new, it's assumed to be mapped exclusively by a single >> + * process. >> + */ >> +void folio_add_new_anon_rmap_range(struct folio *folio, struct page *page, >> + int nr, struct vm_area_struct *vma, unsigned long address) >> +{ >> + int i; >> + >> + VM_BUG_ON_VMA(address < vma->vm_start || >> + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); > > BTW, VM_BUG_ON* shouldn't be used in new code: > Documentation/process/coding-style.rst Thanks, sorry about that. Was copy-pasting from folio_add_new_anon_rmap().