From patchwork Wed Jan 3 09:14:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 13509800 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4A71BC3DA6E for ; Wed, 3 Jan 2024 09:15:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OjJM2Tk+EWVH4iUf1B1/zQkh70xvIc7xwYCq9oh1X78=; b=n/drktI6zhcgXG Wv6CYqjowaczatWSiA8Kd5f1fjIkIyAxbaoCa9boQGMTdSjS1daP4wt7uyyHzvhelERgGvHlOO3hp sHqOlBfCsOG9V607FVqsshSUBkyJfyMTAV7iSkAVgZKKPN5FzPlK8Pecqxry+z/t2teGByxvdkLte 9jEJsehDOI0ShURgJw+73rdL6CMoJOPxl0pCEixL7iR8vPO/sRklg8/GjDHqZUyQyhasJGlzDaH58 IKd+e39+xgxQ5vPkTUQxVyjtDUnppbOALbdeWbhIpR4G1YWYPyGFL+KjkiAVEy+z7rOfq9OibiN4l WeR76RIqqI8crMLMfUrw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rKxLq-00ABQ3-0V; Wed, 03 Jan 2024 09:15:50 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rKxLn-00ABNH-0v for linux-riscv@lists.infradead.org; Wed, 03 Jan 2024 09:15:48 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1704273346; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GERLJEPmXyjsod6a3w+H+MRPlzFy0pZTus1RG/9onmU=; b=FFul2ySqpE6xkzSg/+G+C/t/Dpvzh0PsRrxGGHXH6WniIrNrKsssifqsMnyQeXoJrPFgMO zTuRv4YsxPEYB2ae51xaSgdESVAP/K0B9xRo/JsMPSsILxGoQy0iIEHAbSVoqF/6PMESC0 BJIvu9HYZ60C/iUg4IjjdpPt1evMu2I= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-621-AvRlxFvDMHWmUtn2K9LV5Q-1; Wed, 03 Jan 2024 04:15:42 -0500 X-MC-Unique: AvRlxFvDMHWmUtn2K9LV5Q-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1957D29AA38F; Wed, 3 Jan 2024 09:15:41 +0000 (UTC) Received: from x1n.redhat.com (unknown [10.72.116.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7C3DE492BE6; Wed, 3 Jan 2024 09:15:29 +0000 (UTC) From: peterx@redhat.com To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: James Houghton , David Hildenbrand , "Kirill A . Shutemov" , Yang Shi , peterx@redhat.com, linux-riscv@lists.infradead.org, Andrew Morton , "Aneesh Kumar K . V" , Rik van Riel , Andrea Arcangeli , Axel Rasmussen , Mike Rapoport , John Hubbard , Vlastimil Babka , Michael Ellerman , Christophe Leroy , Andrew Jones , linuxppc-dev@lists.ozlabs.org, Mike Kravetz , Muchun Song , linux-arm-kernel@lists.infradead.org, Jason Gunthorpe , Christoph Hellwig , Lorenzo Stoakes , Matthew Wilcox Subject: [PATCH v2 05/13] mm: Introduce vma_pgtable_walk_{begin|end}() Date: Wed, 3 Jan 2024 17:14:15 +0800 Message-ID: <20240103091423.400294-6-peterx@redhat.com> In-Reply-To: <20240103091423.400294-1-peterx@redhat.com> References: <20240103091423.400294-1-peterx@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240103_011547_403969_CB03B314 X-CRM114-Status: GOOD ( 11.80 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Peter Xu Introduce per-vma begin()/end() helpers for pgtable walks. This is a preparation work to merge hugetlb pgtable walkers with generic mm. The helpers need to be called before and after a pgtable walk, will start to be needed if the pgtable walker code supports hugetlb pages. It's a hook point for any type of VMA, but for now only hugetlb uses it to stablize the pgtable pages from getting away (due to possible pmd unsharing). Reviewed-by: Christoph Hellwig Reviewed-by: Muchun Song Signed-off-by: Peter Xu --- include/linux/mm.h | 3 +++ mm/memory.c | 12 ++++++++++++ 2 files changed, 15 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 896c0079f64f..6836da00671a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -4181,4 +4181,7 @@ static inline bool pfn_is_unaccepted_memory(unsigned long pfn) return range_contains_unaccepted_memory(paddr, paddr + PAGE_SIZE); } +void vma_pgtable_walk_begin(struct vm_area_struct *vma); +void vma_pgtable_walk_end(struct vm_area_struct *vma); + #endif /* _LINUX_MM_H */ diff --git a/mm/memory.c b/mm/memory.c index 7e1f4849463a..89f3caac2ec8 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -6279,3 +6279,15 @@ void ptlock_free(struct ptdesc *ptdesc) kmem_cache_free(page_ptl_cachep, ptdesc->ptl); } #endif + +void vma_pgtable_walk_begin(struct vm_area_struct *vma) +{ + if (is_vm_hugetlb_page(vma)) + hugetlb_vma_lock_read(vma); +} + +void vma_pgtable_walk_end(struct vm_area_struct *vma) +{ + if (is_vm_hugetlb_page(vma)) + hugetlb_vma_unlock_read(vma); +}