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 X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AA5F1C43460 for ; Fri, 30 Apr 2021 19:53:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90B2F61477 for ; Fri, 30 Apr 2021 19:53:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233635AbhD3Tx4 (ORCPT ); Fri, 30 Apr 2021 15:53:56 -0400 Received: from server.lespinasse.org ([63.205.204.226]:47601 "EHLO server.lespinasse.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232323AbhD3TxY (ORCPT ); Fri, 30 Apr 2021 15:53:24 -0400 DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=lespinasse.org; i=@lespinasse.org; q=dns/txt; s=srv-14-ed; t=1619812353; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : from; bh=BLfb3AqVSS1iZWKnBAI32as/v1HrLIIvwM3hMYePNUI=; b=8cMpbIOWRRdLq4qrH07ZoApzOUUqxKhtXC5TX3uGlt6u+RUpiVpcE9PrmNQePGgU2/K/e a5JOxs2y8H+oTEoCQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lespinasse.org; i=@lespinasse.org; q=dns/txt; s=srv-14-rsa; t=1619812353; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : from; bh=BLfb3AqVSS1iZWKnBAI32as/v1HrLIIvwM3hMYePNUI=; b=DpIS0cFIofpJRFqMCJ61gjVijTff1dHnb1HPNRT1ZgY0tp/JXtLD9wd4oL+SrkGgcVvBO KMzFQepiwY1MBrqX3MbFVG0nrARR9h8xY42hFlnylvzNSekRPkJlpHirQ5xtxFdzcAU3cB9 1gj9/pjpbfCUZguQONX4fogFhe0N7MEDP1Nk9+74LwpTp5KxOfkBaDq09oPjlQqpEMdGeWr LANhkPfVDjI7lUJ+HQNB5DgVXhPDmlON4GsxCTQDgKHIJg2HVSe2lchFlRpo3M5eUnVe6yG qK6biGFrXSuBT8XVyl8swV17MF/DsmFVvc5054DirfuOL+J7p3G4+H+kBQUw== Received: from zeus.lespinasse.org (zeus.lespinasse.org [10.0.0.150]) by server.lespinasse.org (Postfix) with ESMTPS id 437BF16031E; Fri, 30 Apr 2021 12:52:33 -0700 (PDT) Received: by zeus.lespinasse.org (Postfix, from userid 1000) id 3666A19F521; Fri, 30 Apr 2021 12:52:33 -0700 (PDT) From: Michel Lespinasse To: Linux-MM , Linux-Kernel Cc: Laurent Dufour , Peter Zijlstra , Michal Hocko , Matthew Wilcox , Rik van Riel , Paul McKenney , Andrew Morton , Suren Baghdasaryan , Joel Fernandes , Andy Lutomirski , Michel Lespinasse Subject: [PATCH 09/29] mm: add do_handle_mm_fault() Date: Fri, 30 Apr 2021 12:52:10 -0700 Message-Id: <20210430195232.30491-10-michel@lespinasse.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210430195232.30491-1-michel@lespinasse.org> References: <20210430195232.30491-1-michel@lespinasse.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a new do_handle_mm_fault function, which extends the existing handle_mm_fault() API by adding an mmap sequence count, to be used in the FAULT_FLAG_SPECULATIVE case. In the initial implementation, FAULT_FLAG_SPECULATIVE always fails (by returning VM_FAULT_RETRY). The existing handle_mm_fault() API is kept as a wrapper around do_handle_mm_fault() so that we do not have to immediately update every handle_mm_fault() call site. Signed-off-by: Michel Lespinasse --- include/linux/mm.h | 12 +++++++++--- mm/memory.c | 10 +++++++--- 2 files changed, 16 insertions(+), 6 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 021fdab5b721..d5988e78e6ab 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1724,9 +1724,15 @@ int generic_error_remove_page(struct address_space *mapping, struct page *page); int invalidate_inode_page(struct page *page); #ifdef CONFIG_MMU -extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma, - unsigned long address, unsigned int flags, - struct pt_regs *regs); +extern vm_fault_t do_handle_mm_fault(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + unsigned long seq, struct pt_regs *regs); +static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + struct pt_regs *regs) +{ + return do_handle_mm_fault(vma, address, flags, 0, regs); +} extern int fixup_user_fault(struct mm_struct *mm, unsigned long address, unsigned int fault_flags, bool *unlocked); diff --git a/mm/memory.c b/mm/memory.c index 217c31c616f4..8258ff93a055 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4509,11 +4509,15 @@ static inline void mm_account_fault(struct pt_regs *regs, * The mmap_lock may have been released depending on flags and our * return value. See filemap_fault() and __lock_page_or_retry(). */ -vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address, - unsigned int flags, struct pt_regs *regs) +vm_fault_t do_handle_mm_fault(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + unsigned long seq, struct pt_regs *regs) { vm_fault_t ret; + if (flags & FAULT_FLAG_SPECULATIVE) + return VM_FAULT_RETRY; + __set_current_state(TASK_RUNNING); count_vm_event(PGFAULT); @@ -4555,7 +4559,7 @@ vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address, return ret; } -EXPORT_SYMBOL_GPL(handle_mm_fault); +EXPORT_SYMBOL_GPL(do_handle_mm_fault); #ifndef __PAGETABLE_P4D_FOLDED /* -- 2.20.1