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=-9.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 AE27BC433DF for ; Fri, 19 Jun 2020 16:07:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 73FD421532 for ; Fri, 19 Jun 2020 16:07:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="NwiIi3Fr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 73FD421532 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 21A4C8D00B6; Fri, 19 Jun 2020 12:07:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1C9DF8D00AD; Fri, 19 Jun 2020 12:07:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0E10E8D00B6; Fri, 19 Jun 2020 12:07:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0117.hostedemail.com [216.40.44.117]) by kanga.kvack.org (Postfix) with ESMTP id E4EAA8D00AD for ; Fri, 19 Jun 2020 12:07:29 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 991CB181AC9C6 for ; Fri, 19 Jun 2020 16:07:29 +0000 (UTC) X-FDA: 76946441418.28.aunt22_5812bfa26e1a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id E3A4E110F2D for ; Fri, 19 Jun 2020 16:05:50 +0000 (UTC) X-HE-Tag: aunt22_5812bfa26e1a X-Filterd-Recvd-Size: 6673 Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by imf34.hostedemail.com (Postfix) with ESMTP for ; Fri, 19 Jun 2020 16:05:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592582749; h=from:from: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=oYNDwtlfjBw7SDjKSzeBn7nLzHhEdZ/Papn4VLBZIoQ=; b=NwiIi3FrTXGtSGd/onF0Gsi5EHoR9M5HBXIgqFIo2P301JrqmL/l71z3LK/FM0SvaOGkP1 axud4pPuD9umQV+EUZvqQ7gnnCS5gS+6jLO+JWphHrvVb5d9v+GtS/1A4oTt4auo0hpy56 1CrqUDz60y31Fg9v4hq+F4AnkYGrjgw= Received: from mail-qk1-f197.google.com (mail-qk1-f197.google.com [209.85.222.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-199-8tt_wdFeOw2on-5hO7py_Q-1; Fri, 19 Jun 2020 12:05:48 -0400 X-MC-Unique: 8tt_wdFeOw2on-5hO7py_Q-1 Received: by mail-qk1-f197.google.com with SMTP id a6so7459684qka.9 for ; Fri, 19 Jun 2020 09:05:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=oYNDwtlfjBw7SDjKSzeBn7nLzHhEdZ/Papn4VLBZIoQ=; b=PC/PLa+MbLwlUyit92tmiLwE31k6SSmaerPNoJZSmqfW02NNi8S1EBRW2dYgHdks+T r+ki/36+juNWqnwNzBGARFFXGyfbLi5ofzik1zS00TddWv/IcrXvJOXlJ8Rrl9dQyN1B mzXadGWOJzDiNvXZ4i53dn7BxTZzfzMw4dThFF0ErxJBmtDvhMzZaXvy2CPdfV4LbIZ/ 45Yw9HCRYYGR1nxR011OKxiV5UR5WWajE0XE89gyok03Zd9SmcnLw1VGHm93vLA0F3W/ dR/2RD+wpwGxHZnpa1dbf8/zkihSl+x/uujBaYYc7XvjWf7iJJusUoOggAKWKfucXkQl AiXQ== X-Gm-Message-State: AOAM532YKdpIXhpokiJppyOiE7Yej/p9OmAcfvuvwmgzQZ5xkHI2dC/5 fd7Z1FERw7RG7Jgm8jhh38XglG9cHV4IQRvJHlnxRVKdQVS+39AcUtV4GfXLrSarwzoA1H4w277 x6Hc5+D/dFng= X-Received: by 2002:aed:21c8:: with SMTP id m8mr4187962qtc.224.1592582747582; Fri, 19 Jun 2020 09:05:47 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxzQfwrOgEHeZ4fmlf+FrgeIhkxqk3pvz1Rd9/fj39BAorh/CRlZ+KkHZPVWnZcxaKSEJpm8Q== X-Received: by 2002:aed:21c8:: with SMTP id m8mr4187936qtc.224.1592582747304; Fri, 19 Jun 2020 09:05:47 -0700 (PDT) Received: from xz-x1.redhat.com ([2607:9880:19c0:32::2]) by smtp.gmail.com with ESMTPSA id g11sm6412604qkk.123.2020.06.19.09.05.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Jun 2020 09:05:46 -0700 (PDT) From: Peter Xu To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Gerald Schaefer , peterx@redhat.com, Andrew Morton , Andrea Arcangeli , Will Deacon , Michael Ellerman , Linus Torvalds , Russell King , linux-arm-kernel@lists.infradead.org Subject: [PATCH 04/26] mm/arm: Use general page fault accounting Date: Fri, 19 Jun 2020 12:05:16 -0400 Message-Id: <20200619160538.8641-5-peterx@redhat.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200619160538.8641-1-peterx@redhat.com> References: <20200619160538.8641-1-peterx@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: E3A4E110F2D X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 Content-Transfer-Encoding: quoted-printable 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: Use the general page fault accounting by passing regs into handle_mm_faul= t(). It naturally solve the issue of multiple page fault accounting when page = fault retry happened. To do this, we need to pass the pt_regs pointer into __do_page_fault(). Fix PERF_COUNT_SW_PAGE_FAULTS perf event manually for page fault retries,= by moving it before taking mmap_sem. CC: Russell King CC: Will Deacon CC: linux-arm-kernel@lists.infradead.org Signed-off-by: Peter Xu --- arch/arm/mm/fault.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 0d6be0f4f27c..8530befee012 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -201,7 +201,8 @@ static inline bool access_error(unsigned int fsr, str= uct vm_area_struct *vma) =20 static vm_fault_t __kprobes __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int f= sr, - unsigned int flags, struct task_struct *tsk) + unsigned int flags, struct task_struct *tsk, + struct pt_regs *regs) { struct vm_area_struct *vma; vm_fault_t fault; @@ -223,7 +224,7 @@ __do_page_fault(struct mm_struct *mm, unsigned long a= ddr, unsigned int fsr, goto out; } =20 - return handle_mm_fault(vma, addr & PAGE_MASK, flags, NULL); + return handle_mm_fault(vma, addr & PAGE_MASK, flags, regs); =20 check_stack: /* Don't allow expansion below FIRST_USER_ADDRESS */ @@ -265,6 +266,8 @@ do_page_fault(unsigned long addr, unsigned int fsr, s= truct pt_regs *regs) if ((fsr & FSR_WRITE) && !(fsr & FSR_CM)) flags |=3D FAULT_FLAG_WRITE; =20 + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); + /* * As per x86, we may deadlock here. However, since the kernel only * validly references user space from well defined areas of the code, @@ -289,7 +292,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, s= truct pt_regs *regs) #endif } =20 - fault =3D __do_page_fault(mm, addr, fsr, flags, tsk); + fault =3D __do_page_fault(mm, addr, fsr, flags, tsk, regs); =20 /* If we need to retry but a fatal signal is pending, handle the * signal first. We do not need to release the mmap_sem because @@ -301,23 +304,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, = struct pt_regs *regs) return 0; } =20 - /* - * Major/minor page fault accounting is only done on the - * initial attempt. If we go through a retry, it is extremely - * likely that the page will be found in page cache at that point. - */ - - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); if (!(fault & VM_FAULT_ERROR) && flags & FAULT_FLAG_ALLOW_RETRY) { - if (fault & VM_FAULT_MAJOR) { - tsk->maj_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, - regs, addr); - } else { - tsk->min_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, - regs, addr); - } if (fault & VM_FAULT_RETRY) { flags |=3D FAULT_FLAG_TRIED; goto retry; --=20 2.26.2