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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5CE46C433DF for ; Wed, 12 Aug 2020 01:38:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2D1AD20658 for ; Wed, 12 Aug 2020 01:38:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597196302; bh=skDb6rIE1dOucJDtpd9y4VvtVMjiWtuTNK63f/moOsw=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=S+GveLpqbuIZ7YKZk63YvBkDhMUFuq0UYZ8C6m7NATVGX9Lc5aAmqnknBfbM5byb2 t6ina56TjlfIM+pIcDE44p0JG5hg3csvWfPibBLr9VNvai9t/+QTOy7Bq7OPhS9tQN nq+jhAq+asaBnG4SMp8O00agg+ldWUPU+KBNo8ic= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726472AbgHLBiU (ORCPT ); Tue, 11 Aug 2020 21:38:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:40622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726235AbgHLBiU (ORCPT ); Tue, 11 Aug 2020 21:38:20 -0400 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 832AF2054F; Wed, 12 Aug 2020 01:38:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597196299; bh=skDb6rIE1dOucJDtpd9y4VvtVMjiWtuTNK63f/moOsw=; h=Date:From:To:Subject:In-Reply-To:From; b=TAwaK9d1w8Mo2ZrKduCfOpg97SgjkzeF6AMF80wb4UFWyJ1e3QKxyy0g+tLzIFE6W Rfb5kR9wMCVjwIRBMQOsgzwAOK/gWF1/gSZ19WhEpNweE6E8OANKvMG/pDDoBTO796 TjCkabdfV9Tnc2Ljw9Ye3QDbgqSKkz2aFQcUHf1M= Date: Tue, 11 Aug 2020 18:38:19 -0700 From: Andrew Morton To: akpm@linux-foundation.org, deanbo422@gmail.com, green.hu@gmail.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, nickhu@andestech.com, peterx@redhat.com, torvalds@linux-foundation.org Subject: [patch 152/165] mm/nds32: use general page fault accounting Message-ID: <20200812013819.iSGvKsBSJ%akpm@linux-foundation.org> In-Reply-To: <20200811182949.e12ae9a472e3b5e27e16ad6c@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Peter Xu Subject: mm/nds32: use general page fault accounting Use the general page fault accounting by passing regs into handle_mm_fault(). It naturally solve the issue of multiple page fault accounting when page fault retry happened. Fix PERF_COUNT_SW_PAGE_FAULTS perf event manually for page fault retries, by moving it before taking mmap_sem. Link: http://lkml.kernel.org/r/20200707225021.200906-13-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: Greentime Hu Cc: Nick Hu Cc: Vincent Chen Signed-off-by: Andrew Morton --- arch/nds32/mm/fault.c | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-) --- a/arch/nds32/mm/fault.c~mm-nds32-use-general-page-fault-accounting +++ a/arch/nds32/mm/fault.c @@ -121,6 +121,8 @@ void do_page_fault(unsigned long entry, if (unlikely(faulthandler_disabled() || !mm)) goto no_context; + 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, @@ -206,7 +208,7 @@ good_area: * the fault. */ - fault = handle_mm_fault(vma, addr, flags, NULL); + fault = handle_mm_fault(vma, addr, flags, regs); /* * If we need to retry but a fatal signal is pending, handle the @@ -228,22 +230,7 @@ good_area: goto bad_area; } - /* - * 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 (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 |= FAULT_FLAG_TRIED; _