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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 83A6EC47404 for ; Mon, 7 Oct 2019 16:51:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 559842084D for ; Mon, 7 Oct 2019 16:51:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570467106; bh=rbJXiYsft/c1AQX7jWydtI8lRj1XxLZmEODMfBy6xnA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=NS8nDZFQS0Xx3R8Mpx1DXOSBsa/0Wvz8zThzqTt2W4Jaf8BQ+MtrAcXAkuGPkotgK 7L+RHR48dNLE3E018yOkBV1z1Rzg+VIOhjZNM5aCty1TFNy/tKMKsiV+2eBtfPByC4 p8ZJ8NB6VtfOHvkg7Wif2jG3KTzpgae4LAJKEsks= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728672AbfJGQvp (ORCPT ); Mon, 7 Oct 2019 12:51:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:40678 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727935AbfJGQvo (ORCPT ); Mon, 7 Oct 2019 12:51:44 -0400 Received: from localhost (lfbn-ncy-1-150-155.w83-194.abo.wanadoo.fr [83.194.232.155]) (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 DF1462070B; Mon, 7 Oct 2019 16:51:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570467104; bh=rbJXiYsft/c1AQX7jWydtI8lRj1XxLZmEODMfBy6xnA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=FUBbN/a9T3gpW7OEfYIdJNqjKk0perCmfvxVYjLXrlWFQ07Ruicqw6//IgTz4kMXB RBwZ+BsgxpFFTDE1So5Nls79w6FCJzsq4aBdKXKfYFLmlHEAwqZRlrsNB0y1yU+EKi srUXZmf/pXg/hASjzXyUekEOr5270KEftMB57ISc= Date: Mon, 7 Oct 2019 18:51:41 +0200 From: Frederic Weisbecker To: Ingo Molnar Cc: Peter Zijlstra , LKML , Wanpeng Li , Thomas Gleixner , Yauheni Kaliuta , Rik van Riel Subject: Re: [PATCH 0/2] vtime: Remove pair of seqcount on context switch Message-ID: <20191007165140.GA31013@lenoir> References: <20191003161745.28464-1-frederic@kernel.org> <20191007162031.GA7676@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191007162031.GA7676@gmail.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 07, 2019 at 06:20:31PM +0200, Ingo Molnar wrote: > > * Frederic Weisbecker wrote: > > > Extracted from a larger queue that fixes kcpustat on nohz_full, these > > two patches have value on their own as they remove two write barriers > > on nohz_full context switch. > > > > Frederic Weisbecker (2): > > vtime: Rename vtime_account_system() to vtime_account_kernel() > > vtime: Spare a seqcount lock/unlock cycle on context switch > > > > arch/ia64/kernel/time.c | 4 +-- > > arch/powerpc/kernel/time.c | 6 ++-- > > arch/s390/kernel/vtime.c | 4 +-- > > include/linux/context_tracking.h | 4 +-- > > include/linux/vtime.h | 38 ++++++++++++------------ > > kernel/sched/cputime.c | 50 ++++++++++++++++++-------------- > > 6 files changed, 57 insertions(+), 49 deletions(-) > > Which tree is this against? Doesn't apply cleanly to v5.4-rc2 nor v5.3. > Does it have any prereqs perhaps? Indeed, you need to apply this fix first: https://lore.kernel.org/lkml/20190925214242.21873-1-frederic@kernel.org/ "[PATCH] sched/vtime: Fix guest/system mis-accounting on task switch" Thanks!