Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754971AbcKUWHO (ORCPT ); Mon, 21 Nov 2016 17:07:14 -0500 Received: from mail-vk0-f43.google.com ([209.85.213.43]:34549 "EHLO mail-vk0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754282AbcKUWHM (ORCPT ); Mon, 21 Nov 2016 17:07:12 -0500 MIME-Version: 1.0 In-Reply-To: <1479765897-29992-1-git-send-email-joelaf@google.com> References: <1479765897-29992-1-git-send-email-joelaf@google.com> From: Joel Fernandes Date: Mon, 21 Nov 2016 14:06:50 -0800 Message-ID: Subject: Re: [PATCH 0/2] Introduce a fast boot clock and add it as trace clock To: LKML Cc: Joel Fernandes , Steven Rostedt , Thomas Gleixner , John Stultz , Ingo Molnar Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1299 Lines: 34 On Mon, Nov 21, 2016 at 2:04 PM, Joel Fernandes wrote: > Currently no trace clock can account for suspend time, using monotonic during > tracing in the suspend path means the trace times wont be advaced. Using the > boot clock with ktime_get_with_offset is not an option due to live locking > concerns in NMI context as suggested by Thomas [1]. > These patches add a fast boot clock based on fast monotonic clock and adds > a trace clock based on it which solves both these issues. > > Changes since RFC: > - Moved the ktime_t offsets to the end of tk_fast > - use unlikely to optimize for the monotonic case > Please scratch these patches, I didn't make a change I had to since the RFC. Sorry for the noise! > [1] https://lkml.org/lkml/2016/11/20/75 > > Joel Fernandes (2): > timekeeping: Introduce a fast boot clock derived from fast monotonic > clock > trace: Add an option for boot clock as trace clock > > kernel/time/timekeeping.c | 36 ++++++++++++++++++++++++++++++------ > kernel/trace/trace.c | 1 + > 2 files changed, 31 insertions(+), 6 deletions(-) > > Cc: Steven Rostedt > Cc: Thomas Gleixner > Cc: John Stultz > Cc: Ingo Molnar > -- > 2.8.0.rc3.226.g39d4020 >