Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753598AbdHKSvn (ORCPT ); Fri, 11 Aug 2017 14:51:43 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:23907 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753158AbdHKSvm (ORCPT ); Fri, 11 Aug 2017 14:51:42 -0400 From: Pavel Tatashin To: x86@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, hpa@zytor.com Subject: [v3 0/2] Early boot time stamps for x86 Date: Fri, 11 Aug 2017 14:50:53 -0400 Message-Id: <1502477455-314781-1-git-send-email-pasha.tatashin@oracle.com> X-Mailer: git-send-email 1.7.1 X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1275 Lines: 44 Resending, fixed the subject. changelog --------- v2 - v3 - Addressed comment from Thomas Gleixner - Timestamps are available a little later in boot but still much earlier than in mainline. This significantly simplified this work. v1 - v2 In patch "x86/tsc: tsc early": - added tsc_adjusted_early() - fixed 32-bit compile error use do_div() Adding early boot time stamps support for x86 machines. SPARC patches for early boot time stamps are already integrated into mainline linux. Sample output ------------- Before: https://hastebin.com/jadaqukubu.scala After: https://hastebin.com/nubipozacu.scala As seen above, currently timestamps are available from around the time when "Security Framework" is initialized. But, 26s already passed until we reached to this point. Pavel Tatashin (2): sched/clock: interface to allow timestamps early in boot x86/tsc: use tsc early arch/x86/include/asm/tsc.h | 4 +++ arch/x86/kernel/setup.c | 10 ++++++-- arch/x86/kernel/time.c | 22 ++++++++++++++++ arch/x86/kernel/tsc.c | 47 ++++++++++++++++++++++++++++++++++ include/linux/sched/clock.h | 4 +++ kernel/sched/clock.c | 61 ++++++++++++++++++++++++++++++++++++++++++++- 6 files changed, 145 insertions(+), 3 deletions(-) -- 2.14.0