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=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,UNPARSEABLE_RELAY,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 81F0AC43A1D for ; Thu, 12 Jul 2018 00:07:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2BD292146E for ; Thu, 12 Jul 2018 00:07:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="xgEVJfMc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BD292146E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390977AbeGLANN (ORCPT ); Wed, 11 Jul 2018 20:13:13 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:35458 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390955AbeGLANK (ORCPT ); Wed, 11 Jul 2018 20:13:10 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w6C04UP9185776; Thu, 12 Jul 2018 00:04:30 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id; s=corp-2018-07-02; bh=g/Ml0WWStK6JuihHX4vAe1nukI0Qqe6zD+qez1JSnJY=; b=xgEVJfMcU3pPz7uhGZU7ilxzIcScqJ9kACdHRte54d6IYD68NOid2FXYAVBwJPSbZXFF K18RwLdCiZEusl9uJHrDDBD01tUssTFM+Xixj+hUvM1v4tisR3Sff+VDuNttKo5yDUm8 k/+CxMjFORNanPemGLEDhZkobnrxUogdwIZGb2TAa+uMq7F4Q8BVdXQwKa+Mufc2mnnb b/rprF8/1tbEs+l79w0g65Zywa9X+ePjk5+V1ux+TeTrzH46FMO+9ULb10NfTaBq7ztY BYWRA6396qwgDImkeeMRn3cOZLibMljnmDlJYy2mt3bNHeV2sz2piF0hYAGHMY5SPind 5A== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2120.oracle.com with ESMTP id 2k2p7e09g8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 12 Jul 2018 00:04:30 +0000 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w6C04Sfc028772 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 12 Jul 2018 00:04:28 GMT Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w6C04Pcq011210; Thu, 12 Jul 2018 00:04:25 GMT Received: from localhost.localdomain (/73.69.118.222) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 11 Jul 2018 17:04:24 -0700 From: Pavel Tatashin To: steven.sistare@oracle.com, daniel.m.jordan@oracle.com, linux@armlinux.org.uk, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, john.stultz@linaro.org, sboyd@codeaurora.org, x86@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de, hpa@zytor.com, douly.fnst@cn.fujitsu.com, peterz@infradead.org, prarit@redhat.com, feng.tang@intel.com, pmladek@suse.com, gnomes@lxorguk.ukuu.org.uk, linux-s390@vger.kernel.org, pasha.tatashin@oracle.com, boris.ostrovsky@oracle.com, jgross@suse.com Subject: [PATCH v13 00/18] Early boot time stamps Date: Wed, 11 Jul 2018 20:04:01 -0400 Message-Id: <20180712000419.5165-1-pasha.tatashin@oracle.com> X-Mailer: git-send-email 2.18.0 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8951 signatures=668706 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807110252 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org changelog --------- v13 - v12 - Addressed comments from Thomas Gleixner. - Addressed comments from Peter Zijlstra. - Added a patch from Borislav Petkov - Added a new patch: sched: use static key for sched_clock_running - Added xen pv fixes, so clock is initialized when other hypervisors initialize their clocks. Note: I am including kvm/x86: remove kvm memblock dependency, which is part of this series: http://lkml.kernel.org/r/20180706161307.733337643@linutronix.de Because without this patch it is not possible to test this series on KVM. v12 - v11 - split time: replace read_boot_clock64() with read_persistent_wall_and_boot_offset() into four patches - Added two patches one fixes an existing bug with text_poke() another one enables static branches early. Note, because I found and fixed the text_poke() bug, enabling static branching became super easy, as no changes to jump_label* is needed. - Modified x86/tsc: use tsc early to use static branches early, and thus native_sched_clock() is not changed at all. v11 - v10 - Addressed all the comments from Thomas Gleixner. - I added one more patch: "x86/tsc: prepare for early sched_clock" which fixes a problem that I discovered while testing. I am not particularly happy with the fix, as it adds a new argument that is used only in one place, but if you have a suggestion for a different approach on how to address this problem please let me know. v10 - v9 - Added another patch to this series that removes dependency between KVM clock, and memblock allocator. The benefit is that all clocks can now be initialized even earlier. v9 - v8 - Addressed more comments from Dou Liyang v8 - v7 - Addressed comments from Dou Liyang: - Moved tsc_early_init() and tsc_early_fini() to be all inside tsc.c, and changed them to be static. - Removed warning when notsc parameter is used. - Merged with: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git v7 - v6 - Removed tsc_disabled flag, now notsc is equivalent of tsc=unstable - Simplified changes to sched/clock.c, by removing the sched_clock_early() and friends as requested by Peter Zijlstra. We know always use sched_clock() - Modified x86 sched_clock() to return either early boot time or regular. - Added another example why ealry boot time is important v5 - v6 - Added a new patch: time: sync read_boot_clock64() with persistent clock Which fixes missing __init macro, and enabled time discrepancy fix that was noted by Thomas Gleixner - Split "x86/time: read_boot_clock64() implementation" into a separate patch v4 - v5 - Fix compiler warnings on systems with stable clocks. v3 - v4 - Fixed tsc_early_fini() call to be in the 2nd patch as reported by Dou Liyang - Improved comment before __use_sched_clock_early to explain why we need both booleans. - Simplified valid_clock logic in read_boot_clock64(). 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() The early boot time stamps were discussed recently in these threads: http://lkml.kernel.org/r/1527672059-6225-1-git-send-email-feng.tang@intel.com http://lkml.kernel.org/r/1527672059-6225-2-git-send-email-feng.tang@intel.com I updated my series to the latest mainline and sending it again. Peter mentioned he did not like patch 6,7, and we can discuss for a better way to do that, but I think patches 1-5 can be accepted separetly, since they already enable early timestamps on platforms where sched_clock() is available early. Such as KVM. 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://paste.ubuntu.com/26133428/ After: https://paste.ubuntu.com/26133523/ For exaples how early time stamps are used, see this work: Example 1: https://lwn.net/Articles/734374/ - Without early boot time stamps we would not know about the extra time that is spent zeroing struct pages early in boot even when deferred page initialization. Example 2: https://patchwork.kernel.org/patch/10021247/ - If early boot timestamps were available, the engineer who introduced this bug would have noticed the extra time that is spent early in boot. Pavel Tatashin (7): x86/tsc: remove tsc_disabled flag time: sync read_boot_clock64() with persistent clock x86/time: read_boot_clock64() implementation sched: early boot clock kvm/x86: remove kvm memblock dependency x86/paravirt: add active_sched_clock to pv_time_ops x86/tsc: use tsc early Example 3: http://lkml.kernel.org/r/20180615155733.1175-1-pasha.tatashin@oracle.com - Needed early time stamps to show improvement Borislav Petkov (1): x86/CPU: Call detect_nopl() only on the BSP Pavel Tatashin (17): x86: text_poke() may access uninitialized struct pages x86: initialize static branching early x86/tsc: redefine notsc to behave as tsc=unstable kvm/x86: remove kvm memblock dependency x86/xen/time: initialize pv xen time in init_hypervisor_platform x86/xen/time: output xen sched_clock time from 0 s390/time: add read_persistent_wall_and_boot_offset() time: replace read_boot_clock64() with read_persistent_wall_and_boot_offset() time: default boot time offset to local_clock() s390/time: remove read_boot_clock64() ARM/time: remove read_boot_clock64() x86/tsc: calibrate tsc only once x86/tsc: initialize cyc2ns when tsc freq. is determined x86/tsc: use tsc early sched: move sched clock initialization and merge with generic clock sched: early boot clock sched: use static key for sched_clock_running .../admin-guide/kernel-parameters.txt | 2 - Documentation/x86/x86_64/boot-options.txt | 4 +- arch/arm/include/asm/mach/time.h | 3 +- arch/arm/kernel/time.c | 15 +- arch/arm/plat-omap/counter_32k.c | 2 +- arch/s390/kernel/time.c | 15 +- arch/x86/include/asm/kvm_para.h | 2 +- arch/x86/include/asm/text-patching.h | 1 + arch/x86/include/asm/tsc.h | 2 +- arch/x86/kernel/alternative.c | 7 + arch/x86/kernel/cpu/amd.c | 13 +- arch/x86/kernel/cpu/common.c | 40 ++-- arch/x86/kernel/jump_label.c | 11 +- arch/x86/kernel/kvm.c | 1 + arch/x86/kernel/kvmclock.c | 66 +------ arch/x86/kernel/setup.c | 11 +- arch/x86/kernel/tsc.c | 187 +++++++++--------- arch/x86/xen/enlighten_pv.c | 51 +++-- arch/x86/xen/mmu_pv.c | 6 +- arch/x86/xen/suspend_pv.c | 5 +- arch/x86/xen/time.c | 24 +-- arch/x86/xen/xen-ops.h | 6 +- drivers/clocksource/tegra20_timer.c | 2 +- include/linux/sched_clock.h | 5 +- include/linux/timekeeping.h | 3 +- init/main.c | 4 +- kernel/sched/clock.c | 48 +++-- kernel/sched/core.c | 1 - kernel/sched/debug.c | 2 - kernel/time/sched_clock.c | 2 +- kernel/time/timekeeping.c | 62 +++--- 31 files changed, 288 insertions(+), 315 deletions(-) -- 2.18.0