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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 949E8C43381 for ; Thu, 28 Feb 2019 19:10:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6FED120C01 for ; Thu, 28 Feb 2019 19:10:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731523AbfB1TKU (ORCPT ); Thu, 28 Feb 2019 14:10:20 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33994 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726214AbfB1TKT (ORCPT ); Thu, 28 Feb 2019 14:10:19 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3751E30BDECB; Thu, 28 Feb 2019 19:10:19 +0000 (UTC) Received: from llong.com (ovpn-121-201.rdu2.redhat.com [10.10.121.201]) by smtp.corp.redhat.com (Postfix) with ESMTP id 869AB60BE0; Thu, 28 Feb 2019 19:10:14 +0000 (UTC) From: Waiman Long To: Peter Zijlstra , Ingo Molnar , Will Deacon , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Arnd Bergmann , Borislav Petkov , "H. Peter Anvin" , Davidlohr Bueso , Linus Torvalds , Andrew Morton , Tim Chen , Waiman Long Subject: [PATCH-tip v3 00/11] locking/rwsem: Rwsem rearchitecture part 1 Date: Thu, 28 Feb 2019 14:09:30 -0500 Message-Id: <1551380981-3113-1-git-send-email-longman@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Thu, 28 Feb 2019 19:10:19 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org v3: - Add patch 11 to move count and owner together as suggested by Linus. - Reword the commit log of patch 2 to clarify the intent of that patch. v2: - Sync up to v4 of the part 0 patch. - Remove the rwsem.h->rwsem-xadd.h renaming patch & change patches to modify rwsem.h instead of rwsem-xadd.h. - Add a new patch to micro-optimize rwsem_try_read_lock_unqueued(). This is part 1 of a 3-part (0/1/2) series to rearchitect the internal operation of rwsem. This depends on the v4 part 0 patches sent out previously https://lore.kernel.org/lkml/1550095217-12047-1-git-send-email-longman@redhat.com This part lays the foundation for part 2 without making any functional changes. This part includes the following changes: 1) Move code around and micro-optimize rwsem_try_read_lock_unqueued() (patches 1-4). 2) Enhance the DEBUG_RWSEMS_WARN_ON() macro to provide more information and add additional checks (patches 5 & 6). 3) Make the core qspinlock_stat.h code generic (lock event counting) so that it can be used by all the architectures as well as other locking subsystems such as rwsem (patches 7-10). Lock event counting help us visualize how frequently a code path is being used as well as spotting abnormal behavior due to bugs in the code without noticeably affecting kernel performance and hence behavior. Both (2) and (3) are useful debugging aids. Waiman Long (11): locking/rwsem: Relocate rwsem_down_read_failed() locking/rwsem: Move owner setting code from rwsem.c to rwsem.h locking/rwsem: Move rwsem internal function declarations to rwsem-xadd.h locking/rwsem: Micro-optimize rwsem_try_read_lock_unqueued() locking/rwsem: Add debug check for __down_read*() locking/rwsem: Enhance DEBUG_RWSEMS_WARN_ON() macro locking/qspinlock_stat: Introduce a generic lockevent counting APIs locking/lock_events: Make lock_events available for all archs & other locks locking/lock_events: Don't show pvqspinlock events on bare metal locking/rwsem: Enable lock event counting locking/rwsem: Optimize rwsem structure for uncontended lock acquisition arch/Kconfig | 9 ++ arch/x86/Kconfig | 8 -- include/linux/rwsem.h | 28 +++-- kernel/locking/Makefile | 1 + kernel/locking/lock_events.c | 179 ++++++++++++++++++++++++++ kernel/locking/lock_events.h | 59 +++++++++ kernel/locking/lock_events_list.h | 67 ++++++++++ kernel/locking/qspinlock.c | 8 +- kernel/locking/qspinlock_paravirt.h | 19 +-- kernel/locking/qspinlock_stat.h | 242 +++++++----------------------------- kernel/locking/rwsem-xadd.c | 204 +++++++++++++++--------------- kernel/locking/rwsem.c | 25 +--- kernel/locking/rwsem.h | 47 ++++++- 13 files changed, 538 insertions(+), 358 deletions(-) create mode 100644 kernel/locking/lock_events.c create mode 100644 kernel/locking/lock_events.h create mode 100644 kernel/locking/lock_events_list.h -- 1.8.3.1