From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753118AbeDKSBL (ORCPT ); Wed, 11 Apr 2018 14:01:11 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52032 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752551AbeDKSBG (ORCPT ); Wed, 11 Apr 2018 14:01:06 -0400 From: Will Deacon To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, peterz@infradead.org, mingo@kernel.org, boqun.feng@gmail.com, paulmck@linux.vnet.ibm.com, longman@redhat.com, Will Deacon Subject: [PATCH v2 00/13] kernel/locking: qspinlock improvements Date: Wed, 11 Apr 2018 19:01:07 +0100 Message-Id: <1523469680-17699-1-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, Here's v2 of the qspinlock patches I posted last week: https://lkml.org/lkml/2018/4/5/496 Changes since v1 include: * Use WRITE_ONCE to clear the pending bit if we set it erroneously * Report pending and slowpath acquisitions via the qspinlock stat mechanism [Waiman Long] * Spin for a bounded duration while lock is observed in the pending->locked transition * Use try_cmpxchg to get better codegen on x86 * Reword comments All comments welcome, Will --->8 Jason Low (1): locking/mcs: Use smp_cond_load_acquire() in mcs spin loop Waiman Long (1): locking/qspinlock: Add stat tracking for pending vs slowpath Will Deacon (11): barriers: Introduce smp_cond_load_relaxed and atomic_cond_read_relaxed locking/qspinlock: Bound spinning on pending->locked transition in slowpath locking/qspinlock/x86: Increase _Q_PENDING_LOOPS upper bound locking/qspinlock: Remove unbounded cmpxchg loop from locking slowpath locking/qspinlock: Kill cmpxchg loop when claiming lock from head of queue locking/qspinlock: Use atomic_cond_read_acquire locking/qspinlock: Use smp_cond_load_relaxed to wait for next node locking/qspinlock: Merge struct __qspinlock into struct qspinlock locking/qspinlock: Make queued_spin_unlock use smp_store_release locking/qspinlock: Elide back-to-back RELEASE operations with smp_wmb() locking/qspinlock: Use try_cmpxchg instead of cmpxchg when locking arch/x86/include/asm/qspinlock.h | 21 ++- arch/x86/include/asm/qspinlock_paravirt.h | 3 +- include/asm-generic/atomic-long.h | 2 + include/asm-generic/barrier.h | 27 +++- include/asm-generic/qspinlock.h | 2 +- include/asm-generic/qspinlock_types.h | 32 +++- include/linux/atomic.h | 2 + kernel/locking/mcs_spinlock.h | 10 +- kernel/locking/qspinlock.c | 247 ++++++++++++++---------------- kernel/locking/qspinlock_paravirt.h | 41 ++--- kernel/locking/qspinlock_stat.h | 9 +- 11 files changed, 209 insertions(+), 187 deletions(-) -- 2.1.4