From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753153AbcF1KoH (ORCPT ); Tue, 28 Jun 2016 06:44:07 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:20350 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752665AbcF1KoC (ORCPT ); Tue, 28 Jun 2016 06:44:02 -0400 X-IBM-Helo: d01dlp03.pok.ibm.com X-IBM-MailFrom: xinhui.pan@linux.vnet.ibm.com From: Pan Xinhui To: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org Cc: peterz@infradead.org, mingo@redhat.com, mpe@ellerman.id.au, paulus@samba.org, benh@kernel.crashing.org, paulmck@linux.vnet.ibm.com, waiman.long@hpe.com, will.deacon@arm.com, boqun.feng@gmail.com, dave@stgolabs.net, schwidefsky@de.ibm.com, Pan Xinhui Subject: [PATCH v2 0/4] implement vcpu preempted check Date: Tue, 28 Jun 2016 10:43:07 -0400 X-Mailer: git-send-email 2.4.11 X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16062810-0056-0000-0000-000000A43762 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16062810-0057-0000-0000-000004BDAF0E Message-Id: <1467124991-13164-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-06-28_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1606280099 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org change fomr v1: a simplier definition of default vcpu_is_preempted skip mahcine type check on ppc, and add config. remove dedicated macro. add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. add more comments thanks boqun and Peter's suggestion. This patch set aims to fix lock holder preemption issues. test-case: perf record -a perf bench sched messaging -g 400 -p && perf report 18.09% sched-messaging [kernel.vmlinux] [k] osq_lock 12.28% sched-messaging [kernel.vmlinux] [k] rwsem_spin_on_owner 5.27% sched-messaging [kernel.vmlinux] [k] mutex_unlock 3.89% sched-messaging [kernel.vmlinux] [k] wait_consider_task 3.64% sched-messaging [kernel.vmlinux] [k] _raw_write_lock_irq 3.41% sched-messaging [kernel.vmlinux] [k] mutex_spin_on_owner.is 2.49% sched-messaging [kernel.vmlinux] [k] system_call We introduce interface bool vcpu_is_preempted(int cpu) and use it in some spin loops of osq_lock, rwsem_spin_on_owner and mutex_spin_on_owner. These spin_on_onwer variant also cause rcu stall before we apply this patch set Pan Xinhui (4): kernel/sched: introduce vcpu preempted check interface powerpc/spinlock: support vcpu preempted check locking/osq: Drop the overload of osq_lock() kernel/locking: Drop the overload of {mutex,rwsem}_spin_on_owner arch/powerpc/include/asm/spinlock.h | 18 ++++++++++++++++++ include/linux/sched.h | 12 ++++++++++++ kernel/locking/mutex.c | 15 +++++++++++++-- kernel/locking/osq_lock.c | 10 +++++++++- kernel/locking/rwsem-xadd.c | 16 +++++++++++++--- 5 files changed, 65 insertions(+), 6 deletions(-) -- 2.4.11