Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752147AbcJSGrX (ORCPT ); Wed, 19 Oct 2016 02:47:23 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:60262 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751762AbcJSGrV (ORCPT ); Wed, 19 Oct 2016 02:47:21 -0400 Subject: Re: [PATCH v4 0/5] implement vcpu preempted check To: Pan Xinhui , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, xen-devel-request@lists.xenproject.org, kvm@vger.kernel.org References: <1476872416-42752-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, mingo@redhat.com, peterz@infradead.org, paulmck@linux.vnet.ibm.com, will.deacon@arm.com, kernellwp@gmail.com, jgross@suse.com, pbonzini@redhat.com, bsingharora@gmail.com, boqun.feng@gmail.com From: Christian Borntraeger Date: Wed, 19 Oct 2016 08:47:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1476872416-42752-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16101906-0036-0000-0000-000002471042 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16101906-0037-0000-0000-000012E9540B Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-10-19_02:,, 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=8.0.1-1609300000 definitions=main-1610190120 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4393 Lines: 95 On 10/19/2016 12:20 PM, Pan Xinhui wrote: > change from v3: > add x86 vcpu preempted check patch If you want you could add the s390 patch that I provided for your last version. I also gave my Acked-by for all previous patches. > change from v2: > no code change, fix typos, update some comments > change from 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 > > We also have observed some performace improvements. > > PPC test result: > > 1 copy - 0.94% > 2 copy - 7.17% > 4 copy - 11.9% > 8 copy - 3.04% > 16 copy - 15.11% > > details below: > Without patch: > > 1 copy - File Write 4096 bufsize 8000 maxblocks 2188223.0 KBps (30.0 s, 1 samples) > 2 copy - File Write 4096 bufsize 8000 maxblocks 1804433.0 KBps (30.0 s, 1 samples) > 4 copy - File Write 4096 bufsize 8000 maxblocks 1237257.0 KBps (30.0 s, 1 samples) > 8 copy - File Write 4096 bufsize 8000 maxblocks 1032658.0 KBps (30.0 s, 1 samples) > 16 copy - File Write 4096 bufsize 8000 maxblocks 768000.0 KBps (30.1 s, 1 samples) > > With patch: > > 1 copy - File Write 4096 bufsize 8000 maxblocks 2209189.0 KBps (30.0 s, 1 samples) > 2 copy - File Write 4096 bufsize 8000 maxblocks 1943816.0 KBps (30.0 s, 1 samples) > 4 copy - File Write 4096 bufsize 8000 maxblocks 1405591.0 KBps (30.0 s, 1 samples) > 8 copy - File Write 4096 bufsize 8000 maxblocks 1065080.0 KBps (30.0 s, 1 samples) > 16 copy - File Write 4096 bufsize 8000 maxblocks 904762.0 KBps (30.0 s, 1 samples) > > X86 test result: > test-case after-patch before-patch > Execl Throughput | 18307.9 lps | 11701.6 lps > File Copy 1024 bufsize 2000 maxblocks | 1352407.3 KBps | 790418.9 KBps > File Copy 256 bufsize 500 maxblocks | 367555.6 KBps | 222867.7 KBps > File Copy 4096 bufsize 8000 maxblocks | 3675649.7 KBps | 1780614.4 KBps > Pipe Throughput | 11872208.7 lps | 11855628.9 lps > Pipe-based Context Switching | 1495126.5 lps | 1490533.9 lps > Process Creation | 29881.2 lps | 28572.8 lps > Shell Scripts (1 concurrent) | 23224.3 lpm | 22607.4 lpm > Shell Scripts (8 concurrent) | 3531.4 lpm | 3211.9 lpm > System Call Overhead | 10385653.0 lps | 10419979.0 lps > > Pan Xinhui (5): > kernel/sched: introduce vcpu preempted check interface > locking/osq: Drop the overload of osq_lock() > kernel/locking: Drop the overload of {mutex,rwsem}_spin_on_owner > powerpc/spinlock: support vcpu preempted check > x86, kvm: support vcpu preempted check > > arch/powerpc/include/asm/spinlock.h | 8 ++++++++ > arch/x86/include/asm/paravirt_types.h | 6 ++++++ > arch/x86/include/asm/spinlock.h | 8 ++++++++ > arch/x86/include/uapi/asm/kvm_para.h | 3 ++- > arch/x86/kernel/kvm.c | 11 +++++++++++ > arch/x86/kernel/paravirt.c | 11 +++++++++++ > arch/x86/kvm/x86.c | 12 ++++++++++++ > include/linux/sched.h | 12 ++++++++++++ > kernel/locking/mutex.c | 15 +++++++++++++-- > kernel/locking/osq_lock.c | 10 +++++++++- > kernel/locking/rwsem-xadd.c | 16 +++++++++++++--- > 11 files changed, 105 insertions(+), 7 deletions(-) >