From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030333AbcJTRbP (ORCPT ); Thu, 20 Oct 2016 13:31:15 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:33269 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941069AbcJTRbN (ORCPT ); Thu, 20 Oct 2016 13:31:13 -0400 From: Pan Xinhui To: 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 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, borntraeger@de.ibm.com, rkrcmar@redhat.com, Pan Xinhui Subject: [PATCH v5 0/9] implement vcpu preempted check Date: Thu, 20 Oct 2016 17:27:45 -0400 X-Mailer: git-send-email 2.4.11 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16102017-0048-0000-0000-000001CC4983 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16102017-0049-0000-0000-000046C9DE8F Message-Id: <1476998874-2089-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-10-20_09:,, 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-1610200314 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org change from v4: spilt x86 kvm vcpu preempted check into two patches. add documentation patch. add x86 vcpu preempted check patch under xen add s390 vcpu preempted check patch change from v3: add x86 vcpu preempted check patch 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 in uninx benchmark tests. 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 Christian Borntraeger (1): s390/spinlock: Provide vcpu_is_preempted Juergen Gross (1): x86, xen: support vcpu preempted check Pan Xinhui (7): 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, paravirt: Add interface to support kvm/xen vcpu preempted check x86, kvm: support vcpu preempted check Documentation: virtual: kvm: Support vcpu preempted check Documentation/virtual/kvm/msr.txt | 8 +++++++- arch/powerpc/include/asm/spinlock.h | 8 ++++++++ arch/s390/include/asm/spinlock.h | 8 ++++++++ arch/s390/kernel/smp.c | 9 +++++++-- arch/s390/lib/spinlock.c | 25 ++++++++----------------- arch/x86/include/asm/paravirt_types.h | 2 ++ arch/x86/include/asm/spinlock.h | 8 ++++++++ arch/x86/include/uapi/asm/kvm_para.h | 3 ++- arch/x86/kernel/kvm.c | 12 ++++++++++++ arch/x86/kernel/paravirt-spinlocks.c | 6 ++++++ arch/x86/kvm/x86.c | 18 ++++++++++++++++++ arch/x86/xen/spinlock.c | 3 ++- include/linux/sched.h | 12 ++++++++++++ kernel/locking/mutex.c | 15 +++++++++++++-- kernel/locking/osq_lock.c | 10 +++++++++- kernel/locking/rwsem-xadd.c | 16 +++++++++++++--- 16 files changed, 135 insertions(+), 28 deletions(-) -- 2.4.11