From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3rf2VF1s0yzDqnm for ; Tue, 28 Jun 2016 20:44:04 +1000 (AEST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5SAdF9g024277 for ; Tue, 28 Jun 2016 06:44:02 -0400 Received: from e19.ny.us.ibm.com (e19.ny.us.ibm.com [129.33.205.209]) by mx0b-001b2d01.pphosted.com with ESMTP id 23sp5125tr-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 28 Jun 2016 06:44:01 -0400 Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 28 Jun 2016 06:44:01 -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 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 Message-Id: <1467124991-13164-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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