From patchwork Mon Sep 30 12:08:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenzhong Duan X-Patchwork-Id: 11168619 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5162D1599 for ; Tue, 1 Oct 2019 12:06:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 300BD21A4C for ; Tue, 1 Oct 2019 12:06:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="T2zDujtl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387643AbfJAMGQ (ORCPT ); Tue, 1 Oct 2019 08:06:16 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:41434 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726219AbfJAMGQ (ORCPT ); Tue, 1 Oct 2019 08:06:16 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C4U42173251; Tue, 1 Oct 2019 12:04:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2019-08-05; bh=ZJU7loQMKeSoP/RlUzFVBDI3b7KBQRKdPz3cE8BrKSw=; b=T2zDujtlnzNEZAYBTPrGPAsOXWfBF6J7caNaZ02j+TqHsWBEoYzS5/wAyc3zLwG2v7mk N19xuaEd3V13gCBlu/Wmi9JrpdhRzFMGt+/EqS1Tdzk+j0aVzmcbERWHG6+YVc335j33 LgR9iLITnZtpx29J88n3ws3ekSo+rsosSRmIMrRlIoSl77gPgr6aoB8SzSWVWcSlKoHg Nf2y6UAbxYZ+E/rWmigk+D8dSZifiOn/6nk0+wO2yL0QCMqEW6et8F9EYHtG04c9d6wO T7hF6gR5mt9nJb2yfxqYs8wDFuh+sLoczaCE5CZZfICNNPBjspTTvuoU5g2pb8an92Di sA== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2v9xxunbsc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:33 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C465w188345; Tue, 1 Oct 2019 12:04:32 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2vbqd0rcfx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:32 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x91C4GJF017650; Tue, 1 Oct 2019 12:04:16 GMT Received: from z2.cn.oracle.com (/10.182.71.205) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 01 Oct 2019 05:04:16 -0700 From: Zhenzhong Duan To: linux-kernel@vger.kernel.org Cc: vkuznets@redhat.com, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, Zhenzhong Duan , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Paolo Bonzini , Radim Krcmar , Sean Christopherson , Wanpeng Li , Jim Mattson , Joerg Roedel , Peter Zijlstra , Will Deacon Subject: [PATCH v2 1/4] x86/kvm: Add "nopvspin" parameter to disable PV spinlocks Date: Mon, 30 Sep 2019 20:08:57 +0800 Message-Id: <1569845340-11884-2-git-send-email-zhenzhong.duan@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> References: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org There are cases where a guest tries to switch spinlocks to bare metal behavior (e.g. by setting "xen_nopvspin" on XEN platform and "hv_nopvspin" on HYPER_V). That feature is missed on KVM, add a new parameter "nopvspin" to disable PV spinlocks for KVM guest. This new parameter is also used to replace "xen_nopvspin" and "hv_nopvspin". The global variable pvspin isn't defined as __initdata as it's used at runtime by XEN guest. Signed-off-by: Zhenzhong Duan Cc: Jonathan Corbet Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Paolo Bonzini Cc: Radim Krcmar Cc: Sean Christopherson Cc: Vitaly Kuznetsov Cc: Wanpeng Li Cc: Jim Mattson Cc: Joerg Roedel Cc: Peter Zijlstra Cc: Will Deacon --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ arch/x86/include/asm/qspinlock.h | 1 + arch/x86/kernel/kvm.c | 7 +++++++ kernel/locking/qspinlock.c | 7 +++++++ 4 files changed, 19 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index c7ac2f3..4b956d8 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5330,6 +5330,10 @@ as generic guest with no PV drivers. Currently support XEN HVM, KVM, HYPER_V and VMWARE guest. + nopvspin [X86,KVM] Disables the qspinlock slow path + using PV optimizations which allow the hypervisor to + 'idle' the guest on lock contention. + xirc2ps_cs= [NET,PCMCIA] Format: ,,,,,[,[,[,]]] diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h index 444d6fd..34a4484 100644 --- a/arch/x86/include/asm/qspinlock.h +++ b/arch/x86/include/asm/qspinlock.h @@ -32,6 +32,7 @@ static __always_inline u32 queued_fetch_set_pending_acquire(struct qspinlock *lo extern void __pv_init_lock_hash(void); extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); extern void __raw_callee_save___pv_queued_spin_unlock(struct qspinlock *lock); +extern bool pvspin; #define queued_spin_unlock queued_spin_unlock /** diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index e820568..a4f108d 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -842,6 +842,13 @@ void __init kvm_spinlock_init(void) if (num_possible_cpus() == 1) return; + if (!pvspin) { + pr_info("PV spinlocks disabled\n"); + static_branch_disable(&virt_spin_lock_key); + return; + } + pr_info("PV spinlocks enabled\n"); + __pv_init_lock_hash(); pv_ops.lock.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath; pv_ops.lock.queued_spin_unlock = diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c index 2473f10..945b510 100644 --- a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -580,4 +580,11 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) #include "qspinlock_paravirt.h" #include "qspinlock.c" +bool pvspin = true; +static __init int parse_nopvspin(char *arg) +{ + pvspin = false; + return 0; +} +early_param("nopvspin", parse_nopvspin); #endif From patchwork Mon Sep 30 12:08:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenzhong Duan X-Patchwork-Id: 11168617 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F375B13BD for ; Tue, 1 Oct 2019 12:06:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C856021924 for ; Tue, 1 Oct 2019 12:06:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="sbVdUiPm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733246AbfJAMGA (ORCPT ); Tue, 1 Oct 2019 08:06:00 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:41068 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726219AbfJAMGA (ORCPT ); Tue, 1 Oct 2019 08:06:00 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C4Rdi173097; Tue, 1 Oct 2019 12:04:28 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2019-08-05; bh=EEFx1lHigtewl5NRAn81FB4CA+LzMW4aRG66eOeJJNU=; b=sbVdUiPmaKEmcJzQySGd+tdSrCCfykUa+LhF24WBGrA3AXT1lM6TrCxJZAxJOMme84jn OQAzSE25TIm0poszHCaivrZkPI0vHDcA5554WGVbNW11Ww5IaIUUvacFrecd1mk/B4ga 5AmSsqTgALF6nrEJ8FyydFNwwd1ojzzWizPqpZmmgeJ3zLGHbXQElbRKHmVJVHeBc8lA hzftjy4fLbXgCBLjUUO+2kUD+ImCydWJedt95qmpPYRRpWFwAZSTyvBKtEuVtseoT+KG 67fgTzI9Bu62G1HEud2rQM4QIONaxrmyDcGs2jGbJfe88ocl7lHhTgH0wReyt6tQzXEX Ww== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2v9xxunbqu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:28 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C49Fi188581; Tue, 1 Oct 2019 12:04:27 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2vbqd0rchd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:27 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x91C4KB9017689; Tue, 1 Oct 2019 12:04:20 GMT Received: from z2.cn.oracle.com (/10.182.71.205) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 01 Oct 2019 05:04:20 -0700 From: Zhenzhong Duan To: linux-kernel@vger.kernel.org Cc: vkuznets@redhat.com, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, Zhenzhong Duan , Paolo Bonzini , Radim Krcmar , Sean Christopherson , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" Subject: [PATCH v2 2/4] x86/kvm: Change print code to use pr_*() format Date: Mon, 30 Sep 2019 20:08:58 +0800 Message-Id: <1569845340-11884-3-git-send-email-zhenzhong.duan@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> References: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org pr_*() is preferred than printk(KERN_* ...), after change all the print in arch/x86/kernel/kvm.c will have "KVM: xxx" style. No functional change. Signed-off-by: Zhenzhong Duan Cc: Paolo Bonzini Cc: Radim Krcmar Cc: Sean Christopherson Cc: Vitaly Kuznetsov Cc: Wanpeng Li Cc: Jim Mattson Cc: Joerg Roedel Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" --- arch/x86/kernel/kvm.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index a4f108d..7b8cf0d 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -7,6 +7,8 @@ * Authors: Anthony Liguori */ +#define pr_fmt(fmt) "KVM: " fmt + #include #include #include @@ -286,7 +288,7 @@ static void kvm_register_steal_time(void) return; wrmsrl(MSR_KVM_STEAL_TIME, (slow_virt_to_phys(st) | KVM_MSR_ENABLED)); - pr_info("kvm-stealtime: cpu %d, msr %llx\n", + pr_info("stealtime: cpu %d, msr %llx\n", cpu, (unsigned long long) slow_virt_to_phys(st)); } @@ -321,7 +323,7 @@ static void kvm_guest_cpu_init(void) wrmsrl(MSR_KVM_ASYNC_PF_EN, pa); __this_cpu_write(apf_reason.enabled, 1); - printk(KERN_INFO"KVM setup async PF for cpu %d\n", + pr_info("setup async PF for cpu %d\n", smp_processor_id()); } @@ -347,7 +349,7 @@ static void kvm_pv_disable_apf(void) wrmsrl(MSR_KVM_ASYNC_PF_EN, 0); __this_cpu_write(apf_reason.enabled, 0); - printk(KERN_INFO"Unregister pv shared memory for cpu %d\n", + pr_info("Unregister pv shared memory for cpu %d\n", smp_processor_id()); } @@ -509,7 +511,7 @@ static void kvm_setup_pv_ipi(void) { apic->send_IPI_mask = kvm_send_ipi_mask; apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself; - pr_info("KVM setup pv IPIs\n"); + pr_info("setup pv IPIs\n"); } static void kvm_smp_send_call_func_ipi(const struct cpumask *mask) @@ -639,11 +641,11 @@ static void __init kvm_guest_init(void) !kvm_para_has_hint(KVM_HINTS_REALTIME) && kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) { smp_ops.send_call_func_ipi = kvm_smp_send_call_func_ipi; - pr_info("KVM setup pv sched yield\n"); + pr_info("setup pv sched yield\n"); } if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/kvm:online", kvm_cpu_online, kvm_cpu_down_prepare) < 0) - pr_err("kvm_guest: Failed to install cpu hotplug callbacks\n"); + pr_err("failed to install cpu hotplug callbacks\n"); #else sev_map_percpu_data(); kvm_guest_cpu_init(); @@ -746,7 +748,7 @@ static __init int kvm_setup_pv_tlb_flush(void) zalloc_cpumask_var_node(per_cpu_ptr(&__pv_tlb_mask, cpu), GFP_KERNEL, cpu_to_node(cpu)); } - pr_info("KVM setup pv remote TLB flush\n"); + pr_info("setup pv remote TLB flush\n"); } return 0; @@ -879,8 +881,8 @@ static void kvm_enable_host_haltpoll(void *i) void arch_haltpoll_enable(unsigned int cpu) { if (!kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) { - pr_err_once("kvm: host does not support poll control\n"); - pr_err_once("kvm: host upgrade recommended\n"); + pr_err_once("host does not support poll control\n"); + pr_err_once("host upgrade recommended\n"); return; } From patchwork Mon Sep 30 12:08:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenzhong Duan X-Patchwork-Id: 11168615 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A420813BD for ; 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Tue, 1 Oct 2019 12:04:24 GMT Received: from z2.cn.oracle.com (/10.182.71.205) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 01 Oct 2019 05:04:23 -0700 From: Zhenzhong Duan To: linux-kernel@vger.kernel.org Cc: vkuznets@redhat.com, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, Zhenzhong Duan , Jonathan Corbet , Boris Ostrovsky , Juergen Gross , Stefano Stabellini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" Subject: [PATCH v2 3/4] xen: Mark "xen_nopvspin" parameter obsolete and map it to "nopvspin" Date: Mon, 30 Sep 2019 20:08:59 +0800 Message-Id: <1569845340-11884-4-git-send-email-zhenzhong.duan@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> References: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Fix stale description of "xen_nopvspin" as we use qspinlock now. Signed-off-by: Zhenzhong Duan Reviewed-by: Juergen Gross Cc: Jonathan Corbet Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" --- Documentation/admin-guide/kernel-parameters.txt | 7 ++++--- arch/x86/xen/spinlock.c | 13 +++++++------ 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 4b956d8..1f0a62f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5303,8 +5303,9 @@ never -- do not unplug even if version check succeeds xen_nopvspin [X86,XEN] - Disables the ticketlock slowpath using Xen PV - optimizations. + Disables the qspinlock slowpath using Xen PV optimizations. + This parameter is obsoleted by "nopvspin" parameter, which + has equivalent effect for XEN platform. xen_nopv [X86] Disables the PV optimizations forcing the HVM guest to @@ -5330,7 +5331,7 @@ as generic guest with no PV drivers. Currently support XEN HVM, KVM, HYPER_V and VMWARE guest. - nopvspin [X86,KVM] Disables the qspinlock slow path + nopvspin [X86,XEN,KVM] Disables the qspinlock slow path using PV optimizations which allow the hypervisor to 'idle' the guest on lock contention. diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 6deb490..092a53f 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -18,7 +18,6 @@ static DEFINE_PER_CPU(int, lock_kicker_irq) = -1; static DEFINE_PER_CPU(char *, irq_name); static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest); -static bool xen_pvspin = true; static void xen_qlock_kick(int cpu) { @@ -68,7 +67,7 @@ void xen_init_lock_cpu(int cpu) int irq; char *name; - if (!xen_pvspin) + if (!pvspin) return; WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n", @@ -93,7 +92,7 @@ void xen_init_lock_cpu(int cpu) void xen_uninit_lock_cpu(int cpu) { - if (!xen_pvspin) + if (!pvspin) return; unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL); @@ -117,9 +116,9 @@ void __init xen_init_spinlocks(void) /* Don't need to use pvqspinlock code if there is only 1 vCPU. */ if (num_possible_cpus() == 1) - xen_pvspin = false; + pvspin = false; - if (!xen_pvspin) { + if (!pvspin) { printk(KERN_DEBUG "xen: PV spinlocks disabled\n"); static_branch_disable(&virt_spin_lock_key); return; @@ -137,7 +136,9 @@ void __init xen_init_spinlocks(void) static __init int xen_parse_nopvspin(char *arg) { - xen_pvspin = false; + pr_notice("\"xen_nopvspin\" is deprecated, please use \"nopvspin\" instead\n"); + if (xen_domain()) + pvspin = false; return 0; } early_param("xen_nopvspin", xen_parse_nopvspin); From patchwork Mon Sep 30 12:09:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhenzhong Duan X-Patchwork-Id: 11168613 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7BFB11902 for ; Tue, 1 Oct 2019 12:05:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5091421924 for ; Tue, 1 Oct 2019 12:05:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="VRQJMsQl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387522AbfJAME6 (ORCPT ); Tue, 1 Oct 2019 08:04:58 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:39764 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732057AbfJAME6 (ORCPT ); Tue, 1 Oct 2019 08:04:58 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C48LR172799; Tue, 1 Oct 2019 12:04:30 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2019-08-05; bh=tmIzy72qo+rS2sy4J+XBqwA5jvB3VFv9TPhVygdVa7Y=; b=VRQJMsQlWcHI5cDsMpqi7PVWUkLh7ENNobf1T6yRegfa6GD84cj467aaVWfXAj0j6peJ CHV9NWR9xl2/4WAdR9bpH13oLwS1okn4u+I0c39dTkJaOXhBR+nDGNqCDHMr+d6vSCAN KNI0u3KjqD7S5MVByVumius9whOs2g9HjOAvUuyUsn2u6lRvxIhBfNIqt8QlElck2OCa 4lSSnpeARZVjLNh7Rq9MH3MfXwpxds68teDFmrlf7BlERa5Vohv81HCyhEvZlmkmu0Ba /u9hzQfhgcD9My2kvb+YCVYXUtRGiQWrpYbGSX5k6H6r9mwkxU5S7eqLF8MbLF8o76ss Xg== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2130.oracle.com with ESMTP id 2v9xxunbrf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:29 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x91C3OGK157533; Tue, 1 Oct 2019 12:04:29 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3020.oracle.com with ESMTP id 2vbnqcs9n8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Oct 2019 12:04:29 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x91C4SRe010289; Tue, 1 Oct 2019 12:04:28 GMT Received: from z2.cn.oracle.com (/10.182.71.205) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 01 Oct 2019 05:04:27 -0700 From: Zhenzhong Duan To: linux-kernel@vger.kernel.org Cc: vkuznets@redhat.com, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, Zhenzhong Duan , Jonathan Corbet , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Sasha Levin , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" Subject: [PATCH v2 4/4] x86/hyperv: Mark "hv_nopvspin" parameter obsolete and map it to "nopvspin" Date: Mon, 30 Sep 2019 20:09:00 +0800 Message-Id: <1569845340-11884-5-git-send-email-zhenzhong.duan@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> References: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9396 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010112 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Includes asm/hypervisor.h in order to reference x86_hyper_type. Signed-off-by: Zhenzhong Duan Cc: Jonathan Corbet Cc: "K. Y. Srinivasan" Cc: Haiyang Zhang Cc: Stephen Hemminger Cc: Sasha Levin Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" --- Documentation/admin-guide/kernel-parameters.txt | 6 +++++- arch/x86/hyperv/hv_spinlock.c | 9 +++++---- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1f0a62f..43f922c 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1436,6 +1436,10 @@ hv_nopvspin [X86,HYPER_V] Disables the paravirt spinlock optimizations which allow the hypervisor to 'idle' the guest on lock contention. + This parameter is obsoleted by "nopvspin" + parameter, which has equivalent effect for + HYPER_V platform. + keep_bootcon [KNL] Do not unregister boot console at start. This is only @@ -5331,7 +5335,7 @@ as generic guest with no PV drivers. Currently support XEN HVM, KVM, HYPER_V and VMWARE guest. - nopvspin [X86,XEN,KVM] Disables the qspinlock slow path + nopvspin [X86,XEN,KVM,HYPER_V] Disables the qspinlock slow path using PV optimizations which allow the hypervisor to 'idle' the guest on lock contention. diff --git a/arch/x86/hyperv/hv_spinlock.c b/arch/x86/hyperv/hv_spinlock.c index 07f21a0..e00e319 100644 --- a/arch/x86/hyperv/hv_spinlock.c +++ b/arch/x86/hyperv/hv_spinlock.c @@ -12,12 +12,11 @@ #include +#include #include #include #include -static bool __initdata hv_pvspin = true; - static void hv_qlock_kick(int cpu) { apic->send_IPI(cpu, X86_PLATFORM_IPI_VECTOR); @@ -64,7 +63,7 @@ __visible bool hv_vcpu_is_preempted(int vcpu) void __init hv_init_spinlocks(void) { - if (!hv_pvspin || !apic || + if (!pvspin || !apic || !(ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) || !(ms_hyperv.features & HV_X64_MSR_GUEST_IDLE_AVAILABLE)) { pr_info("PV spinlocks disabled\n"); @@ -82,7 +81,9 @@ void __init hv_init_spinlocks(void) static __init int hv_parse_nopvspin(char *arg) { - hv_pvspin = false; + pr_notice("\"hv_nopvspin\" is deprecated, please use \"nopvspin\" instead\n"); + if (x86_hyper_type == X86_HYPER_MS_HYPERV) + pvspin = false; return 0; } early_param("hv_nopvspin", hv_parse_nopvspin);