From patchwork Wed Aug 28 18:56:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joao Martins X-Patchwork-Id: 11119669 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 626AE1398 for ; Wed, 28 Aug 2019 18:58:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3542E22CF8 for ; Wed, 28 Aug 2019 18:58:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="dXBgCddk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727046AbfH1S63 (ORCPT ); Wed, 28 Aug 2019 14:58:29 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:48026 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726883AbfH1S62 (ORCPT ); Wed, 28 Aug 2019 14:58:28 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7SIsNP5149828; Wed, 28 Aug 2019 18:57:10 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-type : content-transfer-encoding; s=corp-2019-08-05; bh=DHX8EJq2diorjBQuEzBHm3f716yk934EjUN3J/yyUPg=; b=dXBgCddkZg8k1DcUxkjdn2QHj5PC0AAUl8Shme2Czg6WA6JlI0V6DjX/DU7/eY+GXYt3 MndMKu3XtjVYkorOuwMwwuHBL4b1IZp2upEPibEP+nZxNJH2mQ0oWtqjfeRuvAvwBUMw 74PrOROBxNCO7UhZVXceXMAvD1FJTEb2or665ZbdB6Vn1pN0dykOMAxa8X+0wTIcqNpV QeB/Jr+mh79lni7WuMkJk1nVeLZhmgVxy5oMbS/O588EMssnJ/VL4upf+W7t5179e0MK 5kvldr9OoY7TJEwxSW4cJUW5/pd9R8g03d/htQBzK8xAM+CzJhfGcrC2iYc2vJD/e6wu jA== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2120.oracle.com with ESMTP id 2uny3903yh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 28 Aug 2019 18:57:10 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7SIrLqI078794; Wed, 28 Aug 2019 18:57:09 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3030.oracle.com with ESMTP id 2unvtxq6kf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 28 Aug 2019 18:57:09 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x7SIv7gv030518; Wed, 28 Aug 2019 18:57:07 GMT Received: from paddy.uk.oracle.com (/10.175.206.216) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 28 Aug 2019 11:57:06 -0700 From: Joao Martins To: kvm@vger.kernel.org Cc: Joao Martins , Marcelo Tosatti , linux-kernel@vger.kernel.org, Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , "Rafael J. Wysocki" , Daniel Lezcano , linux-pm@vger.kernel.org, Boris Ostrovsky Subject: [PATCH v1] cpuidle-haltpoll: vcpu hotplug support Date: Wed, 28 Aug 2019 19:56:50 +0100 Message-Id: <20190828185650.16923-1-joao.m.martins@oracle.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9363 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=3 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=992 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908280184 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9363 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908280184 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When cpus != maxcpus cpuidle-haltpoll will fail to register all vcpus past the online ones and thus fail to register the idle driver. This is because cpuidle_add_sysfs() will return with -ENODEV as a consequence from get_cpu_device() return no device for a non-existing CPU. Instead switch to cpuidle_register_driver() and manually register each of the present cpus through cpuhp_setup_state() and future ones that get onlined. This mimics similar logic as intel_idle. Fixes: fa86ee90eb11 ("add cpuidle-haltpoll driver") Signed-off-by: Joao Martins Signed-off-by: Boris Ostrovsky --- arch/x86/include/asm/cpuidle_haltpoll.h | 4 +- arch/x86/kernel/kvm.c | 18 +++---- drivers/cpuidle/cpuidle-haltpoll.c | 65 +++++++++++++++++++++++-- include/linux/cpuidle_haltpoll.h | 4 +- 4 files changed, 70 insertions(+), 21 deletions(-) diff --git a/arch/x86/include/asm/cpuidle_haltpoll.h b/arch/x86/include/asm/cpuidle_haltpoll.h index ff8607d81526..c8b39c6716ff 100644 --- a/arch/x86/include/asm/cpuidle_haltpoll.h +++ b/arch/x86/include/asm/cpuidle_haltpoll.h @@ -2,7 +2,7 @@ #ifndef _ARCH_HALTPOLL_H #define _ARCH_HALTPOLL_H -void arch_haltpoll_enable(void); -void arch_haltpoll_disable(void); +void arch_haltpoll_enable(unsigned int cpu); +void arch_haltpoll_disable(unsigned int cpu); #endif diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 8d150e3732d9..a9b6c4e2446d 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -880,32 +880,26 @@ static void kvm_enable_host_haltpoll(void *i) wrmsrl(MSR_KVM_POLL_CONTROL, 1); } -void arch_haltpoll_enable(void) +void arch_haltpoll_enable(unsigned int cpu) { if (!kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) { - printk(KERN_ERR "kvm: host does not support poll control\n"); - printk(KERN_ERR "kvm: host upgrade recommended\n"); + pr_err_once("kvm: host does not support poll control\n"); + pr_err_once("kvm: host upgrade recommended\n"); return; } - preempt_disable(); /* Enable guest halt poll disables host halt poll */ - kvm_disable_host_haltpoll(NULL); - smp_call_function(kvm_disable_host_haltpoll, NULL, 1); - preempt_enable(); + smp_call_function_single(cpu, kvm_disable_host_haltpoll, NULL, 1); } EXPORT_SYMBOL_GPL(arch_haltpoll_enable); -void arch_haltpoll_disable(void) +void arch_haltpoll_disable(unsigned int cpu) { if (!kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) return; - preempt_disable(); /* Enable guest halt poll disables host halt poll */ - kvm_enable_host_haltpoll(NULL); - smp_call_function(kvm_enable_host_haltpoll, NULL, 1); - preempt_enable(); + smp_call_function_single(cpu, kvm_enable_host_haltpoll, NULL, 1); } EXPORT_SYMBOL_GPL(arch_haltpoll_disable); #endif diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c index 9ac093dcbb01..0d1853a7185e 100644 --- a/drivers/cpuidle/cpuidle-haltpoll.c +++ b/drivers/cpuidle/cpuidle-haltpoll.c @@ -11,12 +11,15 @@ */ #include +#include #include #include #include #include #include +static struct cpuidle_device __percpu *haltpoll_cpuidle_devices; + static int default_enter_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { @@ -46,6 +49,48 @@ static struct cpuidle_driver haltpoll_driver = { .state_count = 2, }; +static int haltpoll_cpu_online(unsigned int cpu) +{ + struct cpuidle_device *dev; + + dev = per_cpu_ptr(haltpoll_cpuidle_devices, cpu); + if (!dev->registered) { + dev->cpu = cpu; + if (cpuidle_register_device(dev)) { + pr_notice("cpuidle_register_device %d failed!\n", cpu); + return -EIO; + } + arch_haltpoll_enable(cpu); + } + + return 0; +} + +static void haltpoll_uninit(void) +{ + unsigned int cpu; + + cpus_read_lock(); + + for_each_online_cpu(cpu) { + struct cpuidle_device *dev = + per_cpu_ptr(haltpoll_cpuidle_devices, cpu); + + if (!dev->registered) + continue; + + arch_haltpoll_disable(cpu); + cpuidle_unregister_device(dev); + } + + cpuidle_unregister(&haltpoll_driver); + + free_percpu(haltpoll_cpuidle_devices); + haltpoll_cpuidle_devices = NULL; + + cpus_read_unlock(); +} + static int __init haltpoll_init(void) { int ret; @@ -56,17 +101,27 @@ static int __init haltpoll_init(void) if (!kvm_para_available()) return 0; - ret = cpuidle_register(&haltpoll_driver, NULL); - if (ret == 0) - arch_haltpoll_enable(); + ret = cpuidle_register_driver(drv); + if (ret < 0) + return ret; + + haltpoll_cpuidle_devices = alloc_percpu(struct cpuidle_device); + if (haltpoll_cpuidle_devices == NULL) { + cpuidle_unregister_driver(drv); + return -ENOMEM; + } + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/haltpoll:online", + haltpoll_cpu_online, NULL); + if (ret < 0) + haltpoll_uninit(); return ret; } static void __exit haltpoll_exit(void) { - arch_haltpoll_disable(); - cpuidle_unregister(&haltpoll_driver); + haltpoll_uninit(); } module_init(haltpoll_init); diff --git a/include/linux/cpuidle_haltpoll.h b/include/linux/cpuidle_haltpoll.h index fe5954c2409e..d50c1e0411a2 100644 --- a/include/linux/cpuidle_haltpoll.h +++ b/include/linux/cpuidle_haltpoll.h @@ -5,11 +5,11 @@ #ifdef CONFIG_ARCH_CPUIDLE_HALTPOLL #include #else -static inline void arch_haltpoll_enable(void) +static inline void arch_haltpoll_enable(unsigned int cpu) { } -static inline void arch_haltpoll_disable(void) +static inline void arch_haltpoll_disable(unsigned int cpu) { } #endif