From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from g5t0008.atlanta.hp.com (g5t0008.atlanta.hp.com [15.192.0.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "smtp.hp.com", Issuer "VeriSign Class 3 Secure Server CA - G3" (not verified)) by ozlabs.org (Postfix) with ESMTPS id E1CAA2C0331 for ; Fri, 11 Jan 2013 11:01:16 +1100 (EST) From: Toshi Kani To: rjw@sisk.pl, lenb@kernel.org, gregkh@linuxfoundation.org, akpm@linux-foundation.org Subject: [RFC PATCH v2 04/12] cpu: Add cpu hotplug handlers Date: Thu, 10 Jan 2013 16:40:22 -0700 Message-Id: <1357861230-29549-5-git-send-email-toshi.kani@hp.com> In-Reply-To: <1357861230-29549-1-git-send-email-toshi.kani@hp.com> References: <1357861230-29549-1-git-send-email-toshi.kani@hp.com> Cc: linux-s390@vger.kernel.org, Toshi Kani , jiang.liu@huawei.com, wency@cn.fujitsu.com, linux-mm@kvack.org, yinghai@kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, isimatu.yasuaki@jp.fujitsu.com, srivatsa.bhat@linux.vnet.ibm.com, guohanjun@huawei.com, bhelgaas@google.com, linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Added cpu hotplug handlers. cpu_add_execute() onlines requested cpus for hot-add & online operations, and cpu_del_execute() offlines them for hot-delete & offline operations. They are also used for rollback as well. cpu_del_validate() fails a request if cpu0 is requested to delete. Signed-off-by: Toshi Kani --- drivers/base/cpu.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 6345294..05534ad 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include "base.h" @@ -324,10 +326,115 @@ static void __init cpu_dev_register_generic(void) #endif } +#ifdef CONFIG_HOTPLUG_CPU +static int cpu_del_execute(struct shp_request *req, int rollback); + +static int cpu_add_execute(struct shp_request *req, int rollback) +{ + struct shp_device *shp_dev; + u32 cpu; + int ret; + + if (rollback) + return cpu_del_execute(req, 0); + + list_for_each_entry(shp_dev, &req->dev_list, list) { + if (shp_dev->class != SHP_CLS_CPU) + continue; + + cpu = shp_dev->info.cpu.cpu_id; + + if (cpu_online(cpu)) + continue; + + ret = cpu_up(cpu); + if (!ret) { + /* REVISIT: need a way to set a cpu dev for hot-plug */ + if (shp_is_online_op(req->operation)) + kobject_uevent(&shp_dev->device->kobj, + KOBJ_ONLINE); + } else { + pr_err("cpu: Failed to online cpu %d\n", cpu); + /* fall-thru */ + } + } + + return 0; +} + +static int cpu_del_validate(struct shp_request *req, int rollback) +{ + struct shp_device *shp_dev; + + if (rollback) + return 0; + + list_for_each_entry(shp_dev, &req->dev_list, list) { + if (shp_dev->class != SHP_CLS_CPU) + continue; + + /* + * cpu 0 cannot be offlined. This check can be removed when + * cpu 0 offline is supported. + */ + if (shp_dev->info.cpu.cpu_id == 0) + return -EINVAL; + } + + return 0; +} + +static int cpu_del_execute(struct shp_request *req, int rollback) +{ + struct shp_device *shp_dev; + u32 cpu; + int ret; + + if (rollback) + return cpu_add_execute(req, 0); + + list_for_each_entry(shp_dev, &req->dev_list, list) { + if (shp_dev->class != SHP_CLS_CPU) + continue; + + cpu = shp_dev->info.cpu.cpu_id; + + if (!cpu_online(cpu)) + continue; + + ret = cpu_down(cpu); + if (!ret) { + /* REVISIT: need a way to set a cpu dev for hot-plug */ + if (shp_is_online_op(req->operation)) + kobject_uevent(&shp_dev->device->kobj, + KOBJ_OFFLINE); + } else { + pr_err("cpu: Failed to offline cpu %d\n", cpu); + return ret; + } + } + + return 0; +} + +static void __init cpu_shp_init(void) +{ + shp_register_handler(SHP_ADD_EXECUTE, cpu_add_execute, + SHP_CPU_ADD_EXECUTE_ORDER); + shp_register_handler(SHP_DEL_VALIDATE, cpu_del_validate, + SHP_CPU_DEL_VALIDATE_ORDER); + shp_register_handler(SHP_DEL_EXECUTE, cpu_del_execute, + SHP_CPU_DEL_EXECUTE_ORDER); +} +#endif /* CONFIG_HOTPLUG_CPU */ + void __init cpu_dev_init(void) { if (subsys_system_register(&cpu_subsys, cpu_root_attr_groups)) panic("Failed to register CPU subsystem"); cpu_dev_register_generic(); +#ifdef CONFIG_HOTPLUG_CPU + cpu_shp_init(); +#endif }