Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965319AbcKWP37 (ORCPT ); Wed, 23 Nov 2016 10:29:59 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:44311 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938728AbcKWP34 (ORCPT ); Wed, 23 Nov 2016 10:29:56 -0500 Subject: Re: [PATCH 06/20] hwmon/via-cputemp: Convert to hotplug state machine To: Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org References: <20161117183541.8588-1-bigeasy@linutronix.de> <20161117183541.8588-7-bigeasy@linutronix.de> Cc: rt@linuxtronix.de, Jean Delvare , linux-hwmon@vger.kernel.org From: Guenter Roeck Message-ID: <24e0d47a-ee49-1f0d-ca2a-4158d2480a80@roeck-us.net> Date: Wed, 23 Nov 2016 07:29:45 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20161117183541.8588-7-bigeasy@linutronix.de> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4171 Lines: 144 On 11/17/2016 10:35 AM, Sebastian Andrzej Siewior wrote: > Install the callbacks via the state machine and let the core invoke the > callbacks on the already online CPUs. When the hotplug state is > unregistered the cleanup function is called for each cpu. So both cpu loops > in init() and exit() are not longer required. > > Cc: Jean Delvare > Cc: Guenter Roeck > Cc: linux-hwmon@vger.kernel.org > Signed-off-by: Sebastian Andrzej Siewior I would like to apply this patch, but I can not test it, and I want to make sure it survives multiple removal/insertion sequences. Can someone give me a Tested-by: ? Thanks, Guenter > --- > drivers/hwmon/via-cputemp.c | 61 ++++++++++++--------------------------------- > 1 file changed, 16 insertions(+), 45 deletions(-) > > diff --git a/drivers/hwmon/via-cputemp.c b/drivers/hwmon/via-cputemp.c > index 5b9866b1b437..ee5377ecd7a9 100644 > --- a/drivers/hwmon/via-cputemp.c > +++ b/drivers/hwmon/via-cputemp.c > @@ -220,7 +220,7 @@ struct pdev_entry { > static LIST_HEAD(pdev_list); > static DEFINE_MUTEX(pdev_list_mutex); > > -static int via_cputemp_device_add(unsigned int cpu) > +static int via_cputemp_online(unsigned int cpu) > { > int err; > struct platform_device *pdev; > @@ -261,7 +261,7 @@ static int via_cputemp_device_add(unsigned int cpu) > return err; > } > > -static void via_cputemp_device_remove(unsigned int cpu) > +static int via_cputemp_down_prep(unsigned int cpu) > { > struct pdev_entry *p; > > @@ -272,33 +272,13 @@ static void via_cputemp_device_remove(unsigned int cpu) > list_del(&p->list); > mutex_unlock(&pdev_list_mutex); > kfree(p); > - return; > + return 0; > } > } > mutex_unlock(&pdev_list_mutex); > + return 0; > } > > -static int via_cputemp_cpu_callback(struct notifier_block *nfb, > - unsigned long action, void *hcpu) > -{ > - unsigned int cpu = (unsigned long) hcpu; > - > - switch (action) { > - case CPU_ONLINE: > - case CPU_DOWN_FAILED: > - via_cputemp_device_add(cpu); > - break; > - case CPU_DOWN_PREPARE: > - via_cputemp_device_remove(cpu); > - break; > - } > - return NOTIFY_OK; > -} > - > -static struct notifier_block via_cputemp_cpu_notifier __refdata = { > - .notifier_call = via_cputemp_cpu_callback, > -}; > - > static const struct x86_cpu_id __initconst cputemp_ids[] = { > { X86_VENDOR_CENTAUR, 6, 0xa, }, /* C7 A */ > { X86_VENDOR_CENTAUR, 6, 0xd, }, /* C7 D */ > @@ -307,6 +287,8 @@ static const struct x86_cpu_id __initconst cputemp_ids[] = { > }; > MODULE_DEVICE_TABLE(x86cpu, cputemp_ids); > > +static enum cpuhp_state via_temp_online; > + > static int __init via_cputemp_init(void) > { > int i, err; > @@ -318,44 +300,33 @@ static int __init via_cputemp_init(void) > if (err) > goto exit; > > - cpu_notifier_register_begin(); > - for_each_online_cpu(i) > - via_cputemp_device_add(i); > + err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hwmon/via:online", > + via_cputemp_online, via_cputemp_down_prep); > + if (err < 0) > + goto exit_driver_unreg; > + via_temp_online = err; > > #ifndef CONFIG_HOTPLUG_CPU > if (list_empty(&pdev_list)) { > - cpu_notifier_register_done(); > err = -ENODEV; > - goto exit_driver_unreg; > + goto exit_hp_unreg; > } > #endif > - > - __register_hotcpu_notifier(&via_cputemp_cpu_notifier); > - cpu_notifier_register_done(); > return 0; > > #ifndef CONFIG_HOTPLUG_CPU > +exit_hp_unreg: > + cpuhp_remove_state_nocalls(via_temp_online); > +#endif > exit_driver_unreg: > platform_driver_unregister(&via_cputemp_driver); > -#endif > exit: > return err; > } > > static void __exit via_cputemp_exit(void) > { > - struct pdev_entry *p, *n; > - > - cpu_notifier_register_begin(); > - __unregister_hotcpu_notifier(&via_cputemp_cpu_notifier); > - mutex_lock(&pdev_list_mutex); > - list_for_each_entry_safe(p, n, &pdev_list, list) { > - platform_device_unregister(p->pdev); > - list_del(&p->list); > - kfree(p); > - } > - mutex_unlock(&pdev_list_mutex); > - cpu_notifier_register_done(); > + cpuhp_remove_state(via_temp_online); > platform_driver_unregister(&via_cputemp_driver); > } > >