linux-kernel - Re: [PATCH v5 05/10] acpi/battery: Move handler installing logic to driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <f875638a-ea61-04cc-7621-974d4bd2dd34@intel.com>
Date:   Fri, 30 Jun 2023 11:48:51 +0200
From:   "Wilczynski, Michal" <michal.wilczynski@...el.com>
To:     "Rafael J. Wysocki" <rafael@...nel.org>
CC:     <linux-acpi@...r.kernel.org>, <dan.j.williams@...el.com>,
        <vishal.l.verma@...el.com>, <lenb@...nel.org>,
        <dave.jiang@...el.com>, <ira.weiny@...el.com>,
        <rui.zhang@...el.com>, <linux-kernel@...r.kernel.org>,
        <nvdimm@...ts.linux.dev>,
        "Rafael J . Wysocki" <rafael.j.wysocki@...el.com>
Subject: Re: [PATCH v5 05/10] acpi/battery: Move handler installing logic to
 driver



On 6/29/2023 6:05 PM, Rafael J. Wysocki wrote:
> On Fri, Jun 16, 2023 at 6:51 PM Michal Wilczynski
> <michal.wilczynski@...el.com> wrote:
>> Currently logic for installing notifications from ACPI devices is
>> implemented using notify callback in struct acpi_driver. Preparations
>> are being made to replace acpi_driver with more generic struct
>> platform_driver, which doesn't contain notify callback. Furthermore
>> as of now handlers are being called indirectly through
>> acpi_notify_device(), which decreases performance.
>>
>> Call acpi_dev_install_notify_handler() at the end of .add() callback.
>> Call acpi_dev_remove_notify_handler() at the beginning of .remove()
>> callback. Change arguments passed to the notify function to match with
>> what's required by acpi_install_notify_handler(). Remove .notify
>> callback initialization in acpi_driver.
>>
>> While at it, fix lack of whitespaces in .remove() callback.
>>
>> Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
>> Signed-off-by: Michal Wilczynski <michal.wilczynski@...el.com>
>> ---
>>  drivers/acpi/battery.c | 30 ++++++++++++++++++++++++------
>>  1 file changed, 24 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
>> index 9c67ed02d797..6337e7b1f6e1 100644
>> --- a/drivers/acpi/battery.c
>> +++ b/drivers/acpi/battery.c
>> @@ -1034,11 +1034,14 @@ static void acpi_battery_refresh(struct acpi_battery *battery)
>>  }
>>
>>  /* Driver Interface */
>> -static void acpi_battery_notify(struct acpi_device *device, u32 event)
>> +static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
>>  {
>> -       struct acpi_battery *battery = acpi_driver_data(device);
>> +       struct acpi_device *device = data;
>> +       struct acpi_battery *battery;
>>         struct power_supply *old;
>>
>> +       battery = acpi_driver_data(device);
>> +
>>         if (!battery)
>>                 return;
>>         old = battery->bat;
>> @@ -1212,13 +1215,23 @@ static int acpi_battery_add(struct acpi_device *device)
>>
>>         device_init_wakeup(&device->dev, 1);
>>
>> -       return result;
>> +       result = acpi_dev_install_notify_handler(device,
>> +                                                ACPI_ALL_NOTIFY,
>> +                                                acpi_battery_notify);
>> +       if (result)
>> +               goto fail_deinit_wakup_and_unregister;
> You could call the label "fail_pm", for example, which would be more
> concise and so slightly easier to follow, without any loss of clarity
> AFAICS.

Sure

>
>> +
>> +       return 0;
>>
>> +fail_deinit_wakup_and_unregister:
>> +       device_init_wakeup(&device->dev, 0);
>> +       unregister_pm_notifier(&battery->pm_nb);
>>  fail:
>>         sysfs_remove_battery(battery);
>>         mutex_destroy(&battery->lock);
>>         mutex_destroy(&battery->sysfs_lock);
>>         kfree(battery);
>> +
>>         return result;
>>  }
>>
>> @@ -1228,10 +1241,17 @@ static void acpi_battery_remove(struct acpi_device *device)
>>
>>         if (!device || !acpi_driver_data(device))
>>                 return;
>> -       device_init_wakeup(&device->dev, 0);
>> +
>>         battery = acpi_driver_data(device);
>> +
>> +       acpi_dev_remove_notify_handler(device,
>> +                                      ACPI_ALL_NOTIFY,
>> +                                      acpi_battery_notify);
>> +
>> +       device_init_wakeup(&device->dev, 0);
>>         unregister_pm_notifier(&battery->pm_nb);
>>         sysfs_remove_battery(battery);
>> +
>>         mutex_destroy(&battery->lock);
>>         mutex_destroy(&battery->sysfs_lock);
>>         kfree(battery);
>> @@ -1264,11 +1284,9 @@ static struct acpi_driver acpi_battery_driver = {
>>         .name = "battery",
>>         .class = ACPI_BATTERY_CLASS,
>>         .ids = battery_device_ids,
>> -       .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
>>         .ops = {
>>                 .add = acpi_battery_add,
>>                 .remove = acpi_battery_remove,
>> -               .notify = acpi_battery_notify,
>>                 },
>>         .drv.pm = &acpi_battery_pm,
>>  };
>> --
>> 2.41.0
>>