On Sun, Sep 27, 2015 at 06:48:44AM +0100, Chen Yu wrote:
> From: Zhang Rui <[email protected]>
>
> When a new cooling device is registered, we need to update the
> thermal zone to set the new registered cooling device to a proper
> state.
>
> This fixes a problem that the system is cool, while the fan devices
> are left running on full speed after boot, if fan device is registered
> after thermal zone device.
>
> CC: <[email protected]> #3.18+
> Reference:https://bugzilla.kernel.org/show_bug.cgi?id=92431
> Tested-by: Manuel Krause <[email protected]>
> Tested-by: szegad <[email protected]>
> Tested-by: prash <[email protected]>
> Tested-by: amish <[email protected]>
> Signed-off-by: Zhang Rui <[email protected]>
> Signed-off-by: Chen Yu <[email protected]>
> ---
> drivers/thermal/thermal_core.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index c3bdb48..09c78a4 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -1450,6 +1450,7 @@ __thermal_cooling_device_register(struct device_node
> *np,
> const struct thermal_cooling_device_ops *ops)
> {
> struct thermal_cooling_device *cdev;
> + struct thermal_instance *pos, *next;
> int result;
>
> if (type && strlen(type) >= THERMAL_NAME_LENGTH)
> @@ -1494,6 +1495,15 @@ __thermal_cooling_device_register(struct device_node
> *np,
> /* Update binding information for 'this' new cdev */
> bind_cdev(cdev);
>
I think you need to hold cdev->lock here, to make sure that no thermal
zone is added or removed from cdev->thermal_instances while you are looping.
> + list_for_each_entry_safe(pos, next, &cdev->thermal_instances,
> cdev_node) {
Why list_for_each_entry_safe() ? You are not going to remove any
entry, so you can just use list_for_each_entry()
> + if (next->cdev_node.next == &cdev->thermal_instances) {
> + thermal_zone_device_update(next->tz);
> + break;
> + }
> + if (pos->tz != next->tz)
> + thermal_zone_device_update(pos->tz);
> + }
Why is this so complicated? Can't you just do:
list_for_each_entry(pos, &cdev->thermal_instances, cdev_node)
thermal_zone_device_update(pos->tz);
Cheers,
Javi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
