Hi, Javi, > -----Original Message----- > From: Javi Merino [mailto:javi.merino@xxxxxxx] > Sent: Monday, September 28, 2015 10:29 PM > To: Chen, Yu C > Cc: linux-pm@xxxxxxxxxxxxxxx; edubezval@xxxxxxxxx; Zhang, Rui; linux- > kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 3/3] Thermal: do thermal zone update after a cooling > device registered > > On Sun, Sep 27, 2015 at 06:48:44AM +0100, Chen Yu wrote: > > From: Zhang Rui <rui.zhang@xxxxxxxxx> > > > > > > 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. > Ah right, will add. If I add the cdev ->lock here, will there be a AB-BA lock with thermal_zone_unbind_cooling_device? > > Why list_for_each_entry_safe() ? You are not going to remove any entry, so > you can just use list_for_each_entry() > > > 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); > This is an optimization here: Ignore thermal instance that refers to the same thermal zone in this loop, this works because bind_cdev() always binds the cooling device to one thermal zone first, and then binds to the next thermal zone. Best Regards, Yu ��.n��������+%������w��{.n�����������ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f