Re: [PATCH v2 01/11] thermal: core: Add and use thermal zone guard

[Lukasz Luba]

On 10/23/24 10:50, Rafael J. Wysocki wrote:
> Hi Lukasz,
>
> On Tue, Oct 22, 2024 at 11:01 PM Lukasz Luba <lukasz.luba@xxxxxxx> wrote:
> > Hi Rafael,
> >
> > On 10/10/24 23:05, Rafael J. Wysocki wrote:
> > > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > >
> > > Add and use a guard for thermal zone locking.
> > >
> > > This allows quite a few error code paths to be simplified among
> > > other things and brings in a noticeable code size reduction for
> > > a good measure.
> > >
> > > No intentional functional impact.
> > >
> > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > > ---
> > >
> > > This is a new iteration of
> > >
> > > https://lore.kernel.org/linux-pm/3241904.5fSG56mABF@xxxxxxxxxxxxx/
> > >
> > > that has been combined with
> > >
> > > https://lore.kernel.org/linux-pm/4613601.LvFx2qVVIh@xxxxxxxxxxxxx/
> > >
> > > and rebased on top of
> > >
> > > https://lore.kernel.org/linux-pm/12549318.O9o76ZdvQC@xxxxxxxxxxxxx/
> > >
> > > and
> > >
> > > https://lore.kernel.org/linux-pm/2215082.irdbgypaU6@xxxxxxxxxxxxx/
> > >
> > > ---
> > >    drivers/thermal/thermal_core.c    |   61 +++++++---------------------
> > >    drivers/thermal/thermal_core.h    |    4 +
> > >    drivers/thermal/thermal_debugfs.c |   25 +++++++----
> > >    drivers/thermal/thermal_helpers.c |   17 ++-----
> > >    drivers/thermal/thermal_hwmon.c   |    5 --
> > >    drivers/thermal/thermal_netlink.c |   21 ++-------
> > >    drivers/thermal/thermal_sysfs.c   |   81 ++++++++++++++++----------------------
> > >    drivers/thermal/thermal_trip.c    |    8 ---
> > >    8 files changed, 86 insertions(+), 136 deletions(-)
> >
> >
> > [snip]
> >
> > Surprise, how the code can look smaller using that
> > style with 'guard'.
>
> Yes, it gets more concise.
>
> Not only that, though.  It is also less error-prone, because you won't
> forget to unlock the lock in an error path and you won't use "lock"
> instead of "unlock" by mistake etc.
>
> Moreover, it kind of promotes dividing the code into smaller
> self-contained pieces, which is a plus too IMV.

I cannot agree more!