Re: [PATCH] drm/panthor: clean up some types in panthor_sched_suspend()

From: Boris Brezillon
Date: Wed Apr 17 2024 - 05:30:27 EST


On Mon, 8 Apr 2024 13:27:17 +0100
Steven Price <steven.price@xxxxxxx> wrote:

> On 08/04/2024 08:36, Dan Carpenter wrote:
> > These variables should be u32 instead of u64 because they're only
> > storing u32 values. Also static checkers complain when we do:
> >
> > suspended_slots &= ~upd_ctx.timedout_mask;
> >
> > In this code "suspended_slots" is a u64 and "upd_ctx.timedout_mask". The

'and "upd_ctx.timedout_mask" an u32.'?

> > mask clears out the top 32 bits which would likely be a bug if anything
> > were stored there.
> >
> > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>
> Reviewed-by: Steven Price <steven.price@xxxxxxx>

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>

>
> If you fancy a bit more clean-up then I think faulty_slots is completely
> redundant as a separate variable. In particular in the "if
> (suspended_slots)" section it's updated but that updated value is never
> used... otherwise I'll put it on my list for cleaning up later.

Yeah, I think this variable predates the upd_ctx stuff and is now useless.
I you post such a patch, please add my R-b directly.

Thanks,

Boris

>
> > ---
> > drivers/gpu/drm/panthor/panthor_sched.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> > index d4bc652b34d5..b3a51a6de523 100644
> > --- a/drivers/gpu/drm/panthor/panthor_sched.c
> > +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> > @@ -2546,7 +2546,7 @@ void panthor_sched_suspend(struct panthor_device *ptdev)
> > {
> > struct panthor_scheduler *sched = ptdev->scheduler;
> > struct panthor_csg_slots_upd_ctx upd_ctx;
> > - u64 suspended_slots, faulty_slots;
> > + u32 suspended_slots, faulty_slots;
> > struct panthor_group *group;
> > u32 i;
> >
>