2024-04-09 18:44:43

by Thorsten Blum

Subject: [PATCH] MIPS: ralink: Use min() to fix Coccinelle warning

Fixes the following Coccinelle/coccicheck warning reported by
minmax.cocci:

WARNING opportunity for min()

Signed-off-by: Thorsten Blum <[email protected]>
---
arch/mips/ralink/timer.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/mips/ralink/timer.c b/arch/mips/ralink/timer.c
index 54094f6e033e..d271ac98312a 100644
--- a/arch/mips/ralink/timer.c
+++ b/arch/mips/ralink/timer.c
@@ -75,11 +75,7 @@ static int rt_timer_request(struct rt_timer *rt)

static int rt_timer_config(struct rt_timer *rt, unsigned long divisor)
{
- if (rt->timer_freq < divisor)
- rt->timer_div = rt->timer_freq;
- else
- rt->timer_div = divisor;
-
+ rt->timer_div = min(rt->timer_freq, divisor);
rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);

return 0;
--
2.44.0

2024-04-10 10:44:02

by Sergio Paracuellos

Subject: Re: [PATCH] MIPS: ralink: Use min() to fix Coccinelle warning

Hi Thorsten,

On Tue, Apr 9, 2024 at 5:36 PM Thorsten Blum <[email protected]> wrote:
>
> Fixes the following Coccinelle/coccicheck warning reported by
> minmax.cocci:
>
> WARNING opportunity for min()
>
> Signed-off-by: Thorsten Blum <[email protected]>
> ---
> arch/mips/ralink/timer.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/arch/mips/ralink/timer.c b/arch/mips/ralink/timer.c
> index 54094f6e033e..d271ac98312a 100644
> --- a/arch/mips/ralink/timer.c
> +++ b/arch/mips/ralink/timer.c
> @@ -75,11 +75,7 @@ static int rt_timer_request(struct rt_timer *rt)
>
> static int rt_timer_config(struct rt_timer *rt, unsigned long divisor)
> {
> - if (rt->timer_freq < divisor)
> - rt->timer_div = rt->timer_freq;
> - else
> - rt->timer_div = divisor;
> -
> + rt->timer_div = min(rt->timer_freq, divisor);

I do find the original code more readable.

Best regards,
Sergio Paracuellos

> rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
>
> return 0;
> --
> 2.44.0
>

2024-04-15 08:43:59

by David Laight

Subject: RE: [PATCH] MIPS: ralink: Use min() to fix Coccinelle warning

From: Sergio Paracuellos
> Sent: 10 April 2024 11:44
> On Tue, Apr 9, 2024 at 5:36 PM Thorsten Blum <[email protected]> wrote:
> >
> > Fixes the following Coccinelle/coccicheck warning reported by
> > minmax.cocci:
> >
> > WARNING opportunity for min()
> >
> > Signed-off-by: Thorsten Blum <[email protected]>
> > ---
> > arch/mips/ralink/timer.c | 6 +-----
> > 1 file changed, 1 insertion(+), 5 deletions(-)
> >
> > diff --git a/arch/mips/ralink/timer.c b/arch/mips/ralink/timer.c
> > index 54094f6e033e..d271ac98312a 100644
> > --- a/arch/mips/ralink/timer.c
> > +++ b/arch/mips/ralink/timer.c
> > @@ -75,11 +75,7 @@ static int rt_timer_request(struct rt_timer *rt)
> >
> > static int rt_timer_config(struct rt_timer *rt, unsigned long divisor)

I doubt 'unsigned long' is the best type there.
It should probably be u32 - so still 32bit on 64bit systems.

> > {
> > - if (rt->timer_freq < divisor)
> > - rt->timer_div = rt->timer_freq;
> > - else
> > - rt->timer_div = divisor;
> > -
> > + rt->timer_div = min(rt->timer_freq, divisor);
>
> I do find the original code more readable.

Probably because it isn't really a 'min()' but avoiding a division
generating a quotient of zero.
It might be better to explicitly avoid the x/x below.

David
>
> Best regards,
> Sergio Paracuellos
>
> > rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
> >
> > return 0;
> > --
> > 2.44.0
> >

-
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