Re: [PATCH v3 1/1] scsi: ufs: core: Support Updating UIC Command Timeout

[Bao D. Nguyen]

On 7/10/2024 10:46 PM, Bao D. Nguyen wrote:
> On 7/9/2024 11:10 AM, Bart Van Assche wrote:
> > On 7/8/24 11:06 PM, Bao D. Nguyen wrote:
> > > +static int uic_cmd_timeout_set(const char *val, const struct 
> > > kernel_param *kp)
> > > +{
> > > +    unsigned int n;
> > > +    int ret;
> > > +
> > > +    ret = kstrtou32(val, 0, &n);
> > > +    if (ret != 0 || n < UIC_CMD_TIMEOUT_DEFAULT || n > 
> > > UIC_CMD_TIMEOUT_MAX)
> > > +        return -EINVAL;
> > > +
> > > +    return param_set_int(val, kp);
> > > +}
> >
> > The above code converts 'val' twice to an integer: a first time by
> > calling kstrtou32() and a second time by calling param_set_int().
> > Please remove one of the two string-to-integer conversions, e.g. by
> > changing "param_set_int(val, kp)" into "uic_cmd_timeout = n" or
> > *(unsigned int *)kp->arg = n".
> Hi Bart,
> My understanding is that in the kstrtou32() function, the  the result of 
> the conversion is written to the third parameter only which is '&n' in 
> this case. 'val' does not get updated (and it cannot be updated because 
> of its 'const' type). Please correct me if I am wrong.
Hi Bart,
Maybe I misunderstood your comment. You probably was concerned about the 
execution time of param_set_int(val, kp) vs a single assignment 
instruction 'uic_cmd_timeout = n;', right? If that's the case, I'll 
update the patch.

Thanks, Bao

> Thanks, Bao
>
> > Thanks,
> >
> > Bart.