Re: [PATCH v1 1/2] mm/damon/sysfs: remove unnecessary variables

[haoxin]

在 2022/9/20 上午1:03, SeongJae Park 写道:
> On Mon, 19 Sep 2022 23:12:00 +0800 Xin Hao <xhao@xxxxxxxxxxxxxxxxx> wrote:
>
> > Just do a little change here, the 'err' variable really no need to stay
> > here.
> >
> > Signed-off-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>
> > ---
> >   mm/damon/sysfs.c | 6 ++----
> >   1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
> > index 0cca1909bf67..b852a75b9f39 100644
> > --- a/mm/damon/sysfs.c
> > +++ b/mm/damon/sysfs.c
> > @@ -1109,9 +1109,8 @@ static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr,
> >   {
> >   	struct damon_sysfs_region *region = container_of(kobj,
> >   			struct damon_sysfs_region, kobj);
> > -	int err = kstrtoul(buf, 0, &region->start);
> >
> > -	if (err)
> > +	if (kstrtoul(buf, 0, &region->start))
> >   		return -EINVAL;
> Good finding.  But, I'd like to let the user know why it really fails by giving
> them the error code that returned by 'kstrtoul()' here.  Let's keep the 'err'
> but return 'err' here.
Ok,  it make sense.
> >   	return count;
> >   }
> > @@ -1130,9 +1129,8 @@ static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr,
> >   {
> >   	struct damon_sysfs_region *region = container_of(kobj,
> >   			struct damon_sysfs_region, kobj);
> > -	int err = kstrtoul(buf, 0, &region->end);
> >
> > -	if (err)
> > +	if (kstrtoul(buf, 0, &region->end))
> >   		return -EINVAL;
> ditto.
>
> >   	return count;
> >   }
> > --
> > 2.31.0
>
> Thanks,
> SJ