Re: [PATCH v1 2/2] mm/damon/sysfs: use kzmalloc instead kmalloc to simplify codes

SeongJae Park
2022-09-20T16:25:52Z

Hi Xin,

On Tue, 20 Sep 2022 09:58:41 +0800 haoxin <xhao@linux.alibaba.com> wrote:

>
> 在 2022/9/20 上午1:22, SeongJae Park 写道:
> > On Mon, 19 Sep 2022 23:12:01 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:
> >
> >> In damon_sysfs_access_pattern_alloc() adn damon_sysfs_attrs_alloc(),
> >> we can use kzmalloc to alloc instance of the related structs, This makes
> >> the function code much cleaner.
> > This definitely makes the code cleaner, thank you. But, the initial intent of
> > the code is to initialize the fiedls that really need to be initialized at the
> > point, for the efficiency and also for making it clear which field is needed to
> > be initialized to what value here. It's also intended to make readers wonder
> > about where and how the remaining fields are initialized.
>
> Maybe the other func like damon_sysfs_kdamonds_alloc() also need to do
> like this, you can see it return directly by
>
> kzalloc.
>
> static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void)
> {
> return kzalloc(sizeof(struct damon_sysfs_kdamonds),
> GFP_KERNEL);
> }

In this case, all the fields of the struct need to be initialized as zero.
That's why we use kzalloc() there.

Of course, my opinion is not a static and concrete rule, but changing mind.
And obviously everyone makes many mistakes and DAMON code has many rooms for
improvement. I really appreciate for your greatful efforts for that. But, at
least in this case, I think it doesn't really need the change at the moment,
IMHO.

Thanks,
SJ …