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From:   SeongJae Park <sj@kernel.org>
To:     SeongJae Park <sj@kernel.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>, damon@lists.linux.dev,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 07/11] mm/damon/sysfs-schemes: connect filter directory and filters directory
Date:   Sun, 27 Nov 2022 18:22:54 +0000
Message-Id: <20221127182254.4850-1-sj@kernel.org>
In-Reply-To: <20221124212114.136863-8-sj@kernel.org>
References: 
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On Thu, 24 Nov 2022 21:21:10 +0000 SeongJae Park <sj@kernel.org> wrote:

> Implement 'nr_filters' file under 'filters' directory, which will be
> used to populate specific number of 'filter' directory under the
> directory, similar to other 'nr_*' files in DAMON sysfs interface.
> 
> Signed-off-by: SeongJae Park <sj@kernel.org>
> ---
>  mm/damon/sysfs-schemes.c | 67 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 67 insertions(+)
> 
> diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
> index afbfc55a8e84..7f2bab617156 100644
> --- a/mm/damon/sysfs-schemes.c
> +++ b/mm/damon/sysfs-schemes.c
[...]
> @@ -401,6 +407,57 @@ damon_sysfs_scheme_filters_alloc(void)
>  	return kzalloc(sizeof(struct damon_sysfs_scheme_filters), GFP_KERNEL);
>  }
>  
> +static void damon_sysfs_scheme_filters_rm_dirs(
> +		struct damon_sysfs_scheme_filters *filters)
> +{
> +	struct damon_sysfs_scheme_filter **filters_arr = filters->filters_arr;
> +	int i;
> +
> +	for (i = 0; i < filters->nr; i++)
> +		kobject_put(&filters_arr[i]->kobj);
> +	filters->nr = 0;
> +	kfree(filters_arr);
> +	filters->filters_arr = NULL;
> +}

This function should also be called from damon_Sysfs_scheme_rm_dirs() but this
patch is missing that.  This could result in undeleted filters directory when
writing 0 to 'nr_schemes' file.  Next version of this patchset will fix that.


Thanks,
SJ

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