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Date:   Wed, 14 Sep 2022 10:26:38 +0000
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From:   "Yajun Deng" <yajun.deng@linux.dev>
Message-ID: <78c7cd3900e0a33da514be8799b35f9f@linux.dev>
Subject: Re: [PATCH] mm/damon: fix missing damon_del_region()
To:     "SeongJae Park" <sj@kernel.org>
Cc:     akpm@linux-foundation.org, sieberf@amazon.com, shakeelb@google.com,
        foersleo@amazon.de, damon@lists.linux.dev, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
In-Reply-To: <20220914095206.70459-1-sj@kernel.org>
References: <20220914095206.70459-1-sj@kernel.org>
Precedence: bulk

September 14, 2022 5:52 PM, "SeongJae Park" <sj@kernel.org> wrote:=0A=0A>=
 Hi Yajun,=0A> =0A> On Wed, 14 Sep 2022 17:36:36 +0800 Yajun Deng <yajun.=
deng@linux.dev> wrote:=0A> =0A>> It should be called damon_del_region() b=
efore free each region, so use=0A>> damon_destroy_region() instead of dam=
on_free_region().=0A> =0A> What 'damon_del_region()' does is deleting the=
 region from target's regions=0A> linked list so that nobody references i=
t later after its freed. However, as=0A> each region is linked to one tar=
get, and as we will free the target here, the=0A> list will also be freed=
. Therefore, we don't need to worry about future=0A> references to the re=
gion.=0A> =0A> Anything I'm missing?=0A> =0AOK, got it.=0A=0A> Thanks,=0A=
> SJ=0A> =0A>> Fixes: f23b8eee1871 (mm/damon/core: implement region-based=
 sampling)=0A>> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>=0A>> ---=
=0A>> mm/damon/core.c | 2 +-=0A>> 1 file changed, 1 insertion(+), 1 delet=
ion(-)=0A>> =0A>> diff --git a/mm/damon/core.c b/mm/damon/core.c=0A>> ind=
ex 0b1eb945c68a..e62e7ebf4b12 100644=0A>> --- a/mm/damon/core.c=0A>> +++ =
b/mm/damon/core.c=0A>> @@ -361,7 +361,7 @@ void damon_free_target(struct =
damon_target *t)=0A>> struct damon_region *r, *next;=0A>> =0A>> damon_for=
_each_region_safe(r, next, t)=0A>> - damon_free_region(r);=0A>> + damon_d=
estroy_region(r, t);=0A>> kfree(t);=0A>> }=0A>> =0A>> --=0A>> 2.25.1