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Message-ID: <1fadd74c-25d0-b9ab-8a06-27a9faa6579b@linaro.org>
Date:   Fri, 20 May 2022 09:56:50 -0700
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Subject: Re: [PATCH] cgroup: don't queue css_release_work if one already
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To:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>
Cc:     Tejun Heo <tj@kernel.org>, Hillf Danton <hdanton@sina.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        syzbot+e42ae441c3b10acf9e9d@syzkaller.appspotmail.com
References: <20220412192459.227740-1-tadeusz.struk@linaro.org>
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 <489592f6-b783-7bdb-2cc8-0c8e35ebc674@linaro.org>
 <20220520164255.GB17335@blackbody.suse.cz>
From:   Tadeusz Struk <tadeusz.struk@linaro.org>
In-Reply-To: <20220520164255.GB17335@blackbody.suse.cz>
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On 5/20/22 09:42, Michal Koutný wrote:
> On Fri, May 20, 2022 at 09:38:12AM -0700, Tadeusz Struk<tadeusz.struk@linaro.org>  wrote:
>> as this is a result of enqueuing the same css->destroy_work onto the same WQ,
>> one on the rcu path and one on the css_release path.
>> I will prototype it today and test with syzbot.
> In my understanding, you'd need two independent work_structs in a css,
> not two separate workqueues to put the single entry on.

I think either way would work, but two workqueues would be less churn.
I can try both.

-- 
Thanks,
Tadeusz