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Date:   Wed, 13 Sep 2023 19:24:03 +0800
User-Agent: Mozilla Thunderbird
Subject: Re: [RFC PATCH v2 1/5] mm, oom: Introduce bpf_oom_evaluate_task
To:     Chuyi Zhou <zhouchuyi@bytedance.com>, hannes@cmpxchg.org,
        mhocko@kernel.org, roman.gushchin@linux.dev, ast@kernel.org,
        daniel@iogearbox.net, andrii@kernel.org, muchun.song@linux.dev
Cc:     bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
        wuyun.abel@bytedance.com, robin.lu@bytedance.com,
        Michal Hocko <mhocko@suse.com>
References: <20230810081319.65668-1-zhouchuyi@bytedance.com>
 <20230810081319.65668-2-zhouchuyi@bytedance.com>
From:   Bixuan Cui <cuibixuan@vivo.com>
In-Reply-To: <20230810081319.65668-2-zhouchuyi@bytedance.com>
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在 2023/8/10 16:13, Chuyi Zhou 写道:
> + +__weak noinline int bpf_oom_evaluate_task(struct task_struct *task, 
> struct oom_control *oc) +{ + return NO_BPF_POLICY; +} + 
> +BTF_SET8_START(oom_bpf_fmodret_ids) +BTF_ID_FLAGS(func, 
> bpf_oom_evaluate_task) +BTF_SET8_END(oom_bpf_fmodret_ids)
I have a question here, why use __weak? Is there other modules that can 
redefine bpf_oom_evaluate_task? why not use __bpf_kfunc 
(Documentation/bpf/kfuncs.rst) ?

Thanks
Bixuan Cui