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Date:   Thu, 16 Nov 2023 00:16:34 -0500
MIME-Version: 1.0
Subject: Re: [PATCH 3/3] bpf: bpf_iter_task_next: use next_task(kit->task)
 rather than next_task(kit->pos)
Content-Language: en-GB
To:     Oleg Nesterov <oleg@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>
Cc:     Chuyi Zhou <zhouchuyi@bytedance.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Kui-Feng Lee <kuifeng@fb.com>, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org
References: <20231114163239.GA903@redhat.com>
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From:   Yonghong Song <yonghong.song@linux.dev>
In-Reply-To: <20231114163239.GA903@redhat.com>
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On 11/14/23 11:32 AM, Oleg Nesterov wrote:
> This looks more clear and simplifies the code. While at it, remove the
> unnecessary initialization of pos/task at the start of bpf_iter_task_new().
>
> Note that we can even kill kit->task, we can just use pos->group_leader,
> but I don't understand the BUILD_BUG_ON() checks in bpf_iter_task_new().

Let us keep kit->task, which is used in later function
bpf_iter_task_next(). The patch looks good to me.

>
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Acked-by: Yonghong Song <yonghong.song@linux.dev>