Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33;
Date:   Thu, 16 Nov 2023 10:38:48 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Yonghong Song <yonghong.song@linux.dev>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        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
Subject: Re: [PATCH 3/3] bpf: bpf_iter_task_next: use next_task(kit->task)
 rather than next_task(kit->pos)
Message-ID: <20231116093848.GB18748@redhat.com>
References: <20231114163239.GA903@redhat.com>
 <9dfbc7ce-49cc-4519-88cf-93d6b72e5ff6@linux.dev>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <9dfbc7ce-49cc-4519-88cf-93d6b72e5ff6@linux.dev>
User-Agent: Mutt/1.5.24 (2015-08-30)
Precedence: bulk

On 11/16, Yonghong Song wrote:
>
> 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.

Yes, but it can use pos->group_leader instead of kit->task.
But I agree, lets keep kit->task.

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

Thanks!

Oleg.