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Reply-To: yonghong.song@linux.dev
Subject: Re: [PATCH] bpf: task_group_seq_get_next: cleanup the usage of
 get/put_task_struct
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To: Oleg Nesterov <oleg@redhat.com>, Yonghong Song <yhs@fb.com>,
 Kui-Feng Lee <kuifeng@fb.com>, Andrii Nakryiko <andrii@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
 Martin KaFai Lau <martin.lau@kernel.org>, bpf@vger.kernel.org,
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References: <20230821150909.GA2431@redhat.com>
 <20230821200311.GA22497@redhat.com>
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On 8/21/23 1:03 PM, Oleg Nesterov wrote:
> get_pid_task() makes no sense, the code does put_task_struct() soon after.
> Use find_task_by_pid_ns() instead of find_pid_ns + get_pid_task and kill
> kill put_task_struct(), this allows to do get_task_struct() only once

remove the duplicated 'kill' in the above.

> before return.
> 
> While at it, kill the unnecessary "if (!pid)" check in the "if (!*tid)"
> block, this matches the next usage of find_pid_ns() + get_pid_task() in
> this function.
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

LGTM.

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