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[93.147.243.58]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-58e2f7c0e00sm1410611a12.6.2024.07.04.14.55.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Jul 2024 14:55:19 -0700 (PDT) From: Jiri Olsa X-Google-Original-From: Jiri Olsa Date: Thu, 4 Jul 2024 23:55:16 +0200 To: Dan Carpenter Cc: Yonghong Song , Christian Brauner , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH bpf-next] bpf: remove unnecessary loop in task_file_seq_get_next() Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Jul 04, 2024 at 10:19:19AM -0500, Dan Carpenter wrote: > After commit 0ede61d8589c ("file: convert to SLAB_TYPESAFE_BY_RCU") this > loop always iterates exactly one time. Delete the for statement and pull > the code in a tab. > > Signed-off-by: Dan Carpenter lgtm Acked-by: Jiri Olsa jirka > --- > kernel/bpf/task_iter.c | 9 +++------ > 1 file changed, 3 insertions(+), 6 deletions(-) > > diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c > index ec4e97c61eef..02aa9db8d796 100644 > --- a/kernel/bpf/task_iter.c > +++ b/kernel/bpf/task_iter.c > @@ -261,6 +261,7 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info) > u32 saved_tid = info->tid; > struct task_struct *curr_task; > unsigned int curr_fd = info->fd; > + struct file *f; > > /* If this function returns a non-NULL file object, > * it held a reference to the task/file. > @@ -286,12 +287,8 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info) > } > > rcu_read_lock(); > - for (;; curr_fd++) { > - struct file *f; > - f = task_lookup_next_fdget_rcu(curr_task, &curr_fd); > - if (!f) > - break; > - > + f = task_lookup_next_fdget_rcu(curr_task, &curr_fd); > + if (f) { > /* set info->fd */ > info->fd = curr_fd; > rcu_read_unlock(); > -- > 2.43.0 >