bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Song Liu <songliubraving@fb.com>
To: <bpf@vger.kernel.org>, <netdev@vger.kernel.org>
Cc: <kernel-team@fb.com>, <ast@kernel.org>, <daniel@iogearbox.net>,
	<andrii@kernel.org>, <kpsingh@chromium.org>,
	<john.fastabend@gmail.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>
Subject: [PATCH bpf-next] bpf: simplify task_file_seq_get_next()
Date: Thu, 19 Nov 2020 16:28:33 -0800	[thread overview]
Message-ID: <20201120002833.2481110-1-songliubraving@fb.com> (raw)

Simplify task_file_seq_get_next() by removing two in/out arguments: task
and fstruct. Use info->task and info->files instead.

Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/task_iter.c | 53 ++++++++++++++----------------------------
 1 file changed, 17 insertions(+), 36 deletions(-)

diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c
index 1fdb2fc196cd9..7e15ca802988a 100644
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c
@@ -136,8 +136,7 @@ struct bpf_iter_seq_task_file_info {
 };
 
 static struct file *
-task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info,
-		       struct task_struct **task, struct files_struct **fstruct)
+task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info)
 {
 	struct pid_namespace *ns = info->common.ns;
 	u32 curr_tid = info->tid, max_fds;
@@ -150,14 +149,17 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info,
 	 * Otherwise, it does not hold any reference.
 	 */
 again:
-	if (*task) {
-		curr_task = *task;
-		curr_files = *fstruct;
+	if (info->task) {
+		curr_task = info->task;
+		curr_files = info->files;
 		curr_fd = info->fd;
 	} else {
 		curr_task = task_seq_get_next(ns, &curr_tid, true);
-		if (!curr_task)
+		if (!curr_task) {
+			info->task = NULL;
+			info->files = NULL;
 			return NULL;
+		}
 
 		curr_files = get_files_struct(curr_task);
 		if (!curr_files) {
@@ -168,8 +170,8 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info,
 		}
 
 		/* set *fstruct, *task and info->tid */
-		*fstruct = curr_files;
-		*task = curr_task;
+		info->files = curr_files;
+		info->task = curr_task;
 		if (curr_tid == info->tid) {
 			curr_fd = info->fd;
 		} else {
@@ -199,8 +201,8 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info,
 	rcu_read_unlock();
 	put_files_struct(curr_files);
 	put_task_struct(curr_task);
-	*task = NULL;
-	*fstruct = NULL;
+	info->task = NULL;
+	info->files = NULL;
 	info->fd = 0;
 	curr_tid = ++(info->tid);
 	goto again;
@@ -209,21 +211,13 @@ task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info,
 static void *task_file_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	struct bpf_iter_seq_task_file_info *info = seq->private;
-	struct files_struct *files = NULL;
-	struct task_struct *task = NULL;
 	struct file *file;
 
-	file = task_file_seq_get_next(info, &task, &files);
-	if (!file) {
-		info->files = NULL;
-		info->task = NULL;
-		return NULL;
-	}
-
-	if (*pos == 0)
+	info->task = NULL;
+	info->files = NULL;
+	file = task_file_seq_get_next(info);
+	if (file && *pos == 0)
 		++*pos;
-	info->task = task;
-	info->files = files;
 
 	return file;
 }
@@ -231,24 +225,11 @@ static void *task_file_seq_start(struct seq_file *seq, loff_t *pos)
 static void *task_file_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	struct bpf_iter_seq_task_file_info *info = seq->private;
-	struct files_struct *files = info->files;
-	struct task_struct *task = info->task;
-	struct file *file;
 
 	++*pos;
 	++info->fd;
 	fput((struct file *)v);
-	file = task_file_seq_get_next(info, &task, &files);
-	if (!file) {
-		info->files = NULL;
-		info->task = NULL;
-		return NULL;
-	}
-
-	info->task = task;
-	info->files = files;
-
-	return file;
+	return task_file_seq_get_next(info);
 }
 
 struct bpf_iter__task_file {
-- 
2.24.1


             reply	other threads:[~2020-11-20  0:29 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-20  0:28 Song Liu [this message]
2020-11-20 16:57 ` [PATCH bpf-next] bpf: simplify task_file_seq_get_next() Yonghong Song
2020-11-20 22:19 ` Daniel Borkmann

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201120002833.2481110-1-songliubraving@fb.com \
    --to=songliubraving@fb.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=john.fastabend@gmail.com \
    --cc=kernel-team@fb.com \
    --cc=kpsingh@chromium.org \
    --cc=netdev@vger.kernel.org \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).