From: John Ogness <john.ogness@linutronix.de>
To: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>,
Steven Rostedt <rostedt@goodmis.org>,
Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org, Richard Weinberger <richard@nod.at>,
Anton Ivanov <anton.ivanov@cambridgegreys.com>,
Johannes Berg <johannes@sipsolutions.net>,
linux-um@lists.infradead.org
Subject: [PATCH printk v2 20/38] um: kmsg_dumper: use srcu console list iterator
Date: Wed, 19 Oct 2022 17:01:42 +0206 [thread overview]
Message-ID: <20221019145600.1282823-21-john.ogness@linutronix.de> (raw)
In-Reply-To: <20221019145600.1282823-1-john.ogness@linutronix.de>
Rather than using the console_lock to guarantee safe console list
traversal, use srcu console list iteration.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
arch/um/kernel/kmsg_dump.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c
index 3a3bbbb22090..44a418dec919 100644
--- a/arch/um/kernel/kmsg_dump.c
+++ b/arch/um/kernel/kmsg_dump.c
@@ -16,20 +16,17 @@ static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
struct console *con;
unsigned long flags;
size_t len = 0;
+ int cookie;
/* only dump kmsg when no console is available */
- if (!console_trylock())
- return;
-
- for_each_console(con) {
+ cookie = console_srcu_read_lock();
+ for_each_console_srcu(con) {
if (strcmp(con->name, "tty") == 0 &&
(console_is_enabled(con) || (con->flags & CON_CONSDEV))) {
break;
}
}
-
- console_unlock();
-
+ console_srcu_read_unlock(cookie);
if (con)
return;
--
2.30.2
_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um
next prev parent reply other threads:[~2022-10-19 15:11 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-19 14:55 [PATCH printk v2 00/38] reduce console_lock scope John Ogness
2022-10-19 14:55 ` [PATCH printk v2 07/38] um: kmsg_dump: use console_is_enabled() John Ogness
2022-10-21 12:46 ` Petr Mladek
2022-10-19 14:55 ` John Ogness [this message]
2022-10-21 14:56 ` [PATCH printk v2 20/38] um: kmsg_dumper: use srcu console list iterator Petr Mladek
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=20221019145600.1282823-21-john.ogness@linutronix.de \
--to=john.ogness@linutronix.de \
--cc=anton.ivanov@cambridgegreys.com \
--cc=johannes@sipsolutions.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-um@lists.infradead.org \
--cc=pmladek@suse.com \
--cc=richard@nod.at \
--cc=rostedt@goodmis.org \
--cc=senozhatsky@chromium.org \
--cc=tglx@linutronix.de \
/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).