lkml.org 
[lkml]   [2022]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH printk 07/18] printk: Convert console list walks for readers to list lock
Date
From: Thomas Gleixner <tglx@linutronix.de>

Facilities which expose console information to sysfs or procfs can use the
new list protection to keep the list stable. No need to hold console lock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
---
drivers/tty/tty_io.c | 6 +++---
fs/proc/consoles.c | 6 +++---
kernel/printk/printk.c | 8 ++++----
3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 8fec1d8648f5..6fa142155b94 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -3535,8 +3535,8 @@ static ssize_t show_cons_active(struct device *dev,
struct console *c;
ssize_t count = 0;

- console_lock();
- for_each_console(c) {
+ console_list_lock();
+ for_each_registered_console(c) {
if (!c->device)
continue;
if (!c->write)
@@ -3560,7 +3560,7 @@ static ssize_t show_cons_active(struct device *dev,

count += sprintf(buf + count, "%c", i ? ' ':'\n');
}
- console_unlock();
+ console_list_unlock();

return count;
}
diff --git a/fs/proc/consoles.c b/fs/proc/consoles.c
index dfe6ce3505ce..6775056eecd5 100644
--- a/fs/proc/consoles.c
+++ b/fs/proc/consoles.c
@@ -63,8 +63,8 @@ static void *c_start(struct seq_file *m, loff_t *pos)
struct console *con;
loff_t off = 0;

- console_lock();
- for_each_console(con)
+ console_list_lock();
+ for_each_registered_console(con)
if (off++ == *pos)
break;

@@ -80,7 +80,7 @@ static void *c_next(struct seq_file *m, void *v, loff_t *pos)

static void c_stop(struct seq_file *m, void *v)
{
- console_unlock();
+ console_list_unlock();
}

static const struct seq_operations consoles_op = {
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 8c56f6071873..80a728ef9d96 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2990,18 +2990,18 @@ void console_flush_on_panic(enum con_flush_mode mode)
*/
struct tty_driver *console_device(int *index)
{
- struct console *c;
struct tty_driver *driver = NULL;
+ struct console *c;

- console_lock();
- for_each_console(c) {
+ console_list_lock();
+ for_each_registered_console(c) {
if (!c->device)
continue;
driver = c->device(c, index);
if (driver)
break;
}
- console_unlock();
+ console_list_unlock();
return driver;
}

--
2.30.2
\
 
 \ /
  Last update: 2022-09-24 02:05    [W:0.404 / U:0.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site