linux/kernel/printk
John Ogness 100bdef2c1 console: introduce wrappers to read/write console flags
After switching to SRCU for console list iteration, some readers
will begin readings console->flags as a data race. Locklessly
reading console->flags provides a consistent value because there
is at most one CPU modifying console->flags and that CPU is
using only read-modify-write operations.

Introduce a wrapper for SRCU iterators to read console flags.
Introduce a matching wrapper to write to flags of registered
consoles. Writing to flags of registered consoles is synchronized
by the console_list_lock.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-13-john.ogness@linutronix.de
2022-12-02 11:25:00 +01:00
..
braille.c printk: Replace strncmp() with str_has_prefix() 2019-08-16 09:54:08 +02:00
braille.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
console_cmdline.h printk: Fix preferred console selection with multiple matches 2020-02-18 09:34:42 +01:00
index.c printk: avoid -Wsometimes-uninitialized warning 2021-10-04 10:28:43 +02:00
internal.h Revert "printk: Wait for the global console lock when the system is going down" 2022-06-23 18:41:40 +02:00
Makefile printk: move printk sysctl to printk/sysctl.c 2022-01-22 08:33:35 +02:00
printk_ringbuffer.c printk: ringbuffer: Improve prb_next_seq() performance 2022-01-26 16:00:32 +01:00
printk_ringbuffer.h printk: ringbuffer: Improve prb_next_seq() performance 2022-01-26 16:00:32 +01:00
printk_safe.c Revert "printk: Wait for the global console lock when the system is going down" 2022-06-23 18:41:40 +02:00
printk.c console: introduce wrappers to read/write console flags 2022-12-02 11:25:00 +01:00
sysctl.c printk: Fix incorrect __user type in proc_dointvec_minmax_sysadmin() 2022-02-03 11:27:38 -08:00