linux/include
Thomas Gleixner ecb5e1aa82 printk: nbcon: Implement emergency sections
In emergency situations (something has gone wrong but the
system continues to operate), usually important information
(such as a backtrace) is generated via printk(). This
information should be pushed out to the consoles ASAP.

Add per-CPU emergency nesting tracking because an emergency
can arise while in an emergency situation.

Add functions to mark the beginning and end of emergency
sections where the urgent messages are generated.

Perform direct console flushing at the emergency priority if
the current CPU is in an emergency state and it is safe to do
so.

Note that the emergency state is not system-wide. While one CPU
is in an emergency state, another CPU may attempt to print
console messages at normal priority.

Also note that printk() already attempts to flush consoles in
the caller context for normal priority. However, follow-up
changes will introduce printing kthreads, in which case the
normal priority printk() calls will offload to the kthreads.

Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-32-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
2024-08-21 15:03:04 +02:00
..
acpi ACPICA: Add a depth argument to acpi_execute_reg_methods() 2024-08-13 13:44:57 +02:00
asm-generic runtime constants: deal with old decrepit linkers 2024-08-03 08:38:45 -07:00
clocksource
crypto
drm drm/buddy: Add start address support to trim function 2024-08-07 18:19:00 -04:00
dt-bindings I3C for 6.11 2024-07-27 10:53:06 -07:00
keys
kunit
kvm
linux printk: nbcon: Implement emergency sections 2024-08-21 15:03:04 +02:00
math-emu
media
memory
misc
net vsock: fix recursive ->recvmsg calls 2024-08-15 12:07:04 +02:00
pcmcia
ras mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND 2024-07-12 15:52:22 -07:00
rdma
rv
scsi Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00
soc sound updates for 6.11-rc1 2024-07-19 12:39:34 -07:00
sound ASoC: Fixes for v6.11 2024-08-09 09:58:07 +02:00
target
trace vfs-6.11-rc4.fixes 2024-08-14 09:06:28 -07:00
uapi Char/Misc fixes for 6.11-rc4 2024-08-18 10:16:34 -07:00
ufs scsi: ufs: core: Check LSDBS cap when !mcq 2024-07-15 22:51:06 -04:00
vdso Random number generator updates for Linux 6.11-rc1. 2024-07-24 10:29:50 -07:00
video
xen Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00