linux_dsm_epyc7002/include
Tejun Heo 6fe29354be printk: implement support for extended console drivers
printk log_buf keeps various metadata for each message including its
sequence number and timestamp.  The metadata is currently available only
through /dev/kmsg and stripped out before passed onto console drivers.  We
want this metadata to be available to console drivers too so that console
consumers can get full information including the metadata and dictionary,
which among other things can be used to detect whether messages got lost
in transit.

This patch implements support for extended console drivers.  Consoles can
indicate that they want extended messages by setting the new CON_EXTENDED
flag and they'll be fed messages formatted the same way as /dev/kmsg.

 "<level>,<sequnum>,<timestamp>,<contflag>;<message text>\n"

If extended consoles exist, in-kernel fragment assembly is disabled.  This
ensures that all messages emitted to consoles have full metadata including
sequence number.  The contflag carries enough information to reassemble
the fragments from the reader side trivially.  Note that this only affects
/dev/kmsg.  Regular console and /proc/kmsg outputs are not affected by
this change.

* Extended message formatting for console drivers is enabled iff there
  are registered extended consoles.

* Comment describing /dev/kmsg message format updated to add missing
  contflag field and help distinguishing variable from verbatim terms.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:38 -07:00
..
acpi Merge branch 'acpi-cca' 2015-06-19 01:17:35 +02:00
asm-generic mm: clarify that the function operates on hugepage pte 2015-06-24 17:49:44 -07:00
clocksource
crypto crypto: rng - Do not free default RNG when it becomes unused 2015-06-22 15:49:18 +08:00
drm
dt-bindings Here is the bulk of pin control changes for the v4.2 series: 2015-06-24 19:21:02 -07:00
keys
kvm
linux printk: implement support for extended console drivers 2015-06-25 17:00:38 -07:00
math-emu
media
memory
misc cxl: Add AFU virtual PHB and kernel API 2015-06-03 13:27:20 +10:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-06-24 16:49:49 -07:00
pcmcia
ras tracing: add trace event for memory-failure 2015-06-24 17:49:43 -07:00
rdma IB/mad: Add final OPA MAD processing 2015-06-12 14:49:18 -04:00
rxrpc
scsi SCSI misc on 20150622 2015-06-23 15:55:44 -07:00
soc
sound ALSA: hda - Re-add the lost fake mute support 2015-06-11 11:55:48 +02:00
target SCSI misc on 20150622 2015-06-23 15:55:44 -07:00
trace Merge tag 'for-f2fs-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs 2015-06-24 20:38:29 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-06-24 16:49:49 -07:00
video video: fbdev: tdfxfb: use arch_phys_wc_add() and ioremap_wc() 2015-06-03 12:41:52 +03:00
xen
Kbuild