Dynamic Debug: Introduce ddebug_query= boot parameter

Dynamic debug lacks the ability to enable debug messages at boot time.
One could patch initramfs or service startup scripts to write to
/sys/../dynamic_debug/control, but this sucks.

This patch makes it possible to pass a query in the same format one can
write to /sys/../dynamic_debug/control via boot param.
When dynamic debug gets initialized, this query will automatically be
applied.


Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: jbaron@redhat.com
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Thomas Renninger
2010-08-06 16:11:02 +02:00
committed by Greg Kroah-Hartman
parent fd89cfb871
commit a648ec05bb
3 changed files with 52 additions and 2 deletions

View File

@ -43,10 +43,11 @@ parameter is applicable:
AVR32 AVR32 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
DRM Direct Rendering Management support is enabled.
EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
EFI EFI Partitioning (GPT) is enabled
EIDE EIDE/ATAPI support is enabled.
DRM Direct Rendering Management support is enabled.
DYNAMIC_DEBUG Build in debug messages and enable them at runtime
FB The frame buffer device is enabled.
GCOV GCOV profiling is enabled.
HW Appropriate hardware is enabled.
@ -570,6 +571,10 @@ and is between 256 and 4096 characters. It is defined in the file
Format: <port#>,<type>
See also Documentation/input/joystick-parport.txt
ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot
time. See Documentation/dynamic-debug-howto.txt for
details.
debug [KNL] Enable kernel debugging (events log level).
debug_locks_verbose=