linux/include
Jason Baron 346e15beb5 driver core: basic infrastructure for per-module dynamic debug messages
Base infrastructure to enable per-module debug messages.

I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes
control of debugging statements on a per-module basis in one /proc file,
currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG,
is not set, debugging statements can still be enabled as before, often by
defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no
affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set.

The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That
is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls
can be dynamically enabled/disabled on a per-module basis.

Future plans include extending this functionality to subsystems, that define 
their own debug levels and flags.

Usage:

Dynamic debugging is controlled by the debugfs file, 
<debugfs>/dynamic_printk/modules. This file contains a list of the modules that
can be enabled. The format of the file is as follows:

	<module_name> <enabled=0/1>
		.
		.
		.

	<module_name> : Name of the module in which the debug call resides
	<enabled=0/1> : whether the messages are enabled or not

For example:

	snd_hda_intel enabled=0
	fixup enabled=1
	driver enabled=0

Enable a module:

	$echo "set enabled=1 <module_name>" > dynamic_printk/modules

Disable a module:

	$echo "set enabled=0 <module_name>" > dynamic_printk/modules

Enable all modules:

	$echo "set enabled=1 all" > dynamic_printk/modules

Disable all modules:

	$echo "set enabled=0 all" > dynamic_printk/modules

Finally, passing "dynamic_printk" at the command line enables
debugging for all modules. This mode can be turned off via the above
disable command.

[gkh: minor cleanups and tweaks to make the build work quietly]

Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:47 -07:00
..
acpi
asm-arm
asm-cris Remove asm/a.out.h files for all architectures without a.out support. 2008-09-06 19:30:24 +01:00
asm-frv
asm-generic driver core: basic infrastructure for per-module dynamic debug messages 2008-10-16 09:24:47 -07:00
asm-m32r Remove asm/a.out.h files for all architectures without a.out support. 2008-09-06 19:30:24 +01:00
asm-m68k m68k: remove the dead PCI code 2008-10-14 10:23:27 -07:00
asm-mn10300
asm-parisc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-10-13 17:13:56 +01:00
asm-um net: Fix build with ARCH=um 2008-09-19 12:44:54 -07:00
asm-x86 Merge git://git.infradead.org/users/dwmw2/random-2.6 2008-10-13 09:59:14 -07:00
asm-xtensa Remove asm/a.out.h files for all architectures without a.out support. 2008-09-06 19:30:24 +01:00
crypto crypto: rng - RNG interface and implementation 2008-08-29 15:50:04 +10:00
drm
keys
linux driver core: basic infrastructure for per-module dynamic debug messages 2008-10-16 09:24:47 -07:00
math-emu math-emu: Add support for reporting exact invalid exception 2008-09-16 10:01:37 -05:00
media V4L/DVB (9168): Add support for MSI TV@nywhere Plus remote 2008-10-13 09:57:34 -02:00
mtd
net Merge branch 'next' into for-linus 2008-10-13 09:35:14 +11:00
pcmcia pcmcia: ioctl-internal definitions 2008-08-31 16:00:42 +02:00
rdma
rxrpc
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2008-10-10 10:53:26 -07:00
sound Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2008-10-13 14:03:59 -07:00
video Merge branch 'pxa-all' into devel 2008-10-09 21:33:02 +01:00
xen xen: remove unused balloon.h 2008-10-03 10:04:10 +02:00
Kbuild