login
Header Space

 
 

[patch 0/3] dynamic printk

Score:
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: <linux-kernel@...>
Date: Tuesday, April 1, 2008 - 3:48 pm

hi,

Add the ability to dynamically enable/disable pr_debug()/dev_dbg() in the
kernel. Yes, these calls could be converted to printk(KERN_DEBUG), but there
are enough to cause overhead. Additionally, the logs become difficult to read.
Here, one can turn on and off these messages per .c source file via:

echo "add file.c" > /sys/kernel/debug/dynamic_printk/files
echo "remove file.c" > /sys/kernel/debug/dynamic_printk/files

There is also a special 'all' value that turns on all the debugging messages.

I hope that these patches are useful for people writing new kernel code, for
system debugging and testing. In enabling the 'all' feature on the kernel I was
running i got a bunch of messages... (i'm not sure what they mean, but they
could point out an error or a kernel optimization that could be made, which I 
didn't necessarily know about otherwise).

thanks,

-Jason

Apr  1 10:33:38 dhcp83-106 kernel: Already setup manip DST for ct ffff81007d800140
Apr  1 10:33:38 dhcp83-106 kernel: Already setup manip SRC for ct ffff81007d800140
Apr  1 10:33:38 dhcp83-106 kernel: Already setup manip DST for ct ffff81007d800a00
Apr  1 10:33:38 dhcp83-106 kernel: Already setup manip SRC for ct ffff81007d800a00
Apr  1 10:33:39 dhcp83-106 kernel: Already setup manip DST for ct ffff81007d800a00
Apr  1 10:33:39 dhcp83-106 kernel: Already setup manip SRC for ct ffff81007d800a00
Apr  1 10:33:39 dhcp83-106 kernel: Already setup manip DST for ct ffff81007d800a00
Apr  1 10:33:39 dhcp83-106 kernel: Already setup manip SRC for ct ffff81007d800a00
Apr  1 10:33:40 dhcp83-106 kernel: Already setup manip DST for ct ffff810071851dc0
Apr  1 10:33:40 dhcp83-106 kernel: Already setup manip SRC for ct ffff810071851dc0
Apr  1 10:33:40 dhcp83-106 kernel: Already setup manip DST for ct ffff81007d800a00
Apr  1 10:33:40 dhcp83-106 kernel: Already setup manip SRC for ct ffff81007d800a00


--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[patch 0/3] dynamic printk, Jason Baron, (Tue Apr 1, 3:48 pm)
speck-geostationary