From mboxrd@z Thu Jan 1 00:00:00 1970 From: martink@posteo.de (Martin Kepplinger) Date: Wed, 16 Apr 2014 13:57:07 +0200 Subject: loglevel 7 (debug) and =?UTF-8?Q?pr=5Fdebug=28=29?= In-Reply-To: References: <534E42C5.1040904@posteo.de> <534E4A86.1070004@posteo.de> <619a975e66956e4e35559bb2608cb961@posteo.de> Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Am 16.04.2014 13:43 schrieb Denis Pithon: > Martin, > > I'm not sure did you enable DDEBUG when compiling your module ? > pr_debug() macro is discarded if you omit DEBUG in compile time > > A sample Makefile which enable pr_debug() : > > obj-m += my_modue.o > > KDIR ?= /lib/modules/`uname -r`/build > CFLAGS_my_module.o := -DDEBUG > > all: > make -C $(KDIR) M=$(PWD) modules > > clean: > make -C $(KDIR) M=$(PWD) clean > > Let me know ... > regards Thanks, I did not, but now added -DDEBUG. The exact line is: CFLAGS_my_module.o := -DDEBUG when "my_module.o" is my object file. Did I get that right? That doesn't change anything unfortunately. I can not read pr_debug() unless I explicitely activate it in /sys/kernel/debug/dynamic_debug/control *after* insmod. I'd like to just read all pr_debug() messages like pr_info(). thanks for your time! > > On Wed, Apr 16, 2014 at 1:11 PM, Martin Kepplinger > wrote: > >> Am 16.04.2014 11:58 schrieb Arun KS: >> >>> Hi Martin, >>> >>> On Wed, Apr 16, 2014 at 2:46 PM, Martin Kepplinger >>> >>> wrote: >>>> Am 2014-04-16 11:00, schrieb Arun KS: >>>>> Hi Martin, >>> ?>> >>>>> On Wed, Apr 16, 2014 at 2:13 PM, Martin Kepplinger >>>>> wrote: >>>>>> I'm on Debian here and I don't really get pr_debug and >>>>>> printk(KERN_DEBUG >>> ?>>> ...). Let's stick to pr_debug. >>>>>> >>>>>> I have DYNAMIC_DEBUG enabled and >>>>>> root at laptop:/proc/sys/kernel# cat /proc/sys/kernel/printk >>>>>> 7 ? ? ? 7 ? ? ? 1 ? ? ? 7 >>> ?>> This shows the console log level. >>>>> This file controls the traffic to console. But all the log >>>>> messages >>>>> will be present in logbuf. >>>> >>>> How do I view debug messages from logbuf? >>> ?> >>>>> >>>>>> >>>>>> I write a module with pr_debug's. I load the module and I *don't* >>>>>> see >>>>>> anything in /var/log/messages (or anywhere in /var/log/* ). >>>>>> Adding >>>>>> #define DEBUG doesn't help. >>> ?>>> >>>>>> /sys/kernel/debug/dynamic_debug/control has the pr_debug entries >>>>>> I >>>>>> use >>>>>> in my loaded module. >>>>>> >>>>>> In short: How do I see debug log messages? Using pr_info() works >>>>>> as >>> ?>>> expected. What am I missing? Do I need to edit my Makefile? >>>>> Did you enable dynamic printing for your file? >>>>> >>>>> Below command enables dynamic printing for file sdhci.c. >>>>> echo 'file sdhci.c +p' > /sys/kernel/debug/dynamic_debug/control >>> ?> >>>> well. I tried that. The thing is, the pr_debug() symbols are in >>>> "control" only after "insmod my_module". Then I can echo -n 'file >>>> my_mobule.c +p' > control >>>> But my pr_debug() messages get printed directly after insmod, >>>> basically >>> ?> in my module_init function. Enabling my file doesn't output >>> anything in >>>> /var/log/* >>> So now you know why your pr_debug is absent in logbuf. >>> >>> You can make your module as a built in and use bootargs. >>> >>> eg: >>> dyndbg="file your_filename.c +p" >>> >>> Thanks, >>> Arun >>> >> >> So it's *not* possible at all to get pr_debug() messages just like >> pr_info() messages? >> Of what I've read, I assumed pr_debug() is just loglevel 7. >> >> thanks for your help! >> >>>> >>>>> >>>>> >>>>> Thanks, >>>>> Arun >>>>>> >>>>>> thanks! >>>>>> ? ? ? ? ? ? ? ? ? ? ?martin >>> ?>>> >>>>>> -- >>>>>> Martin Kepplinger >>>>>> e-mail ? ? ? ?martink AT posteo DOT at >>>>>> chat (XMPP) ? martink AT jabber DOT at >>>>>> >>>>>> _______________________________________________ >>> ?>>> Kernelnewbies mailing list >>>>>> Kernelnewbies at kernelnewbies.org >>>>>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies [1] >>>>>> [1] >> >>> ?>> >>>>> _______________________________________________ >>>>> Kernelnewbies mailing list >>>>> Kernelnewbies at kernelnewbies.org >>>>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies [1] >>>>> [1] >> >>> ?>> >>>> >>>> >>>> _______________________________________________ >>>> Kernelnewbies mailing list >>>> Kernelnewbies at kernelnewbies.org >>>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies [1] >>>> [1] >>> >>> Links: >>> ------ >>> [1] http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >>> [1] >> >>> >>> _______________________________________________ >>> Kernelnewbies mailing list >>> Kernelnewbies at kernelnewbies.org >>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies [1] >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies at kernelnewbies.org >> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies [1] > > > > Links: > ------ > [1] http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies