user_mode(regs) macro in kernel

2012-06-20 Thread sumeet linux
Hi All, What is the meaning of user_mode(regs) macro ? What does it do ? This macro used in many files in kernel like signal.c, trap.c, process.c files. >From the code it looks like it checks is in USER mode or KERNEL mode, but still not clear on usage and implementation of this macro. Thanks.

Re: Some questions from a kernel newbie

2012-02-19 Thread sumeet linux
On Mon, Feb 20, 2012 at 10:33 AM, Royo Ruan wrote: > Hi All, > > I am a newbie from China. I want to fix some bugs for linux kernel > (current version or older versions), but this is my first time to join > community, I don't know how to start... Please help me answer the following > questions! :-

usage of _GPL

2012-01-19 Thread sumeet linux
Hi All, Can anyone clarify that when should I use _GPL and when not ? Is there a policy like for new code, it must be _GPL ? I see in kernel many places _GPL used like EXPORT_SYMBOL_GPL( ), but many places only EXPORT_SYMBOL( ). Regards, Sumeet ___ Kern

xx_initcall ( ) in kernel

2011-07-13 Thread sumeet linux
Dear friends, I want to know the basics xx_initcall ( ) in linux kernel. How this function works ? Observed in kernel code, many places late_initcall ( ), early_initcall ( ), arch_initcall ( ), core_initcall ( ) gets called. When did all these functions gets call during kernel initialization ? I a

Re: OS Books suggestion

2011-06-07 Thread sumeet linux
2011/6/2 Althaf > Have you had a look over here [1], though it is a bit outdated, it have > enough information to kickstart linux kernel, after that move on to > Understanding series from various authors. I highly recommend spending time > with Modern OS by AST inorder to get good idea on operati

Re: knewbies project? - updating LDD3 source

2011-05-25 Thread sumeet linux
On Wed, May 25, 2011 at 11:57 AM, Mohamed Thalib H wrote: > On Wednesday 25 May 2011 09:12 AM, naren.me...@gmail.com wrote: > >> Why not take this a little bit higher and rewrite the LDD3 book > >> > sections that need updating, not (only) the source code examples. > >> > > > This sounds like an

Re: demand based power management

2011-03-03 Thread sumeet linux
On Thu, Aug 12, 2010 at 8:50 PM, John Mahoney wrote: > On Thu, Aug 12, 2010 at 3:22 AM, er krishna wrote: >> Yes its fine, I am just wandering if this option is enabled by bios ? How ? > > In sys these values are listed on a per cpu basis. > > To list possible governors: > cat /sys/devices/system