Re: [OOT] Link to my Linux.com "Uncover the meaning of top's statistics"

2009-09-09 Thread Peter Teoh
definitely not OOT.my comment: when a task is going to 100% CPU utilizationperhaps u can do a "echo t > /proc/sysrq-trigger", which immediately can show the CURRENT stack trace of all task in dmesg (truncated, so look into /var/log/messages for full dump). "CURRENT" is important, as it i

Re: interrupt/tasklet issue in custom driver on recent kernels

2009-09-09 Thread Peter Teoh
How about this: use "top" to confirm which process is the one causing the 100% CPU utilization? Then enter "echo t > /proc/sysrq-trigger" to generate a stack trace dump of all the kernel threads. It should overflow your dmesg buffer, so look into /var/log/messages for the complete trace. And i

Re: [NEWBIE]

2009-09-09 Thread er krishna
ED, Can you just tell how to use this script for searching efficiently. I tried like : script.sh task_struct. Anything more if you want to add in this. Krishna On Wed, Sep 9, 2009 at 7:51 PM, Ed Cashin wrote: > Deven writes: > > > Hi, > > > > On Tue, 2009-09-08 at 19:01 +0530, Chandraka

Re: difference bigphysarea patch and kmalloc

2009-09-09 Thread Sven-Maurice Althoff
thanks again. ;-) On Wednesday 09 September 2009 18:15:11 you wrote: > Hi Mosta... > > On Wed, Sep 9, 2009 at 10:51 PM, mosta wrote: > > hey everyone, > > > > is there a difference between kmalloc(size, GFP_KERNEL | GFP_DMA) and > > bigphysarea_alloc (size). I god a driver that use the bigphysarea

Re: new kernel newbie column is up

2009-09-09 Thread Robert P. J. Day
On Wed, 9 Sep 2009, Mulyadi Santosa wrote: > On Wed, Sep 9, 2009 at 11:04 PM, Robert P. J. Day > wrote: > > > >  for various reasons, i skipped a week, but i like to think this > > week's column -- part 3 of 3 of sequence files -- makes up for it. > > it hurt to write.  make sure you ask question

Re: new kernel newbie column is up

2009-09-09 Thread Mulyadi Santosa
On Wed, Sep 9, 2009 at 11:04 PM, Robert P. J. Day wrote: > >  for various reasons, i skipped a week, but i like to think this > week's column -- part 3 of 3 of sequence files -- makes up for it. > it hurt to write.  make sure you ask questions in the comments > section. > >  http://cli.gs/ShyJXz >

new kernel newbie column is up

2009-09-09 Thread Robert P. J. Day
for various reasons, i skipped a week, but i like to think this week's column -- part 3 of 3 of sequence files -- makes up for it. it hurt to write. make sure you ask questions in the comments section. http://cli.gs/ShyJXz rday -- ===

Re: difference bigphysarea patch and kmalloc

2009-09-09 Thread Mulyadi Santosa
Hi Mosta... On Wed, Sep 9, 2009 at 10:51 PM, mosta wrote: > hey everyone, > > is there a difference between kmalloc(size, GFP_KERNEL | GFP_DMA) and > bigphysarea_alloc (size). I god a driver that use the bigphysarea patch and I > changed it to use kmalloc (because for my kernel version there is no

difference bigphysarea patch and kmalloc

2009-09-09 Thread mosta
hey everyone, is there a difference between kmalloc(size, GFP_KERNEL | GFP_DMA) and bigphysarea_alloc (size). I god a driver that use the bigphysarea patch and I changed it to use kmalloc (because for my kernel version there is no patch) and it worked. So my question is, is the bigphysarea patc

Re: [NEWBIE]

2009-09-09 Thread Samudra Vishvajith
Chandrakant Kumar wrote: > Hello > > I'm a computer science student . I am studying operating systems in the > current semester , so i got a chance to study about linux. I want to > learn kernel programming. may you people please tell me what materials > and books i should go through. please provid

Re: [NEWBIE]

2009-09-09 Thread Ed Cashin
Deven writes: > Hi, > > On Tue, 2009-09-08 at 19:01 +0530, Chandrakant Kumar wrote: >> Hello >> >> I'm a computer science student . I am studying operating systems in the >> current semester , so i got a chance to study about linux. I want to >> learn kernel programming. may you people please te

Re: interrupt/tasklet issue in custom driver on recent kernels

2009-09-09 Thread Jason Nymble
On 09 Sep 2009, at 3:47 PM, Mulyadi Santosa wrote: Hi Jason... On Wed, Sep 9, 2009 at 3:39 PM, Jason Nymble wrote: Hi, Background: We use a custom kernel driver module for our PCIe device which processes bulk data between the host and the card. The card issues MSI interrupts at up to 2

Re: interrupt/tasklet issue in custom driver on recent kernels

2009-09-09 Thread Mulyadi Santosa
Hi Jason... On Wed, Sep 9, 2009 at 3:39 PM, Jason Nymble wrote: > Hi, > > Background: We use a custom kernel driver module for our PCIe device which > processes bulk data between the host and the card. The card issues MSI > interrupts at up to 20kHz to the host, and the driver interrupt routine >

Re: Why there is no realloc in kernel?

2009-09-09 Thread vinit dhatrak
On Wed, Sep 9, 2009 at 5:13 PM, Leonidas . wrote: > Why there is no realloc in kernel? > Any specific reason? > > Regards, > Sandeep. > May be because it is not guaranteed that you will be able to allocate more than a page of kernel memory contiguously, you may need to be explicitly aware of the li

Why there is no realloc in kernel?

2009-09-09 Thread Leonidas .
Why there is no realloc in kernel? Any specific reason? Regards, Sandeep.

interrupt/tasklet issue in custom driver on recent kernels

2009-09-09 Thread Jason Nymble
Hi, Background: We use a custom kernel driver module for our PCIe device which processes bulk data between the host and the card. The card issues MSI interrupts at up to 20kHz to the host, and the driver interrupt routine essentially just calls tasklet_schedule() and returns IRQ_HANDLED,

PMEM device

2009-09-09 Thread Shankar Ganesh
Hi , I have an use-case where i need to reserve high volume memory buffer - (Video buffer) and it has to be shared between user-space and kernel space. Please help me how to we achieve this using "/dev/pmem" device ? When registering platform device - PMEM device, we are supplying base