RE: spinlock on uniprocessor systems

["Mukund JB." <mukundjb@xxxxxxxxxxxxxxxxxxxxx>]

Dear Fawad,

> AFAIK in kernel without preemption and no SMP the process (kernel
> process) will never be rescheduled until unless it voluntarily call
> schedule or releases CPU. You can see this behaviour by just inserting
> while(1); (infinite loop) with-in your module and your system will
> hang !  (CMIIW)
 
I have tried this earlier version of 2.4 kernels and found what you
mentioned. I found the same on 2.6.x kernel with Preemption & SMP
disabled.

But, when I tried this on a 2.6.x kernel with Preemption & SMP enabled I
fond that the kernel hangs with some messages.

I tried this by inserting a "while (1);" in close call. When APP calls
close () call I found the kernel hangs for a while & immediately results
in a crash.
What is the reason for this? Is it the timer interrupt (ISR)that causes
this? 

Regards,
Mukund Jampala

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