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Re: suspenind a process

Helo...

> How does process get suspended
>
> 1. When running in user mode
> 2. When running in kernel mode

Well, IMHO suspended might be interpreted as task in TASK_STOPPED, 
TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE. All these task state 
modification is done on kernel mode in response of certain signal, 
sleep(), waiting for disk read and any other kind of  operation that 
implicitly call set_task_state in kernel space.

One case that I am not sure whether suspension is done on kernel space 
or user space, is when you are doing instruction trace using gdb (in 
other word, setting TF--Trap Flag). All I know, when TF is set, 
exception is triggered and in turn it calls exception handler. 
Exception handler work in kernel space....so personally I say this is 
also happen on kernel space. But I allow other people to CMIIW

regards

Mulyadi


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