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Date: Tue, 24 Jan 2006 07:53:19 -0700
From: Scott Long <scottl@samsco.org>
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To: Pranav Peshwe <pranavpeshwe@gmail.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Difference between a kthread and an ordinary process.
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Pranav Peshwe wrote:
> Hello,
>          When a kthread is created using the kthread_create (9)
> function, i found out that a new instance of struct proc is created
> and allocated for the thread just as in case of a creation of a new
> process.Also, the thread is assigned a pid as in the case of a
> process.
>   What is the difference between a kernel thread and a normal process
> created using fork ? except the address space sharing with swapper and
> kernel mode execution of the kthread. Is a kthread effectively just a
> process always running in kernel mode ?
> 

That is exactly what a kthread is.  There is some work in process to 
make them true threads within one or more processes.

Scott