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Re: task_struct.active_mm





On Wed, 2 Jul 2003, Ed L Cashin wrote:

> Hi.  I'm trying to clarify my understanding of the role of the
> active_mm field in the task_struct.
>
> Is it true that kernel threads and interrupt handlers use the
> active_mm field to borrow the mm of a process?
>
> Is it true that in a process, which always has a non-null mm, always
> has current->mm == current->active_mm?

  Yes you are correct. the kernel threads use the active vm of the process
that ran last. This is done to decrease the process switch time with the
help of . As the
kernel threads do not use user space, it is safe to borrow the mm of
another process.

HTH,
Raghu.
>
> --
> --Ed L Cashin            |   PGP public key:
>   ecashin@uga.edu        |   http://noserose.net/e/pgp/
>
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