Date: Thu, 22 Oct 2009 06:45:38 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: "Leonidas ." <leonidas137@gmail.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: Can current macro be accessed from interrupt context?
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On Thu, 22 Oct 2009 04:10:49 -0700
"Leonidas ." <leonidas137@gmail.com> wrote:

> Hello,
> 
> Going through UTLK, it says that current macro makes sense only in
> case of process context,
> in case of interrupt context it is invalid.
> 
> But current would still be pointing to interrupted process right? The
> pointer would still be valid?
> Can I safely assume that whether or not interrupt handlers are
> executing on separate stacks or
> interrupted threads stack, current macro can be accessed from
> interrupt context?

not for interrupt threads, and that's where things are moving to.

for interrupt stacks you ought to be fine (current is just a pointer on
the stack, and last I looked we copied that pointer for each interrupt
to the irq stack)

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
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