From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 05/28] mm: allow PF_MEMALLOC from softirq context
Date: Sat, 23 Feb 2008 00:05:50 -0800
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	<20080220150305.905314000@chello.nl>
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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	netdev@vger.kernel.org, trond.myklebust@fys.uio.no
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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On Wed, 20 Feb 2008 15:46:15 +0100 Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> Allow PF_MEMALLOC to be set in softirq context. When running softirqs from
> a borrowed context save current->flags, ksoftirqd will have its own 
> task_struct.

The second sentence doesn't make sense.

> This is needed to allow network softirq packet processing to make use of
> PF_MEMALLOC.
>
> ...
>
> +#define tsk_restore_flags(p, pflags, mask) \
> +	do {	(p)->flags &= ~(mask); \
> +		(p)->flags |= ((pflags) & (mask)); } while (0)
> +

Does it need to be a macro?

If so, it really should cook up a temporary to avoid referencing p twice -
the children might be watching.