From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: disable preemption before call smp_processor_id()
Date: Sat, 07 Aug 2010 20:37:00 -0700 (PDT)
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From: Changli Gao <xiaosuo@gmail.com>
Date: Sat,  7 Aug 2010 17:26:02 +0800

> Although netif_rx() isn't expected to be called in process context with
> preemption enabled, it'd better handle this case. And this is why get_cpu()
> is used in the non-RPS #ifdef branch. If tree RCU is selected,
> rcu_read_lock() won't disable preemption, so preempt_disable() should be
> called explictly.
> 
> Signed-off-by: Changli Gao <xiaosuo@gmail.com>

Applied, thanks Changli.

Paul, perhaps the comment above rcu_read_lock()'s definition should
be updated in rcupdate.h?  It says blocking is not allowed inside
of a read side critical section, but obviously with tree-rcu that
is not the case.

Either we should add a mention of tree-rcu's semantics or just remote
this part of the comment altogether.