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Date: Wed, 1 May 2013 17:59:58 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Julian Anastasov <ja@ssi.bg>, Simon Horman <horms@verge.net.au>,
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        linux-kernel@vger.kernel.org, Pablo Neira Ayuso <pablo@netfilter.org>,
        Dipankar Sarma <dipankar@in.ibm.com>
Subject: Re: [PATCH v2 1/2] sched: Add cond_resched_rcu_lock() helper
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On Wed, May 01, 2013 at 08:29:55AM -0700, Eric Dumazet wrote:
> On Wed, 2013-05-01 at 17:17 +0200, Peter Zijlstra wrote:
> > On Wed, May 01, 2013 at 05:46:37AM -0700, Paul E. McKenney wrote:
> > 
> > > If the only goal is to allow preemption, and if long grace periods are
> > > not a concern, then this alternate approach would work fine as well.
> > 
> > Hmm.. if that were the goal I'd like it to have a different name;
> > cond_resched*() has always been about preemption.
> 
> BTW, I do not remember why cond_resched() is not an empty macro
> when CONFIG_PREEMPT=y ?

Good question.. at at least, only the __might_sleep() construct. Ingo, happen
to remember why this is? Most of this infrastructure is from before my time.