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Date: Fri, 4 Oct 2013 21:42:51 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>, Oleg Nesterov <oleg@redhat.com>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/5] rcusync: introduce struct rcu_sync_ops
Message-ID: <20131004194251.GX15690@laptop.programming.kicks-ass.net>
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On Fri, Oct 04, 2013 at 12:38:37PM -0700, Linus Torvalds wrote:
> On Fri, Oct 4, 2013 at 12:30 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > As all the rcu_synchronization() methods (on non UP) are quite
> > expensive, I doubt that this optimization is worth anything.
> 
> Maybe. It just annoys me, because afaik, the function that gets called
> is always static per callsite.

Yes, very much so indeed. Worst is that we have no users of the regular
RCU and RCU_BH variants and only included them for completeness since
the general operation is just as valid for those.