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Date:   Wed, 7 Mar 2018 09:58:33 -0800
From:   "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Lai Jiangshan <jiangshanlai+lkml@gmail.com>,
        Tejun Heo <tj@kernel.org>, torvalds@linux-foundation.org,
        jannh@google.com, bcrl@kvack.org, viro@zeniv.linux.org.uk,
        kent.overstreet@gmail.com, security@kernel.org,
        LKML <linux-kernel@vger.kernel.org>, kernel-team@fb.com
Subject: Re: [PATCH 7/7] RCU, workqueue: Implement rcu_work
Reply-To: paulmck@linux.vnet.ibm.com
References: <20180306172657.3060270-1-tj@kernel.org>
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On Wed, Mar 07, 2018 at 05:23:17PM +0100, Peter Zijlstra wrote:
> On Wed, Mar 07, 2018 at 06:54:08AM -0800, Paul E. McKenney wrote:
> > One downside of allowing RCU callback functions to sleep is that
> > one poorly written callback can block a bunch of other ones.
> 
> Not to mention that we really want the RCU callbacks to be simple and
> short. Needing fancy things in the callback really should be the
> exception not the rule.

Very much agreed with that as well!

Besides, Tejun's queue_rcu_work() provides this functionality and
seems pretty straightforward to use.

							Thanx, Paul