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Date:	Sat, 29 Dec 2012 12:36:44 -0800
From:	Josh Triplett <josh@...htriplett.org>
To:	David Decotigny <decot@...glers.com>
Cc:	linux-kernel@...r.kernel.org,
	Ben Hutchings <bhutchings@...arflare.com>,
	"David S. Miller" <davem@...emloft.net>,
	Or Gerlitz <ogerlitz@...lanox.com>,
	Amir Vadai <amirv@...lanox.com>,
	"Paul E. McKenney" <paul.mckenney@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Howells <dhowells@...hat.com>,
	Paul Gortmaker <paul.gortmaker@...driver.com>
Subject: Re: [PATCH v3] lib: cpu_rmap: avoid flushing all workqueues

On Sat, Dec 29, 2012 at 11:57:09AM -0800, David Decotigny wrote:
> In some cases, free_irq_cpu_rmap() is called while holding a lock
> (eg. rtnl). This can lead to deadlocks, because it invokes
> flush_scheduled_work() which ends up waiting for whole system
> workqueue to flush, but some pending works might try to acquire the
> lock we are already holding.
> 
> This commit uses reference-counting to replace
> irq_run_affinity_notifiers(). It also removes
> irq_run_affinity_notifiers() altogether.
> 
> Signed-off-by: David Decotigny <decot@...glers.com>

You might consider adding a cpu_rmap_get to parallel cpu_rmap_put.

Also, why keep free_cpu_rmap around at this point?  As far as I can
tell, it has no callers.

Otherwise, this looks good to me.

- Josh Triplett
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