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Message-ID: <50EAC722.9050203@mellanox.com>
Date: Mon, 7 Jan 2013 15:01:22 +0200
From: Amir Vadai <amirv@mellanox.com>
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To: David Decotigny <decot@googlers.com>
CC: <linux-kernel@vger.kernel.org>, Ben Hutchings <bhutchings@solarflare.com>,
        "David S. Miller" <davem@davemloft.net>,
        Or Gerlitz <ogerlitz@mellanox.com>,
        "Paul E. McKenney" <paul.mckenney@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Josh Triplett" <josh@joshtriplett.org>,
        David Howells <dhowells@redhat.com>,
        "Paul Gortmaker" <paul.gortmaker@windriver.com>
Subject: Re: [PATCH v4] lib: cpu_rmap: avoid flushing all workqueues
References: <cover.1357163124.git.decot@googlers.com> <bb2493cb7d0b36f35282d77c1f07727601f9c751.1357163124.git.decot@googlers.com>
In-Reply-To: <bb2493cb7d0b36f35282d77c1f07727601f9c751.1357163124.git.decot@googlers.com>
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On 02/01/2013 23:52, 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@googlers.com>
> ---
>   include/linux/cpu_rmap.h  |   13 +++-------
>   include/linux/interrupt.h |    5 ----
>   lib/cpu_rmap.c            |   63 +++++++++++++++++++++++++++++++++++++++++----
>   3 files changed, 62 insertions(+), 19 deletions(-)
>

Acked-by: Amir Vadai <amirv@mellanox.com>