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Date: Tue, 26 Jul 2016 20:57:12 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@kernel.org>
Cc: Dave Anderson <anderson@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Wang Shu <shuwang@redhat.com>, linux-kernel@vger.kernel.org,
        Tejun Heo <tj@kernel.org>, Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH 0/1] (Was: introduce
 for_each_process_thread_{break,continue}() helpers)
Message-ID: <20160726185712.GA4088@redhat.com>
References: <20160725162332.GA23935@redhat.com>
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On 07/25, Oleg Nesterov wrote:
>
> IMHO this makes sense in any case, but mostly this is preparation for
> another change: show_state_filter() should be preemptible. But this needs
> more discussion, I'll write another email/patch when I fully understand
> the hard-lockup caused by sysrq-t.

Yes, we need to do something with show_state_filter() anyway, I think.

OTOH, I believe this simple change in multi_cpu_stop() makes sense too
regardless.

Oleg.