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From: Christoph Lameter <cl@linux.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Michal Hocko <mhocko@kernel.org>,
	Mel Gorman <mgorman@techsingularity.net>,
	Vlastimil Babka <vbabka@suse.cz>,
	Dmitry Vyukov <dvyukov@google.com>, Tejun Heo <tj@kernel.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	syzkaller <syzkaller@googlegroups.com>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: mm: deadlock between get_online_cpus/pcpu_alloc
Date: Wed, 8 Feb 2017 09:06:47 -0600 (CST)	[thread overview]
Message-ID: <alpine.DEB.2.20.1702080906100.3955@east.gentwo.org> (raw)
In-Reply-To: <alpine.DEB.2.20.1702072319200.8117@nanos>

On Tue, 7 Feb 2017, Thomas Gleixner wrote:

> > Yep. Hotplug events are pretty significant. Using stop_machine_XXXX() etc
> > would be advisable and that would avoid the taking of locks and get rid of all the
> > ocmplexity, reduce the code size and make the overall system much more
> > reliable.
>
> Huch? stop_machine() is horrible and heavy weight. Don't go there, there
> must be simpler solutions than that.

Inserting or removing hardware is a heavy process. This would help quite a
bit with these issues for loops over active cpus.

  parent reply	other threads:[~2017-02-08 15:08 UTC|newest]

Thread overview: 60+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-29 12:44 mm: deadlock between get_online_cpus/pcpu_alloc Dmitry Vyukov
2017-01-29 17:22 ` Vlastimil Babka
2017-01-30 15:48   ` Dmitry Vyukov
2017-02-06 19:13     ` Dmitry Vyukov
2017-02-06 22:05       ` Mel Gorman
2017-02-07  8:48         ` Michal Hocko
2017-02-07  9:23           ` Vlastimil Babka
2017-02-07  9:46             ` Mel Gorman
2017-02-07  9:53             ` Michal Hocko
2017-02-07 10:42             ` Mel Gorman
2017-02-07 11:13               ` Mel Gorman
2017-02-07  9:43           ` Mel Gorman
2017-02-07  9:49             ` Vlastimil Babka
2017-02-07 10:05               ` Michal Hocko
2017-02-07 10:28               ` Mel Gorman
2017-02-07 10:35                 ` Michal Hocko
2017-02-07 11:34                   ` Mel Gorman
2017-02-07 11:43                     ` Michal Hocko
2017-02-07 11:54                       ` Vlastimil Babka
2017-02-07 12:08                         ` Michal Hocko
2017-02-07 12:37                       ` Michal Hocko
2017-02-07 12:43                         ` Vlastimil Babka
2017-02-07 12:48                           ` Michal Hocko
2017-02-07 13:57                             ` Vlastimil Babka
2017-02-07 13:58                         ` Mel Gorman
2017-02-07 14:19                           ` Michal Hocko
2017-02-07 15:34                             ` Michal Hocko
2017-02-07 16:22                               ` Mel Gorman
2017-02-07 16:41                                 ` Michal Hocko
2017-02-07 16:55                                   ` Christoph Lameter
2017-02-07 22:25                                     ` Thomas Gleixner
2017-02-08  7:35                                       ` Michal Hocko
2017-02-08 12:02                                         ` Thomas Gleixner
2017-02-08 12:21                                           ` Michal Hocko
2017-02-08 12:26                                           ` Mel Gorman
2017-02-08 13:23                                             ` Thomas Gleixner
2017-02-08 14:03                                               ` Mel Gorman
2017-02-08 14:11                                                 ` Peter Zijlstra
2017-02-08 15:11                                         ` Christoph Lameter
2017-02-08 15:21                                           ` Michal Hocko
2017-02-08 16:17                                             ` Christoph Lameter
2017-02-08 17:46                                               ` Thomas Gleixner
2017-02-09  3:15                                                 ` Christoph Lameter
2017-02-09 11:42                                                   ` Thomas Gleixner
2017-02-09 14:00                                                     ` Christoph Lameter
2017-02-09 14:53                                                       ` Thomas Gleixner
2017-02-09 15:42                                                         ` Christoph Lameter
2017-02-09 16:12                                                           ` Thomas Gleixner
2017-02-09 17:22                                                             ` Christoph Lameter
2017-02-09 17:40                                                               ` Thomas Gleixner
2017-02-09 19:15                                                               ` Michal Hocko
2017-02-10 17:58                                                                 ` Christoph Lameter
2017-02-08 15:06                                       ` Christoph Lameter [this message]
2017-02-07 17:03                               ` Tejun Heo
2017-02-07 20:16                                 ` Michal Hocko
2017-02-07 13:03                       ` Mel Gorman
2017-02-07 13:48                         ` Michal Hocko
2017-02-07 11:24         ` Tetsuo Handa
2017-02-07  8:43       ` Michal Hocko
2017-02-07 21:53       ` Thomas Gleixner

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