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Date: Tue, 10 Apr 2018 13:23:53 -0700
From: Tejun Heo <tj@kernel.org>
Subject: Re: [RFC] mm, slab: reschedule cache_reap() on the same CPU
Message-ID: <20180410202353.GB793541@devbig577.frc2.facebook.com>
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To: Vlastimil Babka <vbabka@suse.cz>
Cc: Christopher Lameter <cl@linux.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim <iamjoonsoo.kim@lge.com>, David Rientjes <rientjes@google.com>, Pekka Enberg <penberg@kernel.org>, Lai Jiangshan <jiangshanlai@gmail.com>, John Stultz <john.stultz@linaro.org>, Thomas Gleixner <tglx@linutronix.de>, Stephen Boyd <sboyd@kernel.org>

Hello,

On Tue, Apr 10, 2018 at 10:13:33PM +0200, Vlastimil Babka wrote:
> > For percpu work items, they'll keep executing on the same cpu it
> > started on unless the cpu goes down while executing.
> 
> Right, but before this patch, with just schedule_delayed_work() i.e.
> non-percpu? If such work can migrate in the middle, the slab bug is
> potentially much more serious.

That's still per-cpu.  The only time the local binding breaks is when
the kernel is explicitly told to do so through explicit unbound_mask
or force_rr debug option.

Thanks.

-- 
tejun