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Subject: Re: [PATCH v2 2/2] mm, slab: Show last shrink time in us when
 slab/shrink is read
From:   Waiman Long <longman@redhat.com>
To:     Christopher Lameter <cl@linux.com>
Cc:     Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <guro@fb.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shakeel Butt <shakeelb@google.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>
References: <20190717202413.13237-1-longman@redhat.com>
 <20190717202413.13237-3-longman@redhat.com>
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 <6fb9f679-02d1-c33f-2d79-4c2eaa45d264@redhat.com>
Organization: Red Hat
Message-ID: <9d35da26-6d85-d879-c966-3577bdb0cf02@redhat.com>
Date:   Thu, 18 Jul 2019 14:04:33 -0400
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On 7/18/19 10:36 AM, Waiman Long wrote:
>>> CONFIG_SLUB_DEBUG depends on CONFIG_SYSFS. So the new shrink_us field
>>> is always available to the shrink methods.
>> Aside from minimal systems without CONFIG_SYSFS... Does this build without
>> CONFIG_SYSFS?
> The sysfs code in mm/slub.c is guarded by CONFIG_SLUB_DEBUG which, in
> turn, depends on CONFIG_SYSFS. So if CONFIG_SYSFS is off, the shrink
> sysfs methods will be off as well. I haven't tried doing a minimal
> build. I will certainly try that, but I don't expect any problem here.

I have tried a tiny config with slub. There was no compilation problem.

-Longman