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Date:   Fri, 19 Jul 2019 08:14:10 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Christoph Lameter <cl@linux.com>,
        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, Roman Gushchin <guro@fb.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shakeel Butt <shakeelb@google.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>
Subject: Re: [PATCH v2 2/2] mm, slab: Show last shrink time in us when
 slab/shrink is read
Message-ID: <20190719061410.GJ30461@dhcp22.suse.cz>
References: <20190717202413.13237-1-longman@redhat.com>
 <20190717202413.13237-3-longman@redhat.com>
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On Wed 17-07-19 16:24:13, Waiman Long wrote:
> The show method of /sys/kernel/slab/<slab>/shrink sysfs file currently
> returns nothing. This is now modified to show the time of the last
> cache shrink operation in us.

Isn't this something that tracing can be used for without any kernel
modifications?
-- 
Michal Hocko
SUSE Labs