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Date:   Tue, 23 Oct 2018 09:23:06 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Uladzislau Rezki <urezki@gmail.com>, Shuah Khan <shuah@kernel.org>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Garnier <thgarnie@google.com>,
        Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Joel Fernandes <joelaf@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@elte.hu>, Tejun Heo <tj@kernel.org>
Subject: Re: [RFC PATCH 0/2] improve vmalloc allocation
Message-ID: <20181023072306.GN18839@dhcp22.suse.cz>
References: <20181019173538.590-1-urezki@gmail.com>
 <20181022125142.GD18839@dhcp22.suse.cz>
 <20181022165253.uphv3xzqivh44o3d@pc636>
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Hi Shuah,

On Mon 22-10-18 18:52:53, Uladzislau Rezki wrote:
> On Mon, Oct 22, 2018 at 02:51:42PM +0200, Michal Hocko wrote:
> > Hi,
> > I haven't read through the implementation yet but I have say that I
> > really love this cover letter. It is clear on intetion, it covers design
> > from high level enough to start discussion and provides a very nice
> > testing coverage. Nice work!
> > 
> > I also think that we need a better performing vmalloc implementation
> > long term because of the increasing number of kvmalloc users.
> > 
> > I just have two mostly workflow specific comments.
> > 
> > > A test-suite patch you can find here, it is based on 4.18 kernel.
> > > ftp://vps418301.ovh.net/incoming/0001-mm-vmalloc-stress-test-suite-v4.18.patch
> > 
> > Can you fit this stress test into the standard self test machinery?
> > 
> If you mean "tools/testing/selftests", then i can fit that as a kernel module.
> But not all the tests i can trigger from kernel module, because 3 of 8 tests
> use __vmalloc_node_range() function that is not marked as EXPORT_SYMBOL.

Is there any way to conditionally export these internal symbols just for
kselftests? Or is there any other standard way how to test internal
functionality that is not exported to modules?
-- 
Michal Hocko
SUSE Labs