Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t

From	Kees Cook <keescook@chromium.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t
Date	2017-07-20 02:40 +0200
Message-ID	<u57Fw-7SI-5@gated-at.bofh.it> (permalink)
References	(3 earlier) <u55No-6BP-9@gated-at.bofh.it> <u566K-6L0-1@gated-at.bofh.it> <u566K-6L0-19@gated-at.bofh.it> <u56q6-77M-19@gated-at.bofh.it> <u56zL-7bx-3@gated-at.bofh.it>
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On Wed, Jul 19, 2017 at 4:20 PM, Kees Cook <keescook@chromium.org> wrote:
> On Wed, Jul 19, 2017 at 4:11 PM, Davidlohr Bueso <dave@stgolabs.net> wrote:
>> May I suggest using mmtests with the following config file:
>>
>> https://github.com/gormanm/mmtests/blob/7e070a810bc0af92e592e5121d0ea75fada51aeb/configs/config-global-dhp__workload-ipc-scale-short
>>
>> It will run two of Manfred's ipcscale sem benchmarks.
>
> I'll see if I can figure out how to use this for testing the fast
> refcount protection:
> https://lkml.org/lkml/2017/7/18/1223
>
> Then we could see:
>
> before conversion
> after conversion
> with CONFIG_REFCOUNT_FULL
> with fast refcount protection

I have no idea how to read this report. It seems to be mostly noise
(multiple baseline runs seem to show greater variability than compared
against the other possible results).

Test runs were atomic_t, atomic_t-2, refcount_t, refcount-full, and
refcount-fast. (Two baselines, refcount_t conversion, with FULL, and
with the fast implementation.) Output here:
http://pastebin.ubuntu.com/25129382/

-Kees

-- 
Kees Cook
Pixel Security

Thread

Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to  refcount_t Andrew Morton <akpm@linux-foundation.org> - 2017-07-20 00:40 +0200
  Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to  refcount_t Davidlohr Bueso <dave@stgolabs.net> - 2017-07-20 01:00 +0200
    Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to  refcount_t Andrew Morton <akpm@linux-foundation.org> - 2017-07-20 01:00 +0200
      Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to  refcount_t Davidlohr Bueso <dave@stgolabs.net> - 2017-07-20 01:20 +0200
        Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t Kees Cook <keescook@chromium.org> - 2017-07-20 01:30 +0200
          Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t Kees Cook <keescook@chromium.org> - 2017-07-20 02:40 +0200
      Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to  refcount_t Ingo Molnar <mingo@kernel.org> - 2017-07-20 11:40 +0200
        Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t ebiederm@xmission.com (Eric W. Biederman) - 2017-07-20 14:50 +0200
          Re: [PATCH 1/3] ipc: convert ipc_namespace.count from atomic_t to refcount_t Kees Cook <keescook@chromium.org> - 2017-07-20 17:20 +0200

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