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From:   Max Kellermann <max.kellermann@ionos.com>
Date:   Wed, 18 Oct 2023 10:12:21 +0200
Message-ID: <CAKPOu+9bZtu80NncqLET_ycZcWynZFHuWGRC4HU2Od9NrsjnCw@mail.gmail.com>
Subject: Re: [linux-next:master] [drivers/char/mem] 1b057bd800:
 stress-ng.splice.ops_per_sec -99.8% regression
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Oliver Sang <oliver.sang@intel.com>, oe-lkp@lists.linux.dev,
        lkp@intel.com, Linux Memory Management List <linux-mm@kvack.org>,
        linux-kernel@vger.kernel.org, ying.huang@intel.com,
        feng.tang@intel.com, fengwei.yin@intel.com
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On Wed, Oct 18, 2023 at 9:57=E2=80=AFAM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
> That's odd given that as was pointed out, this test does not even touch
> the code paths that this patch changed.

I think I mixed up the "vmsplice" and the "splice" tests, and my
conclusion was wrong, sorry.
This performance regression is about the "splice" test which indeed
uses /dev/zero. I'll have a closer look and get back to you.