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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 24 Aug 2021 10:39:25 -0700
Message-ID: <CAHk-=wgrSmiwUfSGt1RPy5KJ_TLBTP5DB0-vT=PCxQY4C7uANA@mail.gmail.com>
Subject: Re: [pipe] 3b844826b6: stress-ng.sigio.ops_per_sec -99.3% regression
To:     kernel test robot <oliver.sang@intel.com>,
        Colin Ian King <colin.king@canonical.com>
Cc:     Sandeep Patil <sspatil@android.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org,
        kernel test robot <lkp@intel.com>,
        "Huang, Ying" <ying.huang@intel.com>,
        Feng Tang <feng.tang@intel.com>,
        Zhengjun Xing <zhengjun.xing@linux.intel.com>
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On Tue, Aug 24, 2021 at 10:32 AM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> We could do the same ugly thing for FASYNC that we do for EPOLLET -
> make it always fasync on new data, exactly because the previous SIGIO
> might not have emptied the buffer completely.

The patch would be something like the attached (UNTESTED!)

                  Linus

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