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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="3B4EqaQuciegMUNCAnz5Lzg5cTwJnM1uT" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --3B4EqaQuciegMUNCAnz5Lzg5cTwJnM1uT Content-Type: multipart/mixed; boundary="dzGye9qwqLYQx04F4ajWCDwJOPGLZdKrs"; protected-headers="v1" From: Pavel Begunkov To: Ingo Molnar , Jens Axboe Cc: Ingo Molnar , Peter Zijlstra , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Message-ID: Subject: Re: [PATCH v2 0/2] Optimise io_uring completion waiting References: <20190923083549.GA42487@gmail.com> In-Reply-To: --dzGye9qwqLYQx04F4ajWCDwJOPGLZdKrs Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Sorry, mixed the threads. >> >> I'm not sure an extension is needed for such a special interface, why = not=20 >> just put a ->threshold value next to the ctx->wait field and use eithe= r=20 >> the regular wait_event() APIs with the proper condition, or=20 >> wait_event_cmd() style APIs if you absolutely need something more comp= lex=20 >> to happen inside? Ingo, io_uring works well without this patch just using wait_event_*() with proper condition, but there are performance issues with spurious wakeups. Detailed description in the previous mail. Am I missing something? Thanks >> >> Should result in a much lower linecount and no scheduler changes. :-) >> >> Thanks, >> >> Ingo >> >=20 --=20 Yours sincerely, Pavel Begunkov --dzGye9qwqLYQx04F4ajWCDwJOPGLZdKrs-- --3B4EqaQuciegMUNCAnz5Lzg5cTwJnM1uT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEE+6JuPTjTbx479o3OWt5b1Glr+6UFAl2I86IACgkQWt5b1Glr +6XqNxAAm4KZCQh3M7BMDBgN/Rnq89kWjICkQLKXqvhV/nPSu9bsY6fCB3tj1C/V s1tMQXuWEynbB6iewvBr/laIENP2hqiS27NdevYzjY12amktPxru6rpQs9GafCi7 N0Wip72JhCiaptGAmIdAair0HoWx6HQ+4WF5lMYFR2Zc8pyLIdkz+lk/xdHAs/+F T/viybKa9v4ZQ3T5VG/1grlCT9x71bHgOLdsMW6vAGEIdzNIMkwNr+6PxQAEAwWk sbjD0xezUN4e3W/RtXlhKL5hWUafciIZWavYlbM1f+llbk/TXRJPyw3qaKl7CZxA lfDARP566jkt5rfAA6aS4bkzpNz3zee5qdulOWsLYPLePSC5paqPJKvUpZuBhidU f7nx61lbsFAyI2XRN0rZDRsWaIGbtkFF0pzrFiWA8DEkrNTF2tM6MMguUcDNmRYV TQliaArdtycCET1QI0g3lQw3G0cZQhbbbpWbsLT3/NMDbPx6yLA6WAvP0DwQFdBi Jysi9akB/U9YrAXB/bAZyCMrKNpjYZWKIwMxU1s+1xhTTxcYyR6vtOlNhWr1ev0w CUd0DaNH57rzRY2v/07YmRafHcCDf7r1tCZ7DS6hmHp2wAP+dal2acjxfesxd6g5 eSkSJT/2pQVnc69xciG0eC1GVP6ZnSGwAYHnZT54rhw4O1r3hD0= =3vGs -----END PGP SIGNATURE----- --3B4EqaQuciegMUNCAnz5Lzg5cTwJnM1uT--