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Tue, 11 Feb 2020 12:58:04 -0800 (PST) Received: from [192.168.43.18] ([109.126.145.62]) by smtp.gmail.com with ESMTPSA id f127sm5313446wma.4.2020.02.11.12.58.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Feb 2020 12:58:03 -0800 (PST) To: Jens Axboe , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: <728f583e7835cf0c74b8dc8fbeddb58970f477a5.1581450491.git.asml.silence@gmail.com> <4a08cc5a-2100-3a31-becb-c16592905c86@kernel.dk> From: Pavel Begunkov Autocrypt: addr=asml.silence@gmail.com; prefer-encrypt=mutual; keydata= mQINBFmKBOQBEAC76ZFxLAKpDw0bKQ8CEiYJRGn8MHTUhURL02/7n1t0HkKQx2K1fCXClbps bdwSHrhOWdW61pmfMbDYbTj6ZvGRvhoLWfGkzujB2wjNcbNTXIoOzJEGISHaPf6E2IQx1ik9 6uqVkK1OMb7qRvKH0i7HYP4WJzYbEWVyLiAxUj611mC9tgd73oqZ2pLYzGTqF2j6a/obaqha +hXuWTvpDQXqcOZJXIW43atprH03G1tQs7VwR21Q1eq6Yvy2ESLdc38EqCszBfQRMmKy+cfp W3U9Mb1w0L680pXrONcnlDBCN7/sghGeMHjGKfNANjPc+0hzz3rApPxpoE7HC1uRiwC4et83 CKnncH1l7zgeBT9Oa3qEiBlaa1ZCBqrA4dY+z5fWJYjMpwI1SNp37RtF8fKXbKQg+JuUjAa9 Y6oXeyEvDHMyJYMcinl6xCqCBAXPHnHmawkMMgjr3BBRzODmMr+CPVvnYe7BFYfoajzqzq+h EyXSl3aBf0IDPTqSUrhbmjj5OEOYgRW5p+mdYtY1cXeK8copmd+fd/eTkghok5li58AojCba jRjp7zVOLOjDlpxxiKhuFmpV4yWNh5JJaTbwCRSd04sCcDNlJj+TehTr+o1QiORzc2t+N5iJ NbILft19Izdn8U39T5oWiynqa1qCLgbuFtnYx1HlUq/HvAm+kwARAQABtDFQYXZlbCBCZWd1 bmtvdiAoc2lsZW5jZSkgPGFzbWwuc2lsZW5jZUBnbWFpbC5jb20+iQJOBBMBCAA4FiEE+6Ju PTjTbx479o3OWt5b1Glr+6UFAlmKBOQCGwMFCwkIBwIGFQgJCgsCBBYCAwECHgECF4AACgkQ Wt5b1Glr+6WxZA//QueaKHzgdnOikJ7NA/Vq8FmhRlwgtP0+E+w93kL+ZGLzS/cUCIjn2f4Q Mcutj2Neg0CcYPX3b2nJiKr5Vn0rjJ/suiaOa1h1KzyNTOmxnsqE5fmxOf6C6x+NKE18I5Jy xzLQoktbdDVA7JfB1itt6iWSNoOTVcvFyvfe5ggy6FSCcP+m1RlR58XxVLH+qlAvxxOeEr/e aQfUzrs7gqdSd9zQGEZo0jtuBiB7k98t9y0oC9Jz0PJdvaj1NZUgtXG9pEtww3LdeXP/TkFl HBSxVflzeoFaj4UAuy8+uve7ya/ECNCc8kk0VYaEjoVrzJcYdKP583iRhOLlZA6HEmn/+Gh9 4orG67HNiJlbFiW3whxGizWsrtFNLsSP1YrEReYk9j1SoUHHzsu+ZtNfKuHIhK0sU07G1OPN 2rDLlzUWR9Jc22INAkhVHOogOcc5ajMGhgWcBJMLCoi219HlX69LIDu3Y34uIg9QPZIC2jwr 24W0kxmK6avJr7+n4o8m6sOJvhlumSp5TSNhRiKvAHB1I2JB8Q1yZCIPzx+w1ALxuoWiCdwV M/azguU42R17IuBzK0S3hPjXpEi2sK/k4pEPnHVUv9Cu09HCNnd6BRfFGjo8M9kZvw360gC1 reeMdqGjwQ68o9x0R7NBRrtUOh48TDLXCANAg97wjPoy37dQE7e5Ag0EWYoE5AEQAMWS+aBV IJtCjwtfCOV98NamFpDEjBMrCAfLm7wZlmXy5I6o7nzzCxEw06P2rhzp1hIqkaab1kHySU7g dkpjmQ7Jjlrf6KdMP87mC/Hx4+zgVCkTQCKkIxNE76Ff3O9uTvkWCspSh9J0qPYyCaVta2D1 Sq5HZ8WFcap71iVO1f2/FEHKJNz/YTSOS/W7dxJdXl2eoj3gYX2UZNfoaVv8OXKaWslZlgqN jSg9wsTv1K73AnQKt4fFhscN9YFxhtgD/SQuOldE5Ws4UlJoaFX/yCoJL3ky2kC0WFngzwRF Yo6u/KON/o28yyP+alYRMBrN0Dm60FuVSIFafSqXoJTIjSZ6olbEoT0u17Rag8BxnxryMrgR dkccq272MaSS0eOC9K2rtvxzddohRFPcy/8bkX+t2iukTDz75KSTKO+chce62Xxdg62dpkZX xK+HeDCZ7gRNZvAbDETr6XI63hPKi891GeZqvqQVYR8e+V2725w+H1iv3THiB1tx4L2bXZDI DtMKQ5D2RvCHNdPNcZeldEoJwKoA60yg6tuUquvsLvfCwtrmVI2rL2djYxRfGNmFMrUDN1Xq F3xozA91q3iZd9OYi9G+M/OA01husBdcIzj1hu0aL+MGg4Gqk6XwjoSxVd4YT41kTU7Kk+/I 5/Nf+i88ULt6HanBYcY/+Daeo/XFABEBAAGJAjYEGAEIACAWIQT7om49ONNvHjv2jc5a3lvU aWv7pQUCWYoE5AIbDAAKCRBa3lvUaWv7pfmcEACKTRQ28b1y5ztKuLdLr79+T+LwZKHjX++P 4wKjEOECCcB6KCv3hP+J2GCXDOPZvdg/ZYZafqP68Yy8AZqkfa4qPYHmIdpODtRzZSL48kM8 LRzV8Rl7J3ItvzdBRxf4T/Zseu5U6ELiQdCUkPGsJcPIJkgPjO2ROG/ZtYa9DvnShNWPlp+R uPwPccEQPWO/NP4fJl2zwC6byjljZhW5kxYswGMLBwb5cDUZAisIukyAa8Xshdan6C2RZcNs rB3L7vsg/R8UCehxOH0C+NypG2GqjVejNZsc7bgV49EOVltS+GmGyY+moIzxsuLmT93rqyII 5rSbbcTLe6KBYcs24XEoo49Zm9oDA3jYvNpeYD8rDcnNbuZh9kTgBwFN41JHOPv0W2FEEWqe JsCwQdcOQ56rtezdCJUYmRAt3BsfjN3Jn3N6rpodi4Dkdli8HylM5iq4ooeb5VkQ7UZxbCWt UVMKkOCdFhutRmYp0mbv2e87IK4erwNHQRkHUkzbsuym8RVpAZbLzLPIYK/J3RTErL6Z99N2 m3J6pjwSJY/zNwuFPs9zGEnRO4g0BUbwGdbuvDzaq6/3OJLKohr5eLXNU3JkT+3HezydWm3W OPhauth7W0db74Qd49HXK0xe/aPrK+Cp+kU1HRactyNtF8jZQbhMCC8vMGukZtWaAwpjWiiH bA== Subject: Re: [PATCH 3/5] io_uring: fix reassigning work.task_pid from io-wq Message-ID: Date: Tue, 11 Feb 2020 23:57:13 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <4a08cc5a-2100-3a31-becb-c16592905c86@kernel.dk> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="r3ufS8hWOO0jlZFGhNNoJ76CAUirJEWUa" Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --r3ufS8hWOO0jlZFGhNNoJ76CAUirJEWUa Content-Type: multipart/mixed; boundary="nrWwE987J8OkG3OdY3y7K4XXiCHWftVzZ"; protected-headers="v1" From: Pavel Begunkov To: Jens Axboe , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Message-ID: Subject: Re: [PATCH 3/5] io_uring: fix reassigning work.task_pid from io-wq References: <728f583e7835cf0c74b8dc8fbeddb58970f477a5.1581450491.git.asml.silence@gmail.com> <4a08cc5a-2100-3a31-becb-c16592905c86@kernel.dk> In-Reply-To: <4a08cc5a-2100-3a31-becb-c16592905c86@kernel.dk> --nrWwE987J8OkG3OdY3y7K4XXiCHWftVzZ Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 11/02/2020 23:21, Jens Axboe wrote: > On 2/11/20 1:01 PM, Pavel Begunkov wrote: >> If a request got into io-wq context, io_prep_async_work() has already >> been called. Most of the stuff there is idempotent with an exception >> that it'll set work.task_pid to task_pid_vnr() of an io_wq worker thre= ad >> >> Do only what's needed, that's io_prep_linked_timeout() and setting >> IO_WQ_WORK_UNBOUND. >=20 > Rest of the series aside, I'm going to fix-up the pid addition to > only set if it's zero like the others. IMO, io_req_work_grab_env() should never be called from io-wq. It'd do no= thing good but open space for subtle bugs. And if that's enforced (as done in t= his patch), it's safe to set @pid multiple times. Probably, it worth to add the check just to not go through task_pid_vnr()= several times. --=20 Pavel Begunkov --nrWwE987J8OkG3OdY3y7K4XXiCHWftVzZ-- --r3ufS8hWOO0jlZFGhNNoJ76CAUirJEWUa Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEE+6JuPTjTbx479o3OWt5b1Glr+6UFAl5DFTQACgkQWt5b1Glr +6U4HBAAiVXVbwa8UiXiDXRRjHe/Uwk9VmBUYqKOjRAm0LCbMxrrVvA5WNj/heOA Lw3aEiKKzGVYyhRpxyV8HPfMfb41psM7XWs0DEPMFgNR89H50nCLkkfeqfjx2UKL 9F0AkfxXvFwoGLsgRq4SGN8xAjq0RifAeQjZqlXjIYXY3ChA+nYda2TxUAUrUfoM ubNOAjr+xtOLV7DjyoDzc6jU7lYro9ndKn2VnBLAXWHAdNbLbRU0uzgruZHJ7JOS SkKR/easNwKco+KXU+rLFA1P7TdYobJokH8tS4t3sGJCvqNTSfrWNmIhgi/Jl4SF l7ktcd6EIowyf2NPd5ZRKcHlRvK3gj5mKr/Pa8eHoAZzL2p8OgM/SmDIMPaU1VTj JX38BymP2FhfMcBzW9gutitqSa3o5ZsFyBoQhmxLScZtZ4PKpejne4a47siY5KyO 0xjAAK4OlRznOarq1pjCYFHiaJn26SyMi2ooAQsgGvztgUPbrludXTSg6iFpecZ1 X+tL8q20zEPt6XNyDEdKIgPJtOQFZM+a7X2rf70U43rXdyST4IMcqfdAq1USjb14 hd//fpnrnA6iS/0ASGdT/d0w8ZRJ7Q+MIl2xklBL4fmZciQI+oF1E7kzt3fn/4pi EhIAbJwaT+D9M58R2+ZSwuZj1TIqttHn7Uy36bh423Kgyx7cw3s= =jU+T -----END PGP SIGNATURE----- --r3ufS8hWOO0jlZFGhNNoJ76CAUirJEWUa--