From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48AECC2BA19 for ; Tue, 14 Apr 2020 07:54:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26142206D5 for ; Tue, 14 Apr 2020 07:54:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="G/l1ZTWH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406917AbgDNHyz (ORCPT ); Tue, 14 Apr 2020 03:54:55 -0400 Received: from mout.web.de ([212.227.17.12]:45421 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406887AbgDNHyx (ORCPT ); Tue, 14 Apr 2020 03:54:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1586850852; bh=hAQpUX7TTke6jwz7Bl++PDHIsePwoXNRIF38VkwFUaE=; h=X-UI-Sender-Class:To:Cc:Subject:From:Date; b=G/l1ZTWHKwuNuZWZbghnLQ/23KaJGCwclKP+NnkQQjQe5QH/NmXNAwqQ+YZdq3WRN wBELouEXa1jiJ9q4RRClC8rdqjWbXtTTeJnsBV7L9amDZq4iiUGeVKojbcDR5U7cHu TKL9uuvSMvQZ0moa2IYGO5HlAO1qe8VSF/qvpTMM= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.3] ([78.49.66.171]) by smtp.web.de (mrweb103 [213.165.67.124]) with ESMTPSA (Nemesis) id 0LtnvF-1jE7Yf1UhB-0117Rc; Tue, 14 Apr 2020 09:54:12 +0200 To: Xiao Yang , linux-kselftest@vger.kernel.org, linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Steven Rostedt , Xiao Yang Subject: Re: [PATCH v2] tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation From: Markus Elfring Autocrypt: addr=Markus.Elfring@web.de; prefer-encrypt=mutual; keydata= mQINBFg2+xABEADBJW2hoUoFXVFWTeKbqqif8VjszdMkriilx90WB5c0ddWQX14h6w5bT/A8 +v43YoGpDNyhgA0w9CEhuwfZrE91GocMtjLO67TAc2i2nxMc/FJRDI0OemO4VJ9RwID6ltwt mpVJgXGKkNJ1ey+QOXouzlErVvE2fRh+KXXN1Q7fSmTJlAW9XJYHS3BDHb0uRpymRSX3O+E2 lA87C7R8qAigPDZi6Z7UmwIA83ZMKXQ5stA0lhPyYgQcM7fh7V4ZYhnR0I5/qkUoxKpqaYLp YHBczVP+Zx/zHOM0KQphOMbU7X3c1pmMruoe6ti9uZzqZSLsF+NKXFEPBS665tQr66HJvZvY GMDlntZFAZ6xQvCC1r3MGoxEC1tuEa24vPCC9RZ9wk2sY5Csbva0WwYv3WKRZZBv8eIhGMxs rcpeGShRFyZ/0BYO53wZAPV1pEhGLLxd8eLN/nEWjJE0ejakPC1H/mt5F+yQBJAzz9JzbToU 5jKLu0SugNI18MspJut8AiA1M44CIWrNHXvWsQ+nnBKHDHHYZu7MoXlOmB32ndsfPthR3GSv jN7YD4Ad724H8fhRijmC1+RpuSce7w2JLj5cYj4MlccmNb8YUxsE8brY2WkXQYS8Ivse39MX BE66MQN0r5DQ6oqgoJ4gHIVBUv/ZwgcmUNS5gQkNCFA0dWXznQARAQABtCZNYXJrdXMgRWxm cmluZyA8TWFya3VzLkVsZnJpbmdAd2ViLmRlPokCVAQTAQgAPhYhBHDP0hzibeXjwQ/ITuU9 Figxg9azBQJYNvsQAhsjBQkJZgGABQsJCAcCBhUICQoLAgQWAgMBAh4BAheAAAoJEOU9Figx g9azcyMP/iVihZkZ4VyH3/wlV3nRiXvSreqg+pGPI3c8J6DjP9zvz7QHN35zWM++1yNek7Ar OVXwuKBo18ASlYzZPTFJZwQQdkZSV+atwIzG3US50ZZ4p7VyUuDuQQVVqFlaf6qZOkwHSnk+ CeGxlDz1POSHY17VbJG2CzPuqMfgBtqIU1dODFLpFq4oIAwEOG6fxRa59qbsTLXxyw+PzRaR LIjVOit28raM83Efk07JKow8URb4u1n7k9RGAcnsM5/WMLRbDYjWTx0lJ2WO9zYwPgRykhn2 sOyJVXk9xVESGTwEPbTtfHM+4x0n0gC6GzfTMvwvZ9G6xoM0S4/+lgbaaa9t5tT/PrsvJiob kfqDrPbmSwr2G5mHnSM9M7B+w8odjmQFOwAjfcxoVIHxC4Cl/GAAKsX3KNKTspCHR0Yag78w i8duH/eEd4tB8twcqCi3aCgWoIrhjNS0myusmuA89kAWFFW5z26qNCOefovCx8drdMXQfMYv g5lRk821ZCNBosfRUvcMXoY6lTwHLIDrEfkJQtjxfdTlWQdwr0mM5ye7vd83AManSQwutgpI q+wE8CNY2VN9xAlE7OhcmWXlnAw3MJLW863SXdGlnkA3N+U4BoKQSIToGuXARQ14IMNvfeKX NphLPpUUnUNdfxAHu/S3tPTc/E/oePbHo794dnEm57LuuQINBFg2+xABEADZg/T+4o5qj4cw nd0G5pFy7ACxk28mSrLuva9tyzqPgRZ2bdPiwNXJUvBg1es2u81urekeUvGvnERB/TKekp25 4wU3I2lEhIXj5NVdLc6eU5czZQs4YEZbu1U5iqhhZmKhlLrhLlZv2whLOXRlLwi4jAzXIZAu 76mT813jbczl2dwxFxcT8XRzk9+dwzNTdOg75683uinMgskiiul+dzd6sumdOhRZR7YBT+xC wzfykOgBKnzfFscMwKR0iuHNB+VdEnZw80XGZi4N1ku81DHxmo2HG3icg7CwO1ih2jx8ik0r riIyMhJrTXgR1hF6kQnX7p2mXe6K0s8tQFK0ZZmYpZuGYYsV05OvU8yqrRVL/GYvy4Xgplm3 DuMuC7/A9/BfmxZVEPAS1gW6QQ8vSO4zf60zREKoSNYeiv+tURM2KOEj8tCMZN3k3sNASfoG fMvTvOjT0yzMbJsI1jwLwy5uA2JVdSLoWzBD8awZ2X/eCU9YDZeGuWmxzIHvkuMj8FfX8cK/ 2m437UA877eqmcgiEy/3B7XeHUipOL83gjfq4ETzVmxVswkVvZvR6j2blQVr+MhCZPq83Ota xNB7QptPxJuNRZ49gtT6uQkyGI+2daXqkj/Mot5tKxNKtM1Vbr/3b+AEMA7qLz7QjhgGJcie qp4b0gELjY1Oe9dBAXMiDwARAQABiQI8BBgBCAAmFiEEcM/SHOJt5ePBD8hO5T0WKDGD1rMF Alg2+xACGwwFCQlmAYAACgkQ5T0WKDGD1rOYSw/+P6fYSZjTJDAl9XNfXRjRRyJSfaw6N1pA Ahuu0MIa3djFRuFCrAHUaaFZf5V2iW5xhGnrhDwE1Ksf7tlstSne/G0a+Ef7vhUyeTn6U/0m +/BrsCsBUXhqeNuraGUtaleatQijXfuemUwgB+mE3B0SobE601XLo6MYIhPh8MG32MKO5kOY hB5jzyor7WoN3ETVNQoGgMzPVWIRElwpcXr+yGoTLAOpG7nkAUBBj9n9TPpSdt/npfok9ZfL /Q+ranrxb2Cy4tvOPxeVfR58XveX85ICrW9VHPVq9sJf/a24bMm6+qEg1V/G7u/AM3fM8U2m tdrTqOrfxklZ7beppGKzC1/WLrcr072vrdiN0icyOHQlfWmaPv0pUnW3AwtiMYngT96BevfA qlwaymjPTvH+cTXScnbydfOQW8220JQwykUe+sHRZfAF5TS2YCkQvsyf7vIpSqo/ttDk4+xc Z/wsLiWTgKlih2QYULvW61XU+mWsK8+ZlYUrRMpkauN4CJ5yTpvp+Orcz5KixHQmc5tbkLWf x0n1QFc1xxJhbzN+r9djSGGN/5IBDfUqSANC8cWzHpWaHmSuU3JSAMB/N+yQjIad2ztTckZY pwT6oxng29LzZspTYUEzMz3wK2jQHw+U66qBFk8whA7B2uAU1QdGyPgahLYSOa4XAEGb6wbI FEE= Message-ID: Date: Tue, 14 Apr 2020 09:54:11 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:lUbQ29bmhZJ0g5G+RZyoh8EgL+tJYj+dZipYNEU8WO1IqOSg0KA 7TKwt8wVwfL86u/NH6QEwBz6VQDTOU36sJpMXVujRbEXzD2mXXA50H4KBiVI+rEt0/Ci8Lp +C1XEq55EXsNH9XgFXNLmHOzAIkYDGpHwJJYv3I2helrl9Je0Dk9bIeza1GOyCa+CxbtPl9 rB2B98/+YtF2YP0kcus2g== X-UI-Out-Filterresults: notjunk:1;V03:K0:bhlk+O28LIA=:s/gtWVVApxLZpQILrAzXGC 2blX8565DznK7m1PCzyLmEii6uegX7NXSIoXUDHESAQmvc6CY67SsWEL3CgIHBW3nq2X5mJyW tcoyFfVda0oC6s2QD8A6foYtfANWSUsb5Nzfa9aNWrbtxnjNJ/1hsJOBCTP8z6zSDGYZG/KA7 A/9oCOJTagciDuLl18ImukSMRjmfRhbHzEa44dRab3ZSsuDDnO0kxBFaaefBMkPwu3jMRWeTv W/sSMjiO30uYziaPostJXoCDkrxNE0dUI47hMVsRKRBFKw/ShZNWmYMmuBuLUQNoAUTuy9ffR A8Qc4ePTHitaZcXnE8i22b8Uwd7Ru4urlXWBMHMf4J5QAaMp6z+wVrMKmJc0OmR53DOKJocqy +kqQGtFWIR+9FS+ffUn78zJG0hNpWyznrUZ/KU+A4SjOwgbcmtjfpqC2g7eusRFNWNkQWZHfq YqdZI1KLpi5s7yjYw+VPUC4uAGfw9zpxRZLuRRLkOxXLievx7bvyvsiubjMhkVVXCcUz8ZxAe kd6O9wMiF8DuUlekp6IkyqArFOFPuT2Dh9yTY43NtcClswnMsf5cQ7cQu119GPwgGtMU3ohke LIF4fXhBvvi+Pv8BcmvA7eDYiJdhuhie0M5+w2ECSygOzv44C5OdlNcvweNZj6DjuuQBbN6E+ Hu4OUB1HFDUP4Le92v6zzVTbK7g4ffHmcsAxdAROrmPJ0MQ3lMtXLVIeBuTnuTL6WUjvCHYPT 7ijcGq4WEcTQzlpqfLgYx61t2Z322ezH605hPe9JoizIrexihjwHPZyqMaaJ88B7AaQTds6GD v2IePgm0iheS3ZKeotjh/RF7Penel1+YTLCzt7/7YJw4oRpXePAeb/ltmoXggBbdX9hLSYgRU 8HCMLgiVTj1FtimkL4ZRTHivIj23Wb4+ALr+esCXOM5BDc+vq7Gx2anW3T8tj3LAg7i5d5rfG ASgd3ls3VUnYs1W1rcTQXTnma9eheX5GXFSnXEpL7GhS2pVIGuhCnxXNre44BrYVLmNdFni5F qN/FUUcXuYLxqj527B+DLh/RM3D1BWAclwA1OB+/T4+aVWe9vRjKm0lB3BL1CrUVg/MYluPEV Rm1epQmYlLFrqiUylATe5JP9QpykLJgBUNn+EdYOGl0MM1I5tij0hLX+oxIGmBxWdAhBbdg9v dWdLCCOWGcMjiLV3MJhdqJk6BOXCNj+vdlL55C/D02pLmc1eMa+sq2pvu6QA9CJY02J3BTj2S H6hn6tw5KSDTC+8+q Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Traced event can trigger 'snapshot' operation(i.e. calls snapshot_trigge= r() I suggest to improve the change description. * Adjustment: =E2=80=A6 operation (i. e. =E2=80=A6 * Will the tag =E2=80=9CFixes=E2=80=9D become relevant? Regards, Markus