From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.15.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9ACCE6DD09; Fri, 12 Jan 2024 15:00:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=web.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b="ocbJzJk3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=s29768273; t=1705071632; x=1705676432; i=markus.elfring@web.de; bh=mZfbtSP2eLg7KULWpeXHehpSY+IdUn5/j3kjnvUcs2I=; h=X-UI-Sender-Class:Date:Subject:To:Cc:References:From: In-Reply-To; b=ocbJzJk3E7Vjj0p1kohA3nFwk/dy8MbzNeqmc5vT8VkFWdJGEJa5IQXTJk6e2l5a PWXo8n7ApYh9dgzwcK6XAu4VXSbXjt55zJbXkIZHudLUM1meXRGdRN5pkZlO2072O /5UQ5uykB0Q8ApIKL9L9H1YWNBlAj44lR9tuZ+oYS0X6LeBQMH7z75+Lx1Dfw+Stm ur3acoNoyc3bQGi1XOBCOE9Qbe3bksHoX9sTrRQGXMzy93WQyHwMpFfYz/bYIp5R6 Uepa2vyPvbJT46e1lxpHjlKZ7VdmIcKl9VUVA5MPW1UXkIWOqFsLfLhJ4uXdI+vVP p+qH3iFmSGoHCKr4ZQ== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.91.95]) by smtp.web.de (mrweb005 [213.165.67.108]) with ESMTPSA (Nemesis) id 1N7gXO-1r2wjF43rm-01558N; Fri, 12 Jan 2024 16:00:32 +0100 Message-ID: <96e1e30a-ae2f-4dfb-9a1c-edaf6b8e1231@web.de> Date: Fri, 12 Jan 2024 16:00:21 +0100 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [v2 2/2] io_uring: Improve exception handling in io_ring_ctx_alloc() To: Gabriel Krisman Bertazi , Jens Axboe , Pavel Begunkov , io-uring@vger.kernel.org, kernel-janitors@vger.kernel.org Cc: LKML References: <6cbcf640-55e5-2f11-4a09-716fe681c0d2@web.de> <878r4xnn52.fsf@mailhost.krisman.be> <49ecda98-770d-455e-acd7-12d810280fdd@web.de> <87frz2k4jm.fsf@mailhost.krisman.be> Content-Language: en-GB From: Markus Elfring In-Reply-To: <87frz2k4jm.fsf@mailhost.krisman.be> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:3fcZXN079uvfIcjs2xVAhdFEtF5OObN5kLwIPmxpQDsZhhkZULL NZ7w4yaCeziYpmKoLQui1CfJKn80IgEQMLQg861wIvzSC7Nb5ZxgYkMYvR6P0D8y9AYyfAB kGOfFcJUP/YIIJtJS41hkuL0XRporYyhOx6l8KXpcEYxkoCy/hixa0pqdeNBJeZr4xpl5sV pQWGmRAd61sq1upCB9ArQ== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:CX07fjvmKG8=;djUVypSqjkR9zW5MJaSHacMcJBr hzFLPkxRRXiuFx0Jo4+UmKQ59SuzUOobiT8AqAiyEQ9kigZaA9Mb7c1AfdenkzU/Z4KDutFQr xPhZ1PUYg2BbFsm6Oz5Ebx8b4CWy+2w2ltSaZYVujiap0WFNQA7LkF/CeGU8+Yqvbri5whvau 4HrACfbd5ynnK0kXbfgQMwIPLdO4yQo2vOHvAlHtmNeN1thRI8EBVFVHaWDlrA4XEWEZwrbdq iTN/PbvVVG5m7la4MatvMjfNS2hJAtl+h3xxX4qgzZxq9zUYLcZPvw5DICEo1CXA8xaAKNDKj yHu86QsdJFMBChktzct3RaZ2o5o0j0U3AdaicyuQQbjQR0ILF67qBT6LXvT20DqhBYmJtaJgo HkF0z/40yQ3pJSNR2Qx4KwIC65sOzuZtxbtfrvPpuoFKeE3teQjgl3CskUzB8AfJspLD0C8dw j1KDydvXZVgSEGI333xrEogt+wUt5iG11BtPbgOwUUSjrj8M/7RAy1OsPAOId6adwi/bVt1B9 uHc98O42hIGLLFusWrmJZ7lvfFFSbaKFlrX4mtiCnb0zZbP41wQq9FGFBJnMCPK8WYE7rFM51 +6fvvQVuEfCgBxQ6Z4PA89OPBIWR/KMWLXvQ/yEEXY7csaR913ASvA3x2YB2MT1xMlPt05M44 Mo2K2NkuUfiPSK07ecKcVf3FoptwHVUzc5lib4WK7q3O+kL+QAy2Fnk23rvp7wsLrzBbbhjHL KS66N+JCKoZERCAPNx+jELvkYthb7wk37HufF3CqlvhDuYK7wGCDV6TgMEhuoc2uLiyMSPkIR CdWw4UDY+SuAc8lF8GPLKJygTvqDPtV1GfhPY4eMf719J/HzMyMlimhoeOP8BcpP03V3EkY2N MGs6OHuy21uj0sN4SuWIBcRUYGFQy6DrTlHBCpSXZOTY6fvoxkyf3uKUzWL8BvY8rnZNOyK4W bqBhTQ== >> The label =E2=80=9Cerr=E2=80=9D was used to jump to a kfree() call desp= ite of >> the detail in the implementation of the function =E2=80=9Cio_ring_ctx_a= lloc=E2=80=9D >> that it was determined already that a corresponding variable contained >> a null pointer because of a failed memory allocation. >> >> 1. Thus use more appropriate labels instead. >> >> 2. Reorder jump targets at the end. >> > > As I mentioned on v1, this doesn't do us any good, I dare to present other development views. > as kfree can handle NULL pointers just fine, Yes, this is the case. Would you dare to categorise such a special function calls as redundant? May it be skipped in more cases? > and changes like this becomes churn later when backporting or modifying = the code. There are usual opportunities to consider for further collateral evolution= . Regards, Markus