From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f50.google.com (mail-ed1-f50.google.com [209.85.208.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 245221CF7BC for ; Fri, 11 Oct 2024 21:38:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728682709; cv=none; b=ttXxYnFDqWuTpCYp+ltuPXo7IdyC2B607tC9/EQQF1tqGtdv/dUNRkRDJZ/FNzlYgXfqsLl0W5EsFDQk95JN3rbxWHcMcjFvzDTsRCJXbJ6B402Z4xMrSpJo5rGVhsDpIwgztrIpsnnPQRhg6nkdtSyhO21Gh01QhGgHlUdH2TM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728682709; c=relaxed/simple; bh=yq+iA7obx5qu+EWHRyDrGUnwTQyEjaYDg5Td5yaL7B0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UNPcCdq5a4NdmjsTPdsKAuxydU5VvAG/vtpYeMfrXGb67CAmw0Csz03dIIT78KT4MX4hOUnxNHBleNWaKWiqmWgLxnzOmmyRtkSf3A1kaXvpYztcntRDbvFqor3vkduy/Y5/kkzLPZDKcTJkvY1We72bXujWr0kDcNG2Z4bFIRs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Dg3GKUYP; arc=none smtp.client-ip=209.85.208.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Dg3GKUYP" Received: by mail-ed1-f50.google.com with SMTP id 4fb4d7f45d1cf-5c721803a89so3358562a12.1 for ; Fri, 11 Oct 2024 14:38:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728682705; x=1729287505; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=/ezX1BK8VWUms9bu7sFqQ55U0b5j0mewquCGqW0+IeE=; b=Dg3GKUYP2WOfoq/tSvSDYqikOZFqlTrVSXGHbjnk26ZKKrLI1J4mdoL/56o0L9hW1y xz0991oAYbuZixD15z38Yfh/irICCS46jmWH62g1bvegeFnunWHJPK/XdAVzh8niPV/q 5JEOrvPaiW5FX7999437D7QLWmtJk9W+unqwmjJpynsOzIwjviG/riZRk5fc5u2xiUnd MmxSwiS2fPEZRUaJBmx3bn8DVK1wjhK5ESVPehAFENLz/PdLxk3LCYBF8jGmZ11TQJZf H18qCGXMck1zxTybMEuyRUtiL25AUOGT8zFx2sObm/gKmyUM+F0sk3v+9ucUR39ELZR/ I6Lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728682705; x=1729287505; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=/ezX1BK8VWUms9bu7sFqQ55U0b5j0mewquCGqW0+IeE=; b=BTDaue7Vithw2cwfFo+/WYXhv8Fz+R2iX/NtLQAn2zC/CYt+ZtLcY9LTO4//8ofj8I +ILjoZSzQp2983iqXu4WjQ+PFp4HIqD9hUhwI0gniOdavSopADOvaGlAhZwv7L+0I8QE XFpSjnlPVTJqpu6Gx2/HbytmC7cHms5vBNTEgzhhz0RAaFpksXTd/ghCJaNHB7AmcnJN YwtF551XF1bXrnfVnyPYPNEh9KMX1XU15DlJEcinwT2K/V2GtwF4xI3BBh/gzNAwtMxM 1PwA6t1HEpLwjgFuIk1SUgXqzlssway6KaBTuAgNJW0+k6tQwZFn7Kk2/stEj2z4aqht 8Kmw== X-Forwarded-Encrypted: i=1; AJvYcCXIy8PChDLzN6I3pBe26zSuKWxAEA6vn5X2uYJv/Lj7l8rFshlJnxWhQHGFqSiILrjE/59ZM308bA==@vger.kernel.org X-Gm-Message-State: AOJu0YyLc7GP9VEbOHaWw+flXsV5KsA54lduDs1NQ9jat689hNDHXdSN 6j4jApbXhYbyen2Mf0OMGnJXfXubUGtIonlm8wNAXAAyaYKj100SmhxQgg== X-Google-Smtp-Source: AGHT+IG0U6PEKyEpVHTkLs4wG10hBkCd5O39efW0YlT24T5Z9kpLMvJxrbZ78Qeze8VN9atpQzrgmg== X-Received: by 2002:a17:907:3da3:b0:a99:5ad9:b672 with SMTP id a640c23a62f3a-a99e3b20bfcmr89845266b.10.1728682705136; Fri, 11 Oct 2024 14:38:25 -0700 (PDT) Received: from [192.168.42.194] ([148.252.140.94]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a99a7edea69sm252891866b.7.2024.10.11.14.38.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 11 Oct 2024 14:38:24 -0700 (PDT) Message-ID: <98b1e1b1-ec11-490e-b1e7-46b75d6584ee@gmail.com> Date: Fri, 11 Oct 2024 22:38:57 +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: Large CQE for fuse headers To: Bernd Schubert , io-uring@vger.kernel.org Cc: Jens Axboe , Miklos Szeredi , Joanne Koong , Josef Bacik References: Content-Language: en-US From: Pavel Begunkov In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/10/24 21:56, Bernd Schubert wrote: > Hello, > > as discussed during LPC, we would like to have large CQE sizes, at least > 256B. Ideally 256B for fuse, but CQE512 might be a bit too much... > > Pavel said that this should be ok, but it would be better to have the CQE > size as function argument. > Could you give me some hints how this should look like and especially how I remembered it as SQEs, which would've been much easier. In the current io_uring infra, usually to post a cqe an opcode specific path stashed the result value in the request structure and then the core io_uring code will post it for you. We won't find space for 256B, however, and it'd need to happen right from the cmd path and follow the rules when / from what context it can be posted. I'll take a stub to see how it can look like. > we are going to communicate the CQE size to the kernel? I guess just adding > IORING_SETUP_CQE256 / IORING_SETUP_CQE512 would be much easier. 3-4 special cases is already odd as an API, we should rather just pass the desired CQE size. > I'm basically through with other changes Miklos had been asking for and > moving fuse headers into the CQE is next. -- Pavel Begunkov