From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) (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 129DC83A0A for ; Fri, 3 May 2024 23:21:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714778484; cv=none; b=lzDwf0ZU7RrLw3ZvCPDWm6egwNnNoOUyDv9SwuJ3ojXPcsu3Fimiac0RtGQSoV6byMYxgkEEa+0UHt6h7kcNnG7JHvskM5kxu4380Zl0rHmtZq0QpfgiVJTxvTWAayWsMMq3bNVvlnGVUlpPCBf9LA+0qhypsCmAYDGLerXZxmg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714778484; c=relaxed/simple; bh=JFz4W1O7PBh1TWuHYSTsZl3JZ4bwL07AsyYT8GjzFs0=; h=MIME-Version:From:Date:Message-ID:Subject:To:Content-Type; b=j2lkeuKfJgFx4TWv6LK/pbaWUtbw/UIziDkFE4h3HICqHCal8qNmqqUBduPZlprM5qoNHbouQzY41y6QF7I88rxZEzZkRuiu4t1U8qqbB5J0vOSRAtKmD0ech9js5FsYXD8xl/pUnniGR7D7Vlo9gFaG+rQa/lHIN6mvGc2R0AA= 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=ntOEVPHh; arc=none smtp.client-ip=209.85.214.177 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="ntOEVPHh" Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-1e5c7d087e1so1584435ad.0 for ; Fri, 03 May 2024 16:21:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1714778482; x=1715383282; darn=vger.kernel.org; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=lCOduIamhHxZX+BXYRZ0ol9/CGuEvzTDNoGxS5VMHo0=; b=ntOEVPHh9wQQzNj9KqcqfsASxKaadnZuiscTwQrWdFDuofhnkIfBJ54oPxkIx0JL5x pddkw4+fWFhdwLNEAnaigxQeWxcqzmiDOhpZzpadJw1IrS3Jl2h/LZ8zvSueYiaZyaWb hplNmCIWOB/rdmooPDncIw362fcNi4jT6CvI9PM+xhWJTiTg79ryAsTOT7v1Nw5eDUCL ss9Kzy325MEqQh8so6wY7A02zYkWM6jbhQ62Ho1hq8TT2QcROuq9TPPzmvskSfh3bczi XPt42ajp60bqHnNmfXgBtpC5m5jti9a09FiiXcsjhdOyfBkjtT6ESAFZhaEOQVQhV2bC gAsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1714778482; x=1715383282; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=lCOduIamhHxZX+BXYRZ0ol9/CGuEvzTDNoGxS5VMHo0=; b=mNt2UvZ/luCk5mizd+aU03gLN51j/nAAZCbfdFSMJRLyRHINq8LudOhx02WO9yNIJF KCCJ0kv/cPuAmctQVenlnGtcun5G5ZzQB2J5ELxm4Jg9bKmRyK4EcU9dyy2qXjXri0Nj P7kmgykA/J6ZLWmg0HqYWjG3/ZYmdmBfjT9fvmfCAHUT/lTeWkwliLL5XZqbco/UfpHW G8eyJUwMqfiMtPsFK8NDM3YHYHSyNx+6w9ZKvnaJMqMzNDNcVp3YKyogOWLcUjQlngYf QmenuvnrCCNi0aKcvec/OTrDVUZ3IrVj1SKf4OxJRyVDPHG/a8uvbLZSH1qVD0smJUUp sDGQ== X-Gm-Message-State: AOJu0YznxHFVqhqKd/0YBMhU0vNSGVsAEwAC/K+GMSPpOuwXzZf7SUYn yxq1GxpZdKzhOOWpqSWWpQmqC/lXIBaojlMwvjJwVCFjdlURTui9y8/MYX0DJeaCrkvX8JYEM61 Rs1tswLhXzGM7eJJuly08Sqwo5mCXQe+8 X-Google-Smtp-Source: AGHT+IGErYnITxOf0CvAioqSn/pD7q+jGCjfw3FqlJTu1zVkC6du6QDpoeBsQbzxptXgai/nKdO02AVoy0TYoPZajXs= X-Received: by 2002:a17:90a:4bc8:b0:2b2:812d:dccc with SMTP id u8-20020a17090a4bc800b002b2812ddcccmr4088510pjl.13.1714778481971; Fri, 03 May 2024 16:21:21 -0700 (PDT) Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Alexander Babayants Date: Sat, 4 May 2024 02:21:10 +0300 Message-ID: Subject: Submitting IO events with IORING_FEAT_NODROP and overflown CQ ring To: io-uring@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Hi! Per io_uring_setup(2): > IORING_FEAT_NODROP ... > If this overflow condition is entered, > attempting to submit more IO will fail with the -EBUSY > error value, if it can't flush the overflown events to the > CQ ring. If this happens, the application must reap events > from the CQ ring and attempt the submit again. But I'm not getting -EBUSY on a 6.2 kernel when submitting to the ring with a full CQ ring and an overflow flag set. I'm not an expert in uring code, but it seems the error was removed in commit 1b346e4aa8e79227391ffd6b7c6ee5acf0fa8bfc. Could you please check if I'm right and if that change was intentional? -- Regards, Alexander Babayants.