From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f42.google.com (mail-lf1-f42.google.com [209.85.167.42]) (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 59987166F00 for ; Fri, 20 Sep 2024 12:54:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726836879; cv=none; b=s/gZaKg67E6FOJKRenHmQx/0K9VrLM47F/Dk+PAWwyAbmGoIBmm7rhpHFLy5JCJIdxsDuZNEZ3dERasvoJQpGa3il/hoIjhS39kVMtl79oNx2onV8bYbvo+ard086SPGX4NSB/Ronfw0ZgyzamGrBHtddTNiMyVpbEAvWSmCa9w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726836879; c=relaxed/simple; bh=92w6dv+VseI/pBpQZrtGVh/yup0MAZCj8HPO1uZ7qiY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=FmEYqbnYtQ6Uymv9P5yXVtrUE9We/kmtsAm8jnaEsHodievy1bivt4ay4xvgVlVjFF1RUGH5+6qbirf0UfIzBscIxbNKZqvzXNBCe8ClndLJE70WnMezaSj0b/dfxrKy63tGiJBIqxl2L5R7JacJddu1ZVtduBzkCAhXOrygW8I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca; spf=pass smtp.mailfrom=ziepe.ca; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b=ba25d8VN; arc=none smtp.client-ip=209.85.167.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="ba25d8VN" Received: by mail-lf1-f42.google.com with SMTP id 2adb3069b0e04-536748c7e9aso2701465e87.0 for ; Fri, 20 Sep 2024 05:54:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1726836875; x=1727441675; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=VxOJXXuTPtJD2C97fiCxabtfgKFUIiIOX78ur33VM08=; b=ba25d8VNBKk9n0uCLfXpiXxuEHJCMZJSK3kFrY5y7AvDp4JfKnBadZ/Av9wmF8YpQO HIUOaZDFK/VGXzaWIF4+REx+ixVea3xb1HP8TR+ioUZnCwt4lFLcG80C0RNwb/BuhppZ WRHH4lLMGxwOuCmUpFJkYIoJvlCcnNynwZuuMvUoGLs/3uHJZTk2eHx3nNVpZdwrA9FB H+4+/EYMAIfZQSaOdhCSuLUPKWI+cEx9icKAF+9fRpTfQkED0rM7u7smzboX6Ep5Q2EN GwgfpWF7qiCQ2dH/ASn+ZyPn6jBVcGTerRfrzFEP1pp4vnlEKgsVZy6h8M4kf0j23AfG zVtA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726836875; x=1727441675; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=VxOJXXuTPtJD2C97fiCxabtfgKFUIiIOX78ur33VM08=; b=WgIa5rqA4zbyevxr+tfd0rAk+bja4zWNtirU1JKUzq/z+7xu56oDH4X6yMRvuUokMa e7Sf+oIkC+EKxnRVb+Jc3OsKPPX/Nw4G4t04L+iDg8+fTne3uEif8Ujv9kWRJg+ng2r3 HkULY3QoIY0AQ3uHufxiSzQDjoJJqX7ONjXGOvC2LsVyQyVNSv4SMMwuZHeaqF30TjQf zxc2hnsqIfjIRfy8m24qZ42oiZKbsjUcW75D2fUVKPgx32LRoeD5/xfoieY70IDPngjq MAoBH0NWSIG623/GllZc/dQSui8dT7C9Ky+J6DgrxKAPTTddFzjjLhCJRdp8Pyw8RP4+ rWMA== X-Forwarded-Encrypted: i=1; AJvYcCXLOW7OvUmiobQPZT9kLO1fGkGketh+AYyvn5enhMRfSUvvgrvbM8dacl30JRBOykwhkTH4kg==@lists.linux.dev X-Gm-Message-State: AOJu0Yz38tS9LxiqTfLvFyrexpbUAOydmasLQYj7lqEgP9mrhsWyyngK OWXsYR1hPHckfgAJqFrGjqso5bw3od7bDb5GLCIxLchDRfKXV1khsuz4R3Fs3s0= X-Google-Smtp-Source: AGHT+IHOG14KF21RzqtJPgrK582YmG8ObcTpDLjYz0OHoTRqntbt5Q6vcnyU0BwEDB79I9PC0gWfDg== X-Received: by 2002:a05:6512:acd:b0:535:65ce:e901 with SMTP id 2adb3069b0e04-536ac2d6791mr1966041e87.4.1726836875496; Fri, 20 Sep 2024 05:54:35 -0700 (PDT) Received: from ziepe.ca ([83.68.141.146]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5c42bb497adsm7145406a12.14.2024.09.20.05.54.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Sep 2024 05:54:34 -0700 (PDT) Received: from jgg by jggl with local (Exim 4.95) (envelope-from ) id 1srd9e-0001AK-AT; Fri, 20 Sep 2024 09:54:34 -0300 Date: Fri, 20 Sep 2024 09:54:34 -0300 From: Jason Gunthorpe To: Baolu Lu Cc: "Tian, Kevin" , "j.granados@samsung.com" , David Woodhouse , Joerg Roedel , Will Deacon , Robin Murphy , Klaus Jensen , "linux-kernel@vger.kernel.org" , "iommu@lists.linux.dev" Subject: Re: [PATCH v2 1/5] iommu/vt-d: Separate page request queue from SVM Message-ID: References: <20240913-jag-iopfv8-v2-0-dea01c2343bc@samsung.com> <20240913-jag-iopfv8-v2-1-dea01c2343bc@samsung.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Sep 18, 2024 at 07:17:32PM +0800, Baolu Lu wrote: > > more than that... for each IOMMU the current code allocates 16 pages > > and 1 hwirq. Those are unnecessary burdens in majority deployments > > which don't support/require I/O page faults. > > Yeah! I only focused on the kernel binary size but ignored these system > resources consumed by IOPF. Then, perhaps If you care about runtime overhead it should be delt with by dynamically allocating the memory and enabling it, not via kconfig We can dynmaically add IRQS in some cases now for instance Jason