From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2a00:1450:4864:20::444; helo=mail-wr1-x444.google.com; envelope-from=leif.lindholm@linaro.org; receiver=edk2-devel@lists.01.org Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 0A7522117D295 for ; Thu, 1 Nov 2018 03:33:02 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id d17-v6so19247179wre.11 for ; Thu, 01 Nov 2018 03:33:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Ek6nSXbokgrF3rZrbOmwdlEiBD2lzv8pUgLBnosGuRM=; b=UBWw1jnGML78DzR66WdcuLakm/dgTPkCe88NI/23jy363wcUljYyvcHpa5zMTVn/D+ nb+5UnkrqlyqIQlcb343ALnS04NDaPR/bsqO49Un7tJYiCWakrK3EFYs1PEM2ALm210i 6v3VWnbcO2K7+3oSYU9jzPVWD7Zl48kTC5b1M= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Ek6nSXbokgrF3rZrbOmwdlEiBD2lzv8pUgLBnosGuRM=; b=FUX8XtGYaZDKnkXH0K/89MXhcOov4uu0UMsBa3hzafVmVJNzFC7mH5uUZlqvCL24I+ M4PPMNbtMZiRa/uskLM6dSHFWTGrHyEdBFALUK1BNo2/6bhPHze6ZcxhCITPAprAUpAd L49xJg9Tv/0YYUk+LFOOmPYp3Dc6ZqdOc/VgNB2PbQdvHbZAop5uI27W0sb87sSGxOLB mtEKW/Wzn6Fn/nyCgbFeohTEk6hEpHHPAkpEOoiesgR8Mg1Va/AVpxX1Zb+nfARwnUcK nZKcwbcIGiNRTJh+b2Q6qppjiSHwRSy1vxzRXzo8IxBZxQrhxjAuKHbM0wHh5Brd3UO8 sliw== X-Gm-Message-State: AGRZ1gJGPNvjYDFLDVKBQf6kBVQmfCycDuRwgCjAtmRwpc1hLTWfHQar QG1fF/lzOkdHwNWipxhpZB8d9Q== X-Google-Smtp-Source: AJdET5f2ws9FPMb+8kYlUH/MecBz1HlYa28YvbPukmYAy+uSqC8TBQXlJ0SoNOldDJhgxtCGaRdgww== X-Received: by 2002:adf:f651:: with SMTP id x17-v6mr3317867wrp.229.1541068381227; Thu, 01 Nov 2018 03:33:01 -0700 (PDT) Received: from bivouac.eciton.net (bivouac.eciton.net. [2a00:1098:0:86:1000:23:0:2]) by smtp.gmail.com with ESMTPSA id d11sm4467524wrx.78.2018.11.01.03.32.59 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 01 Nov 2018 03:33:00 -0700 (PDT) Date: Thu, 1 Nov 2018 10:32:58 +0000 From: Leif Lindholm To: "Zeng, Star" Cc: edk2-devel-01 Message-ID: <20181101103258.rqruc37jhrbahbvb@bivouac.eciton.net> References: <1540561286-112684-1-git-send-email-star.zeng@intel.com> <1540561286-112684-5-git-send-email-star.zeng@intel.com> <20181030125006.4deveknlhrwehllb@bivouac.eciton.net> <962a2a90-2783-5fd1-25d2-6a834daa3f26@intel.com> <20181031120816.jmzeo67l2ij7da23@bivouac.eciton.net> <90e7a9d5-0ece-a12c-0730-e67b6dbf6505@intel.com> MIME-Version: 1.0 In-Reply-To: <90e7a9d5-0ece-a12c-0730-e67b6dbf6505@intel.com> User-Agent: NeoMutt/20170113 (1.7.2) Subject: Re: [PATCH V3 4/4] MdeModulePkg EhciDxe: Use common buffer for AsyncInterruptTransfer X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 Nov 2018 10:33:03 -0000 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Nov 01, 2018 at 09:12:04AM +0800, Zeng, Star wrote: > > > I believe the performance data really depends on > > > 1. How many AsyncInterruptTransfer handlers (the number of USB keyboard > > > and/or USB bluetooth keyboard?) > > > 2. Data size (for flushing data from PCI controller specific address to > > > mapped system memory address *in original code*) > > > 3. The performance of IoMmu->SetAttribute (for example, the SetAttribute > > > operation on Intel VTd engine caused by the unmap and map for flushing data > > > *in original code*, the SetAttribute operation on IntelVTd engine will > > > involve FlushPageTableMemory, InvalidatePageEntry and etc) > > > > > > > On an unrelated note to the concerns above: > > > > Why has a fundamental change to the behaviour of one of the industry > > > > standard drivers been pushed at the very end of the stable cycle? > > > > > > We thought it was a simple improvement but not fundamental change before > > > Eugene and Ard raised the concern. > > > > Understood. > > Thanks. :) > > > > > However, as it is changing the memory management behaviour of a core > > driver, I think it automatically qualifies as something that should > > only go in the week after a stable tag. > > > > We will need to have a closer look at the non-coherent case when Ard > > gets back (Monday). > > You mean Ard is on vacation and will be back next Monday. Yes. > > If this version causes issues with non-coherent systems, we will need > > to revert it before the stable tag. We would then need to look into > > the best way to deal with the performance issues quoted above. > > I am glad to revert it if it has side effect. Is it possible someone could > have a quick check? Ard could. It would take me much longer :) Which is why I would prefer to wait until next week. Regards, Leif