From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 297BAC433EF for ; Fri, 13 May 2022 09:22:26 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3D3DC10F13D; Fri, 13 May 2022 09:22:25 +0000 (UTC) Received: from mail-qk1-x72f.google.com (mail-qk1-x72f.google.com [IPv6:2607:f8b0:4864:20::72f]) by gabe.freedesktop.org (Postfix) with ESMTPS id A04CA10F13D for ; Fri, 13 May 2022 09:22:23 +0000 (UTC) Received: by mail-qk1-x72f.google.com with SMTP id a22so6638713qkl.5 for ; Fri, 13 May 2022 02:22:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Wk6/sho0Qd9TQa3MQ3d5o7rj+3fZFRDxiENmEcRCfGM=; b=XAKnvzSpVRbvrUw7WgwcL5gkEMAZr8G6D6JzL/9IGq/Y9/kS3Sa+pU9ahtyWk+XzoW +mfalTCMfEHMY0PMA4oT7zcfo5SxtsbNtmJsswNKbZmsfmCCVVPO+guYU/XacXjkE6sw hZnHogcxAoqIRSGm4da1FIXkocDRJlPHIf4M6q0e3YrI0hcBWDMDIIcNoyIKow4/OXqR JOxgdK2PtUAjEBJ/pIryXe8SNoVd19WuK/1FMAapfkPrrgp1sUTUzL+vLbfRhVRn/032 UPDlW0jSPmVpiosIcGATaY7hFp7jR92VbmBpVqGXLgxqEZ6diJeUEInR2/dnt9qFz5Cs MGCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Wk6/sho0Qd9TQa3MQ3d5o7rj+3fZFRDxiENmEcRCfGM=; b=f/gu12B+9uQigdSmuu4BtG1H0JlIeofrgZEKACTibAOewKz7LVRfTNqAiVwK2Stmks cSJ993spjDYUFv3k6SL3fyaRCbpUVDdlq2fzBr4mnlJai62Hyi9UwqprbFhbMrjzniQh IWCssGIxnoveUrJeYReRJZDnmI3zhzV1AwFPW8bjQRIhRTWHEbLHm4o0Qy738YI2rGQu Flv/25iXPPiO6d1O41zta0FwepNwMeiUf6R9OhFD0sUsiPHcwNSEmyDvLpVSXSkj6frV KF692krKlPvQhheXJ54ximRtqLheoHRZmhsYnbMBhhVMyBnWJmcMycxiCMsj+ait7NZc bAtw== X-Gm-Message-State: AOAM530CFT9JVyrTDJKiVPCf57TTN8+0Q1c00sCmL39b1PMA0+9l06wu LUVl8nhHelgSXO/76826YXIcX5aHj5TJF5mIyvA= X-Google-Smtp-Source: ABdhPJwwXXRNdtPBoJX6hJrxR1E+p4nYuz9F0Ay5Eg/0u31Kjkvi79EXOtPTdHdoNvH2n1chO4Pg9C3HT8b6FvgKETU= X-Received: by 2002:a05:620a:f0d:b0:67e:1961:b061 with SMTP id v13-20020a05620a0f0d00b0067e1961b061mr2948676qkl.82.1652433742759; Fri, 13 May 2022 02:22:22 -0700 (PDT) MIME-Version: 1.0 References: <20220509130951.486344-1-christian.koenig@amd.com> In-Reply-To: <20220509130951.486344-1-christian.koenig@amd.com> From: Matthew Auld Date: Fri, 13 May 2022 10:21:56 +0100 Message-ID: Subject: Re: Improve TTMs empty object handling To: =?UTF-8?Q?Christian_K=C3=B6nig?= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Robert Beckett , ML dri-devel Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, 9 May 2022 at 14:09, Christian K=C3=B6nig wrote: > > Hi everyone, > > re-sending this because Daniel was requesting a background why this is > useful. > > When TTM creates a buffer this object initially should not have any > backing store and there no resource object associated with it. The same > can happen when a driver requests that the backing store of an object is > destroyed without allocating a new one. > > This is really useful during initial buffer creation as well as temporary > buffers and page tables which content doesn't need to be preserved when > they are evicted. > > Currently TTM allocates dummy system resources for that because drivers > couldn't handle a NULL pointer there. Audit the drivers and then clean > up TTM to stop making those dummy allocations. > > Please review and comment, Any chance we can throw this at intel-ci? Series seems to apply to drm-tip. > Christian. > >