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 X-Spam-Level: X-Spam-Status: No, score=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5CC4C433DB for ; Wed, 27 Jan 2021 21:54:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABA806146D for ; Wed, 27 Jan 2021 21:54:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236398AbhA0VyK (ORCPT ); Wed, 27 Jan 2021 16:54:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234982AbhA0VyD (ORCPT ); Wed, 27 Jan 2021 16:54:03 -0500 Received: from mail.kapsi.fi (mail.kapsi.fi [IPv6:2001:67c:1be8::25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCEA6C06174A for ; Wed, 27 Jan 2021 13:53:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kapsi.fi; s=20161220; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=RzYqJl+q1gCm+1GGVn7zeM+eQJYxs7B083hKM09xL6k=; b=oZOh2HvvspN52yo1o/O/dpvVZJ QpjKz7xh0L/jQQsoDCEdV3GS6dl3OvHplPiMrhWn97CST69eSmqDSUlwqXbST5mO33z3NSYmjbWJW MljqJYmAICz7QaeXicM9kygZBoO/GzFL0Gk5lQXPwxSEQt0x7JqMpoj8BaeJVd/Q6QG0+nKRhQeFj d/2BrzMi7u7Y1ybeyJKx4uW5WgzkPGec48/7cVP5U8gToME2g+U5z3cwQBiVaD/uHUlI5P6vY3hfx 6jsbPqYhsOWXQYcrhcByffF0+zPRiJFfIttzF60TOmlymD1b8UFbYWV2OP9/F8nxS6Mb/6kbJA7rT vbkWid8w==; Received: from dsl-hkibng22-54f986-236.dhcp.inet.fi ([84.249.134.236] helo=[192.168.1.10]) by mail.kapsi.fi with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1l4skW-0007Ox-Sg; Wed, 27 Jan 2021 23:53:16 +0200 Subject: Re: [PATCH v5 00/21] sync_file API is not very suitable for DRM To: Dmitry Osipenko , Mikko Perttunen , thierry.reding@gmail.com, jonathanh@nvidia.com, airlied@linux.ie, daniel@ffwll.ch Cc: linux-tegra@vger.kernel.org, dri-devel@lists.freedesktop.org, talho@nvidia.com, bhuntsman@nvidia.com References: <20210111130019.3515669-1-mperttunen@nvidia.com> <2f999b6d-d781-503a-78f4-d444bce72c58@kapsi.fi> From: Mikko Perttunen Message-ID: <53b7c991-7aa7-2407-eb54-d9db997f00e7@kapsi.fi> Date: Wed, 27 Jan 2021 23:53:16 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 84.249.134.236 X-SA-Exim-Mail-From: cyndis@kapsi.fi X-SA-Exim-Scanned: No (on mail.kapsi.fi); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org On 1/27/21 11:35 PM, Dmitry Osipenko wrote: > 26.01.2021 05:45, Mikko Perttunen пишет: >>> 4. Sync file shouldn't be needed for the part of DRM API which doesn't >>> interact with external non-DRM devices.  We should use DRM syncobj for >>> everything related to DRM, it's a superior API over sync file, it's >>> suitable for DRM scheduler. >> >> Considering the issues with fileno limits, I suppose there is no other >> choice. Considering the recent NTSYNC proposal by Wine developers, maybe >> we should also have NTHANDLEs to get rid of restrictions of file >> descriptors. > > It's odd to me that you trying to avoid the existing DRM API. This all > was solved in DRM long time ago and grate drivers have no problems with > using the DRM APIs. Even if something is really missing, then you should > add the missing features instead of re-inventing everything from scratch. > DRM is only one of many subsystems that will have to deal with syncpoints, so I have wanted to have a central solution instead of reimplementing the same stuff everywhere. sync_files seem like the "missing feature", but they are difficult to use it with the fileno limits. But as has been said many times, they are intended only to transfer fences between the implementations in individual drivers, so I guess I will have to abandon this dream. >> DRM syncobjs may have some advantages over sync files, but >> also disadvantages. They cannot be poll()ed, so they cannot be combined >> with waits for other resources. > > I'm not sure do you mean by "poll". Sync object supports polling very well. > I mean the poll/select etc. series of functions, which wait for file descriptors to become ready. If there's some trick that allows syncobjs to be used for that, then please tell. Mikko 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 X-Spam-Level: X-Spam-Status: No, score=-5.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24A70C433E0 for ; Wed, 27 Jan 2021 21:53:22 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id DB8D96146D for ; Wed, 27 Jan 2021 21:53:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB8D96146D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kapsi.fi Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 41A1389CCB; Wed, 27 Jan 2021 21:53:20 +0000 (UTC) Received: from mail.kapsi.fi (mail.kapsi.fi [IPv6:2001:67c:1be8::25]) by gabe.freedesktop.org (Postfix) with ESMTPS id B33336E8AF for ; Wed, 27 Jan 2021 21:53:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kapsi.fi; s=20161220; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=RzYqJl+q1gCm+1GGVn7zeM+eQJYxs7B083hKM09xL6k=; b=oZOh2HvvspN52yo1o/O/dpvVZJ QpjKz7xh0L/jQQsoDCEdV3GS6dl3OvHplPiMrhWn97CST69eSmqDSUlwqXbST5mO33z3NSYmjbWJW MljqJYmAICz7QaeXicM9kygZBoO/GzFL0Gk5lQXPwxSEQt0x7JqMpoj8BaeJVd/Q6QG0+nKRhQeFj d/2BrzMi7u7Y1ybeyJKx4uW5WgzkPGec48/7cVP5U8gToME2g+U5z3cwQBiVaD/uHUlI5P6vY3hfx 6jsbPqYhsOWXQYcrhcByffF0+zPRiJFfIttzF60TOmlymD1b8UFbYWV2OP9/F8nxS6Mb/6kbJA7rT vbkWid8w==; Received: from dsl-hkibng22-54f986-236.dhcp.inet.fi ([84.249.134.236] helo=[192.168.1.10]) by mail.kapsi.fi with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1l4skW-0007Ox-Sg; Wed, 27 Jan 2021 23:53:16 +0200 Subject: Re: [PATCH v5 00/21] sync_file API is not very suitable for DRM To: Dmitry Osipenko , Mikko Perttunen , thierry.reding@gmail.com, jonathanh@nvidia.com, airlied@linux.ie, daniel@ffwll.ch References: <20210111130019.3515669-1-mperttunen@nvidia.com> <2f999b6d-d781-503a-78f4-d444bce72c58@kapsi.fi> From: Mikko Perttunen Message-ID: <53b7c991-7aa7-2407-eb54-d9db997f00e7@kapsi.fi> Date: Wed, 27 Jan 2021 23:53:16 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-SA-Exim-Connect-IP: 84.249.134.236 X-SA-Exim-Mail-From: cyndis@kapsi.fi X-SA-Exim-Scanned: No (on mail.kapsi.fi); SAEximRunCond expanded to false 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: linux-tegra@vger.kernel.org, talho@nvidia.com, bhuntsman@nvidia.com, dri-devel@lists.freedesktop.org Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" T24gMS8yNy8yMSAxMTozNSBQTSwgRG1pdHJ5IE9zaXBlbmtvIHdyb3RlOgo+IDI2LjAxLjIwMjEg MDU6NDUsIE1pa2tvIFBlcnR0dW5lbiDQv9C40YjQtdGCOgo+Pj4gNC4gU3luYyBmaWxlIHNob3Vs ZG4ndCBiZSBuZWVkZWQgZm9yIHRoZSBwYXJ0IG9mIERSTSBBUEkgd2hpY2ggZG9lc24ndAo+Pj4g aW50ZXJhY3Qgd2l0aCBleHRlcm5hbCBub24tRFJNIGRldmljZXMuwqAgV2Ugc2hvdWxkIHVzZSBE Uk0gc3luY29iaiBmb3IKPj4+IGV2ZXJ5dGhpbmcgcmVsYXRlZCB0byBEUk0sIGl0J3MgYSBzdXBl cmlvciBBUEkgb3ZlciBzeW5jIGZpbGUsIGl0J3MKPj4+IHN1aXRhYmxlIGZvciBEUk0gc2NoZWR1 bGVyLgo+Pgo+PiBDb25zaWRlcmluZyB0aGUgaXNzdWVzIHdpdGggZmlsZW5vIGxpbWl0cywgSSBz dXBwb3NlIHRoZXJlIGlzIG5vIG90aGVyCj4+IGNob2ljZS4gQ29uc2lkZXJpbmcgdGhlIHJlY2Vu dCBOVFNZTkMgcHJvcG9zYWwgYnkgV2luZSBkZXZlbG9wZXJzLCBtYXliZQo+PiB3ZSBzaG91bGQg YWxzbyBoYXZlIE5USEFORExFcyB0byBnZXQgcmlkIG9mIHJlc3RyaWN0aW9ucyBvZiBmaWxlCj4+ IGRlc2NyaXB0b3JzLgo+IAo+IEl0J3Mgb2RkIHRvIG1lIHRoYXQgeW91IHRyeWluZyB0byBhdm9p ZCB0aGUgZXhpc3RpbmcgRFJNIEFQSS4gVGhpcyBhbGwKPiB3YXMgc29sdmVkIGluIERSTSBsb25n IHRpbWUgYWdvIGFuZCBncmF0ZSBkcml2ZXJzIGhhdmUgbm8gcHJvYmxlbXMgd2l0aAo+IHVzaW5n IHRoZSBEUk0gQVBJcy4gRXZlbiBpZiBzb21ldGhpbmcgaXMgcmVhbGx5IG1pc3NpbmcsIHRoZW4g eW91IHNob3VsZAo+IGFkZCB0aGUgbWlzc2luZyBmZWF0dXJlcyBpbnN0ZWFkIG9mIHJlLWludmVu dGluZyBldmVyeXRoaW5nIGZyb20gc2NyYXRjaC4KPiAKCkRSTSBpcyBvbmx5IG9uZSBvZiBtYW55 IHN1YnN5c3RlbXMgdGhhdCB3aWxsIGhhdmUgdG8gZGVhbCB3aXRoIApzeW5jcG9pbnRzLCBzbyBJ IGhhdmUgd2FudGVkIHRvIGhhdmUgYSBjZW50cmFsIHNvbHV0aW9uIGluc3RlYWQgb2YgCnJlaW1w bGVtZW50aW5nIHRoZSBzYW1lIHN0dWZmIGV2ZXJ5d2hlcmUuIHN5bmNfZmlsZXMgc2VlbSBsaWtl IHRoZSAKIm1pc3NpbmcgZmVhdHVyZSIsIGJ1dCB0aGV5IGFyZSBkaWZmaWN1bHQgdG8gdXNlIGl0 IHdpdGggdGhlIGZpbGVubyAKbGltaXRzLiBCdXQgYXMgaGFzIGJlZW4gc2FpZCBtYW55IHRpbWVz LCB0aGV5IGFyZSBpbnRlbmRlZCBvbmx5IHRvIAp0cmFuc2ZlciBmZW5jZXMgYmV0d2VlbiB0aGUg aW1wbGVtZW50YXRpb25zIGluIGluZGl2aWR1YWwgZHJpdmVycywgc28gSSAKZ3Vlc3MgSSB3aWxs IGhhdmUgdG8gYWJhbmRvbiB0aGlzIGRyZWFtLgoKPj4gRFJNIHN5bmNvYmpzIG1heSBoYXZlIHNv bWUgYWR2YW50YWdlcyBvdmVyIHN5bmMgZmlsZXMsIGJ1dAo+PiBhbHNvIGRpc2FkdmFudGFnZXMu IFRoZXkgY2Fubm90IGJlIHBvbGwoKWVkLCBzbyB0aGV5IGNhbm5vdCBiZSBjb21iaW5lZAo+PiB3 aXRoIHdhaXRzIGZvciBvdGhlciByZXNvdXJjZXMuCj4gCj4gSSdtIG5vdCBzdXJlIGRvIHlvdSBt ZWFuIGJ5ICJwb2xsIi4gU3luYyBvYmplY3Qgc3VwcG9ydHMgcG9sbGluZyB2ZXJ5IHdlbGwuCj4g CgpJIG1lYW4gdGhlIHBvbGwvc2VsZWN0IGV0Yy4gc2VyaWVzIG9mIGZ1bmN0aW9ucywgd2hpY2gg d2FpdCBmb3IgZmlsZSAKZGVzY3JpcHRvcnMgdG8gYmVjb21lIHJlYWR5LiBJZiB0aGVyZSdzIHNv bWUgdHJpY2sgdGhhdCBhbGxvd3Mgc3luY29ianMgCnRvIGJlIHVzZWQgZm9yIHRoYXQsIHRoZW4g cGxlYXNlIHRlbGwuCgpNaWtrbwpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVlZGVz a3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9k cmktZGV2ZWwK