From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by gabe.freedesktop.org (Postfix) with ESMTPS id B4F7F6E02F for ; Fri, 22 Oct 2021 23:36:11 +0000 (UTC) Date: Fri, 22 Oct 2021 16:36:06 -0700 Message-ID: <87mtn0k4yh.wl-ashutosh.dixit@intel.com> From: "Dixit, Ashutosh" In-Reply-To: References: <20211021043508.1158148-1-priyanka.dandamudi@intel.com> <20211021043508.1158148-4-priyanka.dandamudi@intel.com> <20211021073321.GC3640@zkempczy-mobl2> <87y26l9atx.wl-ashutosh.dixit@intel.com> <87wnm59a0x.wl-ashutosh.dixit@intel.com> <20211022044032.GA8290@zkempczy-mobl2> MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=ISO-8859-2 Content-Transfer-Encoding: quoted-printable Subject: Re: [igt-dev] [PATCH i-g-t 3/4] lib/igt_gt: Add compute engine List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" To: Tvrtko Ursulin Cc: Zbigniew =?ISO-8859-2?Q?Kempczy=F1ski?= , priyanka.dandamudi@intel.com, igt-dev@lists.freedesktop.org, arjun.melkaveri@intel.com, John Harrison , Jason Ekstrand List-ID: +Jason for this thoughts. On Fri, 22 Oct 2021 05:07:41 -0700, Tvrtko Ursulin wrote: > On 22/10/2021 05:40, Zbigniew Kempczy=F1ski wrote: > > On Thu, Oct 21, 2021 at 05:29:50PM -0700, Dixit, Ashutosh wrote: > >> On Thu, 21 Oct 2021 17:12:26 -0700, Dixit, Ashutosh wrote: > >>> > >>> On Thu, 21 Oct 2021 00:33:21 -0700, Zbigniew Kempczy=F1ski wrote: > >>>> > >>>> On Thu, Oct 21, 2021 at 10:05:07AM +0530, priyanka.dandamudi@intel.c= om wrote: > >>>>> From: Vinay Belgaumkar > >>>>> > >>>>> Add compute (CCS) engine. Add this to the IGT > >>>>> structure to allow gem tests to execute. > >>>>> > >>>>> Signed-off-by: Stuart Summers > >>>>> Signed-off-by: Vinay Belgaumkar > >>>>> Signed-off-by: Priyanka Dandamudi > >>>>> Cc: Ashutosh Dixit > >>>>> Cc: Arjun Melkaveri > >>>>> --- > >>>>> lib/igt_gt.c | 4 ++++ > >>>>> 1 file changed, 4 insertions(+) > >>>>> > >>>>> diff --git a/lib/igt_gt.c b/lib/igt_gt.c > >>>>> index a0ba04cc..80fb65ca 100644 > >>>>> --- a/lib/igt_gt.c > >>>>> +++ b/lib/igt_gt.c > >>>>> @@ -604,6 +604,10 @@ const struct intel_execution_engine2 intel_exe= cution_engines2[] =3D { > >>>>> { "vcs1", I915_ENGINE_CLASS_VIDEO, 1, I915_EXEC_BSD | I915_EXEC_BS= D_RING2 }, > >>>>> { "vcs2", I915_ENGINE_CLASS_VIDEO, 2, -1 }, > >>>>> { "vecs0", I915_ENGINE_CLASS_VIDEO_ENHANCE, 0, I915_EXEC_VEBOX }, > >>>>> + { "ccs0", I915_ENGINE_CLASS_COMPUTE, 0 , -1}, > >>>>> + { "ccs1", I915_ENGINE_CLASS_COMPUTE, 1 , -1}, > >>>>> + { "ccs2", I915_ENGINE_CLASS_COMPUTE, 2 , -1}, > >>>>> + { "ccs3", I915_ENGINE_CLASS_COMPUTE, 3 , -1}, > >>> > >>> Is this correct? Isn't intel_execution_engines2 a list of just the le= gacy > >>> engines? I don't think compute engines (which may vary in number) can= be > >>> added to the list of legacy engines. Isn't it true that compute engin= es can > >>> only be accessed by querying the present engines dynamically (using > >>> something like intel_ctx_create_all_physical())? > >> > >> I've copied Tvrtko (the boss :), but I am pretty sure what I said is > >> correct. Legacy engines are what context 0 is created with (without ad= ding > >> any more engines onto context 0). So unless we can confirm that these > >> engines are present for context 0 in the kernel we can't add them in I= GT. > > > > I'm sorry, you're right. I wasn't aware legacy engines are "frozen", so > > context 0 won't get an access to ccs. My r-b is incorrect then and patch > > shouldn't land. Another problem you've just realized me is with above > > patch I would still need to detect ccs somehow on context 0 depending > > on gen to allow iterator to go over existing engines. > > Don't know any longer guys - in the past "static engines" iterator was > supposed to be used to enumerate all possible engines _without_ querying > the device (like when enumerating subtests it isn't allowed to open the > device). > > As such CCS would go to intel_execution_engines2 with "-1" for flags, as > above patch had it. In other words in the past it was supposed to contain > all engines i915 engine query could possibly return. The array would then > also be used from elsewhere in the code to map class and instance to name > and similar. > > Whether or not all this changed in the intel_ctx_t rewrite I have no > idea. I see the "legacy" comment was added in: > > commit 9b32262bfadffffcde33c18ffb7c5292fbf4901e > Author: Jason Ekstrand > Date: Thu Apr 15 12:42:53 2021 -0500 > > docs: Add gem_engine_topology.h to the docs > > So perhaps ask Jason what was the plan there. > > Regards, > > Tvrtko