From patchwork Fri Feb 11 11:34:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Matthew Auld X-Patchwork-Id: 12743261 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 1BD1EC433F5 for ; Fri, 11 Feb 2022 11:35:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 144A410EABE; Fri, 11 Feb 2022 11:35:22 +0000 (UTC) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id B049110EAC8; Fri, 11 Feb 2022 11:35:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644579306; x=1676115306; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=5x8O5nyFe6o3RM+g6LPzeCSeiAaT3q+u3wcxwb9Sjr8=; b=MQxdbA+/lV/gdHju3fHT0Rf+CMhQLHgU32edJduVTA72E0CbExNWIThO qllx1xLOw4wTq3R9QzXG4TN6VnKMrnpwyG2PDcVPxS4SvogvUxQO872yy nX1yv3V7oll4JBHgSl2yNqZHj4xvM2diLc9tI3OWfCG9tRkfj79sMJD5G Xt/fhPkYKajEn9+U8K3VkB5rEMoK1k+iAfPr99hBkRhCHNBRxCN26lBeX uy1BM59H7PqqtxiFMRFWjQw1LM0Vmf88D3xlJhHmyq3Xh64RNxt54KCoj ToWihY3HChUlt/C3sW7RYJxv8RRIN5FYme2osL8o4I3Ts7rVMAnXUDaXL g==; X-IronPort-AV: E=McAfee;i="6200,9189,10254"; a="248548262" X-IronPort-AV: E=Sophos;i="5.88,360,1635231600"; d="scan'208";a="248548262" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Feb 2022 03:35:06 -0800 X-IronPort-AV: E=Sophos;i="5.88,360,1635231600"; d="scan'208";a="602355024" Received: from pogara-mobl1.ger.corp.intel.com (HELO mwauld-desk1.intel.com) ([10.252.19.40]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Feb 2022 03:35:05 -0800 From: Matthew Auld To: intel-gfx@lists.freedesktop.org Subject: [PATCH v3 13/15] drm/i915/uapi: add NEEDS_CPU_ACCESS hint Date: Fri, 11 Feb 2022 11:34:35 +0000 Message-Id: <20220211113437.874691-14-matthew.auld@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220211113437.874691-1-matthew.auld@intel.com> References: <20220211113437.874691-1-matthew.auld@intel.com> MIME-Version: 1.0 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: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Jon Bloomfield , dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If set, force the allocation to be placed in the mappable portion of LMEM. One big restriction here is that system memory must be given as a potential placement for the object, that way we can always spill the object into system memory if we can't make space. XXX: Still needs IGTs. Including now just for the sake of having more complete picture. Signed-off-by: Matthew Auld Cc: Thomas Hellström Cc: Jon Bloomfield --- drivers/gpu/drm/i915/gem/i915_gem_create.c | 26 ++++++++++++------ include/uapi/drm/i915_drm.h | 31 +++++++++++++++++++++- 2 files changed, 48 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_create.c b/drivers/gpu/drm/i915/gem/i915_gem_create.c index ecb8c2feec46..6d4a637ec654 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_create.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_create.c @@ -238,6 +238,7 @@ struct create_ext { struct drm_i915_private *i915; struct intel_memory_region *placements[INTEL_REGION_UNKNOWN]; unsigned int n_placements; + unsigned int placement_mask; unsigned long flags; }; @@ -334,6 +335,7 @@ static int set_placements(struct drm_i915_gem_create_ext_memory_regions *args, for (i = 0; i < args->num_regions; i++) ext_data->placements[i] = placements[i]; + ext_data->placement_mask = mask; return 0; out_dump: @@ -408,7 +410,7 @@ i915_gem_create_ext_ioctl(struct drm_device *dev, void *data, struct drm_i915_gem_object *obj; int ret; - if (args->flags) + if (args->flags & ~I915_GEM_CREATE_EXT_FLAG_NEEDS_CPU_ACCESS) return -EINVAL; ret = i915_user_extensions(u64_to_user_ptr(args->extensions), @@ -424,13 +426,21 @@ i915_gem_create_ext_ioctl(struct drm_device *dev, void *data, ext_data.n_placements = 1; } - /* - * TODO: add a userspace hint to force CPU_ACCESS for the object, which - * can override this. - */ - if (ext_data.n_placements > 1 || - ext_data.placements[0]->type != INTEL_MEMORY_SYSTEM) - ext_data.flags |= I915_BO_ALLOC_GPU_ONLY; + if (args->flags & I915_GEM_CREATE_EXT_FLAG_NEEDS_CPU_ACCESS) { + if (ext_data.n_placements == 1) + return -EINVAL; + + /* + * We always need to be able to spill to system memory, if we + * can't place in the mappable part of LMEM. + */ + if (!(ext_data.placement_mask & BIT(INTEL_REGION_SMEM))) + return -EINVAL; + } else { + if (ext_data.n_placements > 1 || + ext_data.placements[0]->type != INTEL_MEMORY_SYSTEM) + ext_data.flags |= I915_BO_ALLOC_GPU_ONLY; + } obj = __i915_gem_object_create_user_ext(i915, args->size, ext_data.placements, diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index 914ebd9290e5..925685bd261e 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -3157,7 +3157,36 @@ struct drm_i915_gem_create_ext { * Object handles are nonzero. */ __u32 handle; - /** @flags: MBZ */ + /** + * @flags: Optional flags. + * + * Supported values: + * + * I915_GEM_CREATE_EXT_FLAG_NEEDS_CPU_ACCESS - Signal to the kernel that + * the object will need to be accessed via the CPU. + * + * Only valid when placing objects in I915_MEMORY_CLASS_DEVICE, and + * only strictly required on platforms where only some of the device + * memory is directly visible or mappable through the CPU, like on DG2+. + * + * One of the placements MUST also be I915_MEMORY_CLASS_SYSTEM, to + * ensure we can always spill the allocation to system memory, if we + * can't place the object in the mappable part of + * I915_MEMORY_CLASS_DEVICE. + * + * Note that buffers that need to be captured with EXEC_OBJECT_CAPTURE, + * will need to enable this hint, if the object can also be placed in + * I915_MEMORY_CLASS_DEVICE, starting from DG2+. The execbuf call will + * throw an error otherwise. This also means that such objects will need + * I915_MEMORY_CLASS_SYSTEM set as a possible placement. + * + * Without this hint, the kernel will assume that non-mappable + * I915_MEMORY_CLASS_DEVICE is preferred for this object. Note that the + * kernel can still migrate the object to the mappable part, as a last + * resort, if userspace ever CPU faults this object, but this might be + * expensive, and so ideally should be avoided. + */ +#define I915_GEM_CREATE_EXT_FLAG_NEEDS_CPU_ACCESS (1 << 0) __u32 flags; /** * @extensions: The chain of extensions to apply to this object.