From patchwork Wed Jan 26 15:21:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Matthew Auld X-Patchwork-Id: 12725280 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 AC908C63684 for ; Wed, 26 Jan 2022 15:23:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BA37610E95F; Wed, 26 Jan 2022 15:22:33 +0000 (UTC) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id BC15E10E900; Wed, 26 Jan 2022 15:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643210546; x=1674746546; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=SejTynlJSjOKBO36cj56rGbbcEZAlBryD85kVp98RdM=; b=kskiXCQe3hrJsZ4bm9074gvk/ULiyMmjWHlKQlE/ch+VrI3l+xHkJ6Lk w5cFmWDfAMRUKn4Op3b3vRdYUOsOctTjOs+7Hsh8TSNpylQfMHeEpPI4s UB8n8JkeNf00QYD60IUAI98ewtz22A8uJR+se9DHYiqOpBLoLHlHpR9mK B4UqhhNmPN+l0kKtddU7c4/05HMVoDePm/nL4Y8kv2WE9q09oG1vlbV+R BjJ5btKSDim5ncc0FPPlZbBsma/i67BUoRcZeJGpFTryB8ofHcXwJChM9 jgakv+dDGz3QMPLE/afbrdFSLOFkb9yDhKu0BJDoQ/3PuNDmAPRHUPWzn Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10238"; a="309885282" X-IronPort-AV: E=Sophos;i="5.88,318,1635231600"; d="scan'208";a="309885282" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jan 2022 07:22:26 -0800 X-IronPort-AV: E=Sophos;i="5.88,318,1635231600"; d="scan'208";a="674386318" Received: from jamesstx-mobl.ger.corp.intel.com (HELO mwauld-desk1.intel.com) ([10.213.247.182]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jan 2022 07:22:25 -0800 From: Matthew Auld To: intel-gfx@lists.freedesktop.org Subject: [PATCH 17/20] drm/i915/uapi: add NEEDS_CPU_ACCESS hint Date: Wed, 26 Jan 2022 15:21:52 +0000 Message-Id: <20220126152155.3070602-18-matthew.auld@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220126152155.3070602-1-matthew.auld@intel.com> References: <20220126152155.3070602-1-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?= , 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 very much WIP and needs IGTs. Including now just for the sake of having more complete picture. Signed-off-by: Matthew Auld Cc: Thomas Hellström --- drivers/gpu/drm/i915/gem/i915_gem_create.c | 28 ++++++++++++------- include/uapi/drm/i915_drm.h | 31 +++++++++++++++++++++- 2 files changed, 49 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_create.c b/drivers/gpu/drm/i915/gem/i915_gem_create.c index e7456443f163..98d63cb21e94 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), @@ -424,14 +426,22 @@ 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 (!IS_DG1(i915) && (ext_data.n_placements > 1 || - ext_data.placements[0]->type != - INTEL_MEMORY_SYSTEM)) - ext_data.flags |= I915_BO_ALLOC_TOPDOWN; + 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 (!IS_DG1(i915) && (ext_data.n_placements > 1 || + ext_data.placements[0]->type != + INTEL_MEMORY_SYSTEM)) + ext_data.flags |= I915_BO_ALLOC_TOPDOWN; + } 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..ecfa805549a7 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.