From patchwork Wed Oct 13 20:42:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Brost X-Patchwork-Id: 12557249 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45765C433F5 for ; Wed, 13 Oct 2021 20:56:36 +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 1883261152 for ; Wed, 13 Oct 2021 20:56:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1883261152 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C15896EB85; Wed, 13 Oct 2021 20:56:03 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 209EF6EB6F; Wed, 13 Oct 2021 20:55:58 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10136"; a="214690379" X-IronPort-AV: E=Sophos;i="5.85,371,1624345200"; d="scan'208";a="214690379" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2021 13:47:20 -0700 X-IronPort-AV: E=Sophos;i="5.85,371,1624345200"; d="scan'208";a="524782708" Received: from jons-linux-dev-box.fm.intel.com ([10.1.27.20]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2021 13:47:19 -0700 From: Matthew Brost To: , Cc: Subject: [PATCH 07/25] drm/i915/guc: Introduce context parent-child relationship Date: Wed, 13 Oct 2021 13:42:13 -0700 Message-Id: <20211013204231.19287-8-matthew.brost@intel.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211013204231.19287-1-matthew.brost@intel.com> References: <20211013204231.19287-1-matthew.brost@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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Introduce context parent-child relationship. Once this relationship is created all pinning / unpinning operations are directed to the parent context. The parent context is responsible for pinning all of its children and itself. This is a precursor to the full GuC multi-lrc implementation but aligns to how GuC mutli-lrc interface is defined - a single H2G is used register / deregister all of the contexts simultaneously. Subsequent patches in the series will implement the pinning / unpinning operations for parent / child contexts. v2: (Daniel Vetter) - Add kernel doc, add wrapper to access parent to ensure safety v3: (John Harrison) - Fix comment explaing GEM_BUG_ON in to_parent() - Make variable names generic (non-GuC specific) v4: (John Harrison) - s/its'/its/g Signed-off-by: Matthew Brost Reviewed-by: John Harrison --- drivers/gpu/drm/i915/gt/intel_context.c | 29 +++++++++++++ drivers/gpu/drm/i915/gt/intel_context.h | 41 +++++++++++++++++++ drivers/gpu/drm/i915/gt/intel_context_types.h | 21 ++++++++++ 3 files changed, 91 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index f98c9f470ba1..79f321c6c008 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -404,6 +404,8 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) INIT_LIST_HEAD(&ce->destroyed_link); + INIT_LIST_HEAD(&ce->parallel.child_list); + /* * Initialize fence to be complete as this is expected to be complete * unless there is a pending schedule disable outstanding. @@ -418,10 +420,17 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) void intel_context_fini(struct intel_context *ce) { + struct intel_context *child, *next; + if (ce->timeline) intel_timeline_put(ce->timeline); i915_vm_put(ce->vm); + /* Need to put the creation ref for the children */ + if (intel_context_is_parent(ce)) + for_each_child_safe(ce, child, next) + intel_context_put(child); + mutex_destroy(&ce->pin_mutex); i915_active_fini(&ce->active); i915_sw_fence_fini(&ce->guc_state.blocked); @@ -538,6 +547,26 @@ struct i915_request *intel_context_find_active_request(struct intel_context *ce) return active; } +void intel_context_bind_parent_child(struct intel_context *parent, + struct intel_context *child) +{ + /* + * Callers responsibility to validate that this function is used + * correctly but we use GEM_BUG_ON here ensure that they do. + */ + GEM_BUG_ON(!intel_engine_uses_guc(parent->engine)); + GEM_BUG_ON(intel_context_is_pinned(parent)); + GEM_BUG_ON(intel_context_is_child(parent)); + GEM_BUG_ON(intel_context_is_pinned(child)); + GEM_BUG_ON(intel_context_is_child(child)); + GEM_BUG_ON(intel_context_is_parent(child)); + + parent->parallel.number_children++; + list_add_tail(&child->parallel.child_link, + &parent->parallel.child_list); + child->parallel.parent = parent; +} + #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftest_context.c" #endif diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h index c41098950746..b63c10a144af 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.h +++ b/drivers/gpu/drm/i915/gt/intel_context.h @@ -44,6 +44,47 @@ void intel_context_free(struct intel_context *ce); int intel_context_reconfigure_sseu(struct intel_context *ce, const struct intel_sseu sseu); +static inline bool intel_context_is_child(struct intel_context *ce) +{ + return !!ce->parallel.parent; +} + +static inline bool intel_context_is_parent(struct intel_context *ce) +{ + return !!ce->parallel.number_children; +} + +static inline bool intel_context_is_pinned(struct intel_context *ce); + +static inline struct intel_context * +intel_context_to_parent(struct intel_context *ce) +{ + if (intel_context_is_child(ce)) { + /* + * The parent holds ref count to the child so it is always safe + * for the parent to access the child, but the child has a + * pointer to the parent without a ref. To ensure this is safe + * the child should only access the parent pointer while the + * parent is pinned. + */ + GEM_BUG_ON(!intel_context_is_pinned(ce->parallel.parent)); + + return ce->parallel.parent; + } else { + return ce; + } +} + +void intel_context_bind_parent_child(struct intel_context *parent, + struct intel_context *child); + +#define for_each_child(parent, ce)\ + list_for_each_entry(ce, &(parent)->parallel.child_list,\ + parallel.child_link) +#define for_each_child_safe(parent, ce, cn)\ + list_for_each_entry_safe(ce, cn, &(parent)->parallel.child_list,\ + parallel.child_link) + /** * intel_context_lock_pinned - Stablises the 'pinned' status of the HW context * @ce - the context diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index 4613d027cbc3..76dfca57cb45 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -220,6 +220,27 @@ struct intel_context { */ struct list_head destroyed_link; + /** @parallel: sub-structure for parallel submission members */ + struct { + union { + /** + * @child_list: parent's list of children + * contexts, no protection as immutable after context + * creation + */ + struct list_head child_list; + /** + * @child_link: child's link into parent's list of + * children + */ + struct list_head child_link; + }; + /** @parent: pointer to parent if child */ + struct intel_context *parent; + /** @number_children: number of children if parent */ + u8 number_children; + } parallel; + #ifdef CONFIG_DRM_I915_SELFTEST /** * @drop_schedule_enable: Force drop of schedule enable G2H for selftest