From nobody Mon Feb 9 16:47:08 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B72DC761A6 for ; Fri, 31 Mar 2023 14:16:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230162AbjCaOQ5 (ORCPT ); Fri, 31 Mar 2023 10:16:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43554 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229850AbjCaOQy (ORCPT ); Fri, 31 Mar 2023 10:16:54 -0400 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21E6819A0 for ; Fri, 31 Mar 2023 07:16:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680272213; x=1711808213; h=from:date:subject:mime-version:content-transfer-encoding: message-id:to:cc; 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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20230330-hold_wakeref_for_active_vm-v2-1-724d201499c2@intel.com> X-B4-Tracking: v=1; b=H4sIAETrJmQC/42OSw6DIBRFt2IYl4aP0dhR99EYgvgoL1UxQGgb4 96LrqDDc2/uZyMRAkIkt2ojATJG9EsBcamIcXp5AsWxMBFMSCYlo85Po3rrFwSwyvqgtEmYQeWZ tpZxqeu6AytJKRh0BDoEvRh3VIxhpgnXw1lLGD/n7KMv7DAmH77ni8wP9a/BzCmngza65aLphG3 uuCSYrsbPpN/3/QdPBHkC3gAAAA== To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Chris Wilson , Andi Shyti , Chris Wilson , Andrzej Hajda X-Mailer: b4 0.11.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chris Wilson There may be a disconnect between the GT used by the engine and the GT used for the VM, requiring us to hold a wakeref on both while the GPU is active with this request. v2: added explanation to __queue_and_release_pm Signed-off-by: Chris Wilson [ahajda: removed not-yet-upstremed wakeref tracking bits] Signed-off-by: Andrzej Hajda Reviewed-by: Andi Shyti =20 Reviewed-by: Tvrtko Ursulin --- Changes in v2: - Link to v1: https://lore.kernel.org/r/20230330-hold_wakeref_for_active_vm= -v1-1-baca712692f6@intel.com --- drivers/gpu/drm/i915/gt/intel_context.h | 15 +++++++++++---- drivers/gpu/drm/i915/gt/intel_engine_pm.c | 9 +++++++++ 2 files changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915= /gt/intel_context.h index 0a8d553da3f439..48f888c3da083b 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.h +++ b/drivers/gpu/drm/i915/gt/intel_context.h @@ -14,6 +14,7 @@ #include "i915_drv.h" #include "intel_context_types.h" #include "intel_engine_types.h" +#include "intel_gt_pm.h" #include "intel_ring_types.h" #include "intel_timeline_types.h" #include "i915_trace.h" @@ -207,8 +208,11 @@ void intel_context_exit_engine(struct intel_context *c= e); static inline void intel_context_enter(struct intel_context *ce) { lockdep_assert_held(&ce->timeline->mutex); - if (!ce->active_count++) - ce->ops->enter(ce); + if (ce->active_count++) + return; + + ce->ops->enter(ce); + intel_gt_pm_get(ce->vm->gt); } =20 static inline void intel_context_mark_active(struct intel_context *ce) @@ -222,8 +226,11 @@ static inline void intel_context_exit(struct intel_con= text *ce) { lockdep_assert_held(&ce->timeline->mutex); GEM_BUG_ON(!ce->active_count); - if (!--ce->active_count) - ce->ops->exit(ce); + if (--ce->active_count) + return; + + intel_gt_pm_put_async(ce->vm->gt); + ce->ops->exit(ce); } =20 static inline struct intel_context *intel_context_get(struct intel_context= *ce) diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i9= 15/gt/intel_engine_pm.c index e971b153fda976..ee531a5c142c77 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c @@ -114,6 +114,15 @@ __queue_and_release_pm(struct i915_request *rq, =20 ENGINE_TRACE(engine, "parking\n"); =20 + /* + * Open coded one half of intel_context_enter, which we have to omit + * here (see the large comment below) and because the other part must + * not be called due constructing directly with __i915_request_create + * which increments active count via intel_context_mark_active. + */ + GEM_BUG_ON(rq->context->active_count !=3D 1); + __intel_gt_pm_get(engine->gt); + /* * We have to serialise all potential retirement paths with our * submission, as we don't want to underflow either the --- base-commit: 3385d6482cd60f2a0bbb0fa97b70ae7dbba4f95c change-id: 20230330-hold_wakeref_for_active_vm-7f013a449ef3 Best regards, --=20 Andrzej Hajda