From patchwork Tue Mar 14 01:34:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: John Harrison X-Patchwork-Id: 13173524 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 52228C61DA4 for ; Tue, 14 Mar 2023 01:35:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A75AA10E6B7; Tue, 14 Mar 2023 01:35:41 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id ECA0F10E6B7 for ; Tue, 14 Mar 2023 01:35:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1678757738; x=1710293738; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=w140Ygo+/b1KucefR6tY1o1Z6Hx4OXphQ6AGCOSkUF0=; b=f2hkHG+gMGg1D0icXPE7bIBmCc+ODzupNUFz+Nb2kqZd+kT+SUgU2JK8 IXaYA/CRxi2jIwer0068HcVZB/BKBLgjctTdtq7np3aYrawZQaz2JF1Qq W4EnEwxkLXixf3K+J0klq1+wYitcjuKiJLpb/FcrCpbaESjq5nQfRfpKu ThYwJLhBtZLHL66/OXYFP68sFhWJPtrs+aJV9Hs6x0NEkgDdwmXFvY11E mIJXfammD7tUcHbWHRYb+89YrmQ/BkEJGAhJSoUFGqJKb6DYRiMxdWvuU KW68Pv3PTzLmR5Y6VacZcWOqGc9752JtYeL6UMpgaavkeXZNq2qNc6aCH A==; X-IronPort-AV: E=McAfee;i="6500,9779,10648"; a="423571345" X-IronPort-AV: E=Sophos;i="5.98,258,1673942400"; d="scan'208";a="423571345" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2023 18:35:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10648"; a="802660594" X-IronPort-AV: E=Sophos;i="5.98,258,1673942400"; d="scan'208";a="802660594" Received: from relo-linux-5.jf.intel.com ([10.165.21.152]) by orsmga004.jf.intel.com with ESMTP; 13 Mar 2023 18:35:38 -0700 From: John.C.Harrison@Intel.com To: stable@vger.kernel.org Date: Mon, 13 Mar 2023 18:34:41 -0700 Message-Id: <20230314013441.1245810-1-John.C.Harrison@Intel.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <167820544723615@kroah.com> References: <167820544723615@kroah.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 4.19.y] drm/i915: Don't use BAR mappings for ring buffers with LLC X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jani Nikula , intel-gfx@lists.freedesktop.org, Chris Wilson , Rodrigo Vivi Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" From: John Harrison Direction from hardware is that ring buffers should never be mapped via the BAR on systems with LLC. There are too many caching pitfalls due to the way BAR accesses are routed. So it is safest to just not use it. Signed-off-by: John Harrison Fixes: 9d80841ea4c9 ("drm/i915: Allow ringbuffers to be bound anywhere") Cc: Chris Wilson Cc: Joonas Lahtinen Cc: Jani Nikula Cc: Rodrigo Vivi Cc: Tvrtko Ursulin Cc: intel-gfx@lists.freedesktop.org Cc: # v4.9+ Tested-by: Jouni Högander Reviewed-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20230216011101.1909009-3-John.C.Harrison@Intel.com (cherry picked from commit 65c08339db1ada87afd6cfe7db8e60bb4851d919) Signed-off-by: Jani Nikula (cherry picked from commit 85636167e3206c3fbd52254fc432991cc4e90194) Signed-off-by: John Harrison --- drivers/gpu/drm/i915/intel_ringbuffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 3b8218dd9bb1..979d130b24c4 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1083,7 +1083,7 @@ int intel_ring_pin(struct intel_ring *ring, if (unlikely(ret)) return ret; - if (i915_vma_is_map_and_fenceable(vma)) + if (i915_vma_is_map_and_fenceable(vma) && !HAS_LLC(vma->vm->i915)) addr = (void __force *)i915_vma_pin_iomap(vma); else addr = i915_gem_object_pin_map(vma->obj, map); @@ -1118,7 +1118,7 @@ void intel_ring_unpin(struct intel_ring *ring) /* Discard any unused bytes beyond that submitted to hw. */ intel_ring_reset(ring, ring->tail); - if (i915_vma_is_map_and_fenceable(ring->vma)) + if (i915_vma_is_map_and_fenceable(ring->vma) && !HAS_LLC(ring->vma->vm->i915)) i915_vma_unpin_iomap(ring->vma); else i915_gem_object_unpin_map(ring->vma->obj);