From patchwork Wed Jan 19 21:06:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Brost X-Patchwork-Id: 12717783 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 B511EC433EF for ; Wed, 19 Jan 2022 21:14:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1F96410E5CA; Wed, 19 Jan 2022 21:14:40 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id D665710E425; Wed, 19 Jan 2022 21:14:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642626878; x=1674162878; h=from:to:subject:date:message-id:mime-version: content-transfer-encoding; bh=eoChbUb+MK9MnSv+RJPD37hp9TDVeWrkTrngH/4rGsw=; b=h4GKE8tPKMoI+ILvR+3AdHMBljUX3uE3EPIfDjP23pjMemOXbBtzQ694 p2rWrMgie+wOVrRAqcx4tIE2wThY9prCCIqU0vYUN3/S3OZOHKiV/W3xK jJXO+HiOVAQ8P+o3fBZYveiCIJe797x12kZBiQ+3S22E8yJvvt9yA7xK0 uAmoGwxgMXhVkbKlVPtGDeldHxdscLVvMEQ2vJfmQ2WeZLjIh+tARLnTf l7MlHUb0iwbu0M717lBRmSrOz2gP3V373JVAFsehR5Cl4U3FmCb1YGpIn p+WVzYW4h1sIl4rH7l36fa+6e66Z39IWDLWKOhKNktj9dK8tqj2YPvBsp g==; X-IronPort-AV: E=McAfee;i="6200,9189,10231"; a="331544617" X-IronPort-AV: E=Sophos;i="5.88,300,1635231600"; d="scan'208";a="331544617" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2022 13:12:36 -0800 X-IronPort-AV: E=Sophos;i="5.88,300,1635231600"; d="scan'208";a="693942121" Received: from jons-linux-dev-box.fm.intel.com ([10.1.27.20]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2022 13:12:27 -0800 From: Matthew Brost To: , Subject: [PATCH] drm/i915/guc: Ensure multi-lrc fini breadcrumb math is correct Date: Wed, 19 Jan 2022 13:06:39 -0800 Message-Id: <20220119210639.33053-1-matthew.brost@intel.com> X-Mailer: git-send-email 2.34.1 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" Realized that the GuC multi-lrc fini breadcrumb emit code is very delicate as the math this code does relies on functions it calls to emit a certain number of DWs. Add a few GEM_BUG_ONs to assert the math is correct. v2: - Rebase + resend for CI (Checkpatch) - Fix blank line warning Signed-off-by: Matthew Brost Reviewed-by: John Harrison --- .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 33 +++++++++++++++---- 1 file changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index 3918f1be114f..650efd3d3a48 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -4429,27 +4429,31 @@ static inline bool skip_handshake(struct i915_request *rq) return test_bit(I915_FENCE_FLAG_SKIP_PARALLEL, &rq->fence.flags); } +#define NON_SKIP_LEN 6 static u32 * emit_fini_breadcrumb_parent_no_preempt_mid_batch(struct i915_request *rq, u32 *cs) { struct intel_context *ce = rq->context; + __maybe_unused u32 *before_fini_breadcrumb_user_interrupt_cs; + __maybe_unused u32 *start_fini_breadcrumb_cs = cs; GEM_BUG_ON(!intel_context_is_parent(ce)); if (unlikely(skip_handshake(rq))) { /* * NOP everything in __emit_fini_breadcrumb_parent_no_preempt_mid_batch, - * the -6 comes from the length of the emits below. + * the NON_SKIP_LEN comes from the length of the emits below. */ memset(cs, 0, sizeof(u32) * - (ce->engine->emit_fini_breadcrumb_dw - 6)); - cs += ce->engine->emit_fini_breadcrumb_dw - 6; + (ce->engine->emit_fini_breadcrumb_dw - NON_SKIP_LEN)); + cs += ce->engine->emit_fini_breadcrumb_dw - NON_SKIP_LEN; } else { cs = __emit_fini_breadcrumb_parent_no_preempt_mid_batch(rq, cs); } /* Emit fini breadcrumb */ + before_fini_breadcrumb_user_interrupt_cs = cs; cs = gen8_emit_ggtt_write(cs, rq->fence.seqno, i915_request_active_timeline(rq)->hwsp_offset, @@ -4459,6 +4463,12 @@ emit_fini_breadcrumb_parent_no_preempt_mid_batch(struct i915_request *rq, *cs++ = MI_USER_INTERRUPT; *cs++ = MI_NOOP; + /* Ensure our math for skip + emit is correct */ + GEM_BUG_ON(before_fini_breadcrumb_user_interrupt_cs + NON_SKIP_LEN != + cs); + GEM_BUG_ON(start_fini_breadcrumb_cs + + ce->engine->emit_fini_breadcrumb_dw != cs); + rq->tail = intel_ring_offset(rq, cs); return cs; @@ -4501,22 +4511,25 @@ emit_fini_breadcrumb_child_no_preempt_mid_batch(struct i915_request *rq, u32 *cs) { struct intel_context *ce = rq->context; + __maybe_unused u32 *before_fini_breadcrumb_user_interrupt_cs; + __maybe_unused u32 *start_fini_breadcrumb_cs = cs; GEM_BUG_ON(!intel_context_is_child(ce)); if (unlikely(skip_handshake(rq))) { /* * NOP everything in __emit_fini_breadcrumb_child_no_preempt_mid_batch, - * the -6 comes from the length of the emits below. + * the NON_SKIP_LEN comes from the length of the emits below. */ memset(cs, 0, sizeof(u32) * - (ce->engine->emit_fini_breadcrumb_dw - 6)); - cs += ce->engine->emit_fini_breadcrumb_dw - 6; + (ce->engine->emit_fini_breadcrumb_dw - NON_SKIP_LEN)); + cs += ce->engine->emit_fini_breadcrumb_dw - NON_SKIP_LEN; } else { cs = __emit_fini_breadcrumb_child_no_preempt_mid_batch(rq, cs); } /* Emit fini breadcrumb */ + before_fini_breadcrumb_user_interrupt_cs = cs; cs = gen8_emit_ggtt_write(cs, rq->fence.seqno, i915_request_active_timeline(rq)->hwsp_offset, @@ -4526,11 +4539,19 @@ emit_fini_breadcrumb_child_no_preempt_mid_batch(struct i915_request *rq, *cs++ = MI_USER_INTERRUPT; *cs++ = MI_NOOP; + /* Ensure our math for skip + emit is correct */ + GEM_BUG_ON(before_fini_breadcrumb_user_interrupt_cs + NON_SKIP_LEN != + cs); + GEM_BUG_ON(start_fini_breadcrumb_cs + + ce->engine->emit_fini_breadcrumb_dw != cs); + rq->tail = intel_ring_offset(rq, cs); return cs; } +#undef NON_SKIP_LEN + static struct intel_context * guc_create_virtual(struct intel_engine_cs **siblings, unsigned int count, unsigned long flags)