From patchwork Fri Dec 3 23:51:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Brost X-Patchwork-Id: 12656091 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 2D2D7C433F5 for ; Fri, 3 Dec 2021 23:56:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7D1B2AB620; Fri, 3 Dec 2021 23:56:44 +0000 (UTC) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id AF324AB620; Fri, 3 Dec 2021 23:56:43 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10187"; a="237016981" X-IronPort-AV: E=Sophos;i="5.87,284,1631602800"; d="scan'208";a="237016981" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Dec 2021 15:56:43 -0800 X-IronPort-AV: E=Sophos;i="5.87,284,1631602800"; d="scan'208";a="678282784" 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; 03 Dec 2021 15:56:43 -0800 From: Matthew Brost To: Date: Fri, 3 Dec 2021 15:51:12 -0800 Message-Id: <20211203235112.3358-1-matthew.brost@intel.com> X-Mailer: git-send-email 2.33.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915: Rollback seqno when request creation fails 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: dri-devel@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" gem_ctx_create.basic-files can slam on kernel contexts to the extent where request creation fails because the ring is full. When this happens seqno numbers are skipped which can result the below GEM_BUG_ON blowing in gt/intel_engine_pm.c:__engine_unpark: GEM_BUG_ON(ce->timeline->seqno != READ_ONCE(*ce->timeline->hwsp_seqno)); Fixup request creation code to roll back seqno when request creation fails. v2: (CI) - Fix build error Signed-off-by: Matthew Brost --- drivers/gpu/drm/i915/gt/intel_timeline.c | 8 ++++++++ drivers/gpu/drm/i915/gt/intel_timeline.h | 1 + drivers/gpu/drm/i915/i915_request.c | 1 + 3 files changed, 10 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c index 438bbc7b8147..3785e5605549 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.c +++ b/drivers/gpu/drm/i915/gt/intel_timeline.c @@ -301,6 +301,14 @@ static u32 timeline_advance(struct intel_timeline *tl) return tl->seqno += 1 + tl->has_initial_breadcrumb; } +void intel_timeline_rollback_seqno(struct intel_timeline *tl) +{ + GEM_BUG_ON(!atomic_read(&tl->pin_count)); + GEM_BUG_ON(tl->seqno & tl->has_initial_breadcrumb); + + tl->seqno -= 1 + tl->has_initial_breadcrumb; +} + static noinline int __intel_timeline_get_seqno(struct intel_timeline *tl, u32 *seqno) diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.h b/drivers/gpu/drm/i915/gt/intel_timeline.h index 57308c4d664a..a2f2e0ea186f 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.h +++ b/drivers/gpu/drm/i915/gt/intel_timeline.h @@ -72,6 +72,7 @@ void intel_timeline_enter(struct intel_timeline *tl); int intel_timeline_get_seqno(struct intel_timeline *tl, struct i915_request *rq, u32 *seqno); +void intel_timeline_rollback_seqno(struct intel_timeline *tl); void intel_timeline_exit(struct intel_timeline *tl); void intel_timeline_unpin(struct intel_timeline *tl); diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index a72c8f0346a0..86f32ee082f7 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -966,6 +966,7 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp) err_unwind: ce->ring->emit = rq->head; + intel_timeline_rollback_seqno(tl); /* Make sure we didn't add ourselves to external state before freeing */ GEM_BUG_ON(!list_empty(&rq->sched.signalers_list));