From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E304BC432BE for ; Fri, 20 Aug 2021 00:03:42 +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 A5C9B60E78 for ; Fri, 20 Aug 2021 00:03:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A5C9B60E78 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 E9E336E9ED; Fri, 20 Aug 2021 00:03:40 +0000 (UTC) Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by gabe.freedesktop.org (Postfix) with ESMTPS id 041FE6E9EC; Fri, 20 Aug 2021 00:03:38 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10081"; a="203828000" X-IronPort-AV: E=Sophos;i="5.84,336,1620716400"; d="scan'208";a="203828000" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2021 17:03:38 -0700 X-IronPort-AV: E=Sophos;i="5.84,336,1620716400"; d="scan'208";a="512316873" Received: from jons-linux-dev-box.fm.intel.com (HELO jons-linux-dev-box) ([10.1.27.20]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2021 17:03:38 -0700 Date: Thu, 19 Aug 2021 16:58:25 -0700 From: Matthew Brost To: Daniele Ceraolo Spurio Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, daniel.vetter@ffwll.ch Message-ID: <20210819235825.GA16207@jons-linux-dev-box> References: <20210819061639.21051-1-matthew.brost@intel.com> <20210819061639.21051-5-matthew.brost@intel.com> <274c1930-db30-bacc-8b61-db439f8ec19c@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <274c1930-db30-bacc-8b61-db439f8ec19c@intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Subject: Re: [Intel-gfx] [PATCH 04/27] drm/i915/guc: Don't drop ce->guc_active.lock when unwinding context 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Thu, Aug 19, 2021 at 05:01:03PM -0700, Daniele Ceraolo Spurio wrote: > > > On 8/18/2021 11:16 PM, Matthew Brost wrote: > > Don't drop ce->guc_active.lock when unwinding a context after reset. > > At one point we had to drop this because of a lock inversion but that is > > no longer the case. It is much safer to hold the lock so let's do that. > > > > Fixes: eb5e7da736f3 ("drm/i915/guc: Reset implementation for new GuC interface") > > Signed-off-by: Matthew Brost > > Cc: > > Reviewed-by: Daniele Ceraolo Spurio > > Do we have a trybot of this series with GuC enabled? I've checked the > functions called in the previously unlocked chunk and didn't spot anything > requiring the lock to be dropped, but I'd feel safer if we had lockdep > results as well. > RKL uses GuC submission with BAT. This has been thoroughly tested by me too and no lockdep splats. Can kick off a trybot on the next rev of this series too. Matt > Daniele > > > --- > > drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 4 ---- > > 1 file changed, 4 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 9ca0ba4ea85a..e4a099f8f820 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > @@ -812,8 +812,6 @@ __unwind_incomplete_requests(struct intel_context *ce) > > continue; > > list_del_init(&rq->sched.link); > > - spin_unlock(&ce->guc_active.lock); > > - > > __i915_request_unsubmit(rq); > > /* Push the request back into the queue for later resubmission. */ > > @@ -826,8 +824,6 @@ __unwind_incomplete_requests(struct intel_context *ce) > > list_add(&rq->sched.link, pl); > > set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); > > - > > - spin_lock(&ce->guc_active.lock); > > } > > spin_unlock(&ce->guc_active.lock); > > spin_unlock_irqrestore(&sched_engine->lock, flags); >