From patchwork Thu Jan 7 22:17:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 12004993 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 49C0FC433E6 for ; Thu, 7 Jan 2021 22:17:38 +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 9BA67235FD for ; Thu, 7 Jan 2021 22:17:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9BA67235FD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1B1246E550; Thu, 7 Jan 2021 22:17:37 +0000 (UTC) Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id DD04B6E550 for ; Thu, 7 Jan 2021 22:17:35 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 23532723-1500050 for multiple; Thu, 07 Jan 2021 22:17:26 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 7 Jan 2021 22:17:21 +0000 Message-Id: <20210107221724.10036-2-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210107221724.10036-1-chris@chris-wilson.co.uk> References: <20210107221724.10036-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 2/5] drm/i915/gt: Restore ce->signal flush before releasing virtual engine 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: Chris Wilson Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Before we mark the virtual engine as no longer inflight, flush any ongoing signaling that may be using the ce->signal_link along the previous breadcrumbs. On switch to a new physical engine, that link will be inserted into the new set of breadcrumbs, causing confusion to an ongoing iterator. This patch undoes a last minute mistake introduced into commit bab0557c8dca ("drm/i915/gt: Remove virtual breadcrumb before transfer"), whereby instead of unconditionally applying the flush, it was only applied if the request itself was going to be reused. v2: Generalise and cancel all remaining ce->signals Fixes: bab0557c8dca ("drm/i915/gt: Remove virtual breadcrumb before transfer") Signed-off-by: Chris Wilson Reviewed-by: Andi Shyti --- drivers/gpu/drm/i915/gt/intel_breadcrumbs.c | 33 +++++++++++++++++++ drivers/gpu/drm/i915/gt/intel_breadcrumbs.h | 4 +++ .../drm/i915/gt/intel_execlists_submission.c | 25 ++++++-------- 3 files changed, 47 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c index 2eabb9ab5d47..7137b6f24f55 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c @@ -472,6 +472,39 @@ void i915_request_cancel_breadcrumb(struct i915_request *rq) i915_request_put(rq); } +void intel_context_remove_breadcrumbs(struct intel_context *ce, + struct intel_breadcrumbs *b) +{ + struct i915_request *rq, *rn; + bool release = false; + unsigned long flags; + + spin_lock_irqsave(&ce->signal_lock, flags); + + if (list_empty(&ce->signals)) + goto unlock; + + list_for_each_entry_safe(rq, rn, &ce->signals, signal_link) { + GEM_BUG_ON(!__i915_request_is_complete(rq)); + if (!test_and_clear_bit(I915_FENCE_FLAG_SIGNAL, + &rq->fence.flags)) + continue; + + list_del_rcu(&rq->signal_link); + irq_signal_request(rq, b); + i915_request_put(rq); + } + release = remove_signaling_context(b, ce); + +unlock: + spin_unlock_irqrestore(&ce->signal_lock, flags); + if (release) + intel_context_put(ce); + + while (atomic_read(&b->signaler_active)) + cpu_relax(); +} + static void print_signals(struct intel_breadcrumbs *b, struct drm_printer *p) { struct intel_context *ce; diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h index 75cc9cff3ae3..3ce5ce270b04 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h @@ -6,6 +6,7 @@ #ifndef __INTEL_BREADCRUMBS__ #define __INTEL_BREADCRUMBS__ +#include #include #include "intel_engine_types.h" @@ -44,4 +45,7 @@ void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine, bool i915_request_enable_breadcrumb(struct i915_request *request); void i915_request_cancel_breadcrumb(struct i915_request *request); +void intel_context_remove_breadcrumbs(struct intel_context *ce, + struct intel_breadcrumbs *b); + #endif /* __INTEL_BREADCRUMBS__ */ diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c index 2f8e10450f7e..eb69eef9d7db 100644 --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -581,21 +581,6 @@ resubmit_virtual_request(struct i915_request *rq, struct virtual_engine *ve) { struct intel_engine_cs *engine = rq->engine; - /* Flush concurrent rcu iterators in signal_irq_work */ - if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &rq->fence.flags)) { - /* - * After this point, the rq may be transferred to a new - * sibling, so before we clear ce->inflight make sure that - * the context has been removed from the b->signalers and - * furthermore we need to make sure that the concurrent - * iterator in signal_irq_work is no longer following - * ce->signal_link. - */ - i915_request_cancel_breadcrumb(rq); - while (atomic_read(&engine->breadcrumbs->signaler_active)) - cpu_relax(); - } - spin_lock_irq(&engine->active.lock); clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); @@ -610,6 +595,16 @@ static void kick_siblings(struct i915_request *rq, struct intel_context *ce) struct virtual_engine *ve = container_of(ce, typeof(*ve), context); struct intel_engine_cs *engine = rq->engine; + /* + * After this point, the rq may be transferred to a new sibling, so + * before we clear ce->inflight make sure that the context has been + * removed from the b->signalers and furthermore we need to make sure + * that the concurrent iterator in signal_irq_work is no longer + * following ce->signal_link. + */ + if (!list_empty(&ce->signals)) + intel_context_remove_breadcrumbs(ce, engine->breadcrumbs); + /* * This engine is now too busy to run this virtual request, so * see if we can find an alternative engine for it to execute on.