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=-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,URIBL_BLOCKED,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 005EFC433E0 for ; Mon, 25 Jan 2021 14:02:51 +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 9DDA0230FD for ; Mon, 25 Jan 2021 14:02:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9DDA0230FD 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 5B9E26E1BE; Mon, 25 Jan 2021 14:02:38 +0000 (UTC) Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7D77A6E156 for ; Mon, 25 Jan 2021 14:02:01 +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 23693637-1500050 for multiple; Mon, 25 Jan 2021 14:01:38 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Mon, 25 Jan 2021 14:01:10 +0000 Message-Id: <20210125140136.10494-15-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210125140136.10494-1-chris@chris-wilson.co.uk> References: <20210125140136.10494-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 15/41] drm/i915: Fix the iterative dfs for defering requests 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: thomas.hellstrom@intel.com, Chris Wilson Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" The current implementation of walking the children of a deferred requests lacks the backtracking required to reduce the dfs to linear. Having pulled it from execlists into the common layer, we can reuse the dfs code for priority inheritance. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_scheduler.c | 58 +++++++++++++++++++-------- 1 file changed, 42 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c index 4d648c2d603a..7c93c2a8309b 100644 --- a/drivers/gpu/drm/i915/i915_scheduler.c +++ b/drivers/gpu/drm/i915/i915_scheduler.c @@ -454,25 +454,26 @@ void i915_request_set_priority(struct i915_request *rq, int prio) void __intel_engine_defer_request(struct intel_engine_cs *engine, struct i915_request *rq) { - struct list_head *pl; - LIST_HEAD(list); + struct list_head *pos = &rq->sched.waiters_list; + struct i915_request *rn; + LIST_HEAD(dfs); + int prio; lockdep_assert_held(&engine->active.lock); GEM_BUG_ON(!test_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags)); + prio = rq_prio(rq); + /* * When we defer a request, we must maintain its order with respect * to those that are waiting upon it. So we traverse its chain of * waiters and move any that are earlier than the request to after it. */ - pl = lookup_priolist(engine, rq_prio(rq)); + rq->sched.dfs.next = NULL; do { - struct i915_dependency *p; - - GEM_BUG_ON(i915_request_is_active(rq)); - list_move_tail(&rq->sched.link, pl); - - for_each_waiter(p, rq) { + list_for_each_continue(pos, &rq->sched.waiters_list) { + struct i915_dependency *p = + list_entry(pos, typeof(*p), wait_link); struct i915_request *w = container_of(p->waiter, typeof(*w), sched); @@ -488,19 +489,44 @@ void __intel_engine_defer_request(struct intel_engine_cs *engine, __i915_request_has_started(w) && !__i915_request_is_complete(rq)); - if (!i915_request_is_ready(w)) + if (!i915_request_in_priority_queue(w)) continue; - if (rq_prio(w) < rq_prio(rq)) + /* + * We also need to reorder within the same priority. + * + * This is unlike priority-inheritance, where if the + * signaler already has a higher priority [earlier + * deadline] than us, we can ignore as it will be + * scheduled first. If a waiter already has the + * same priority, we still have to push it to the end + * of the list. This unfortunately means we cannot + * use the rq_deadline() itself as a 'visited' bit. + */ + if (rq_prio(w) < prio) continue; - GEM_BUG_ON(rq_prio(w) > rq_prio(rq)); - GEM_BUG_ON(i915_request_is_active(w)); - list_move_tail(&w->sched.link, &list); + GEM_BUG_ON(rq_prio(w) != prio); + + /* Remember our position along this branch */ + rq = stack_push(w, rq, pos); + pos = &rq->sched.waiters_list; } - rq = list_first_entry_or_null(&list, typeof(*rq), sched.link); - } while (rq); + /* Note list is reversed for waiters wrt signal hierarchy */ + GEM_BUG_ON(rq->engine != engine); + GEM_BUG_ON(!i915_request_in_priority_queue(rq)); + list_move(&rq->sched.link, &dfs); + + /* Track our visit, and prevent duplicate processing */ + clear_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); + } while ((rq = stack_pop(rq, &pos))); + + pos = lookup_priolist(engine, prio); + list_for_each_entry_safe(rq, rn, &dfs, sched.link) { + set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); + list_add_tail(&rq->sched.link, pos); + } } static void queue_request(struct intel_engine_cs *engine, -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx