From patchwork Mon Jan 6 10:22:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11319011 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 13CD1930 for ; Mon, 6 Jan 2020 10:22:59 +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 EFBFC20731 for ; Mon, 6 Jan 2020 10:22:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EFBFC20731 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 093AC6E239; Mon, 6 Jan 2020 10:22:54 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id C74996E231 for ; Mon, 6 Jan 2020 10:22:50 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 19782269-1500050 for multiple; Mon, 06 Jan 2020 10:22:30 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Mon, 6 Jan 2020 10:22:26 +0000 Message-Id: <20200106102227.2438478-7-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.25.0.rc1 In-Reply-To: <20200106102227.2438478-1-chris@chris-wilson.co.uk> References: <20200106102227.2438478-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 7/8] drm/i915/gt: Drop mutex serialisation between context pin/unpin 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" The last remaining reason for serialising the pin/unpin of the intel_context is to ensure that our preallocated wakerefs are not consumed too early (i.e. the unpin of the previous phase does not emit the idle barriers for this phase before we even submit). All of the other operations within the context pin/unpin are supposed to be atomic... Therefore, we can reduce the serialisation to being just on the i915_active.preallocated_barriers itself and drop the nested pin_mutex from intel_context_unpin(). Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Maarten Lankhorst Reviewed-by: Maarten Lankhorst --- drivers/gpu/drm/i915/gt/intel_context.c | 18 +++++------------- drivers/gpu/drm/i915/i915_active.c | 19 +++++++++++++++---- 2 files changed, 20 insertions(+), 17 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index 4d0bc1478ccd..34ec958d400e 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -86,22 +86,14 @@ int __intel_context_do_pin(struct intel_context *ce) void intel_context_unpin(struct intel_context *ce) { - if (likely(atomic_add_unless(&ce->pin_count, -1, 1))) + if (!atomic_dec_and_test(&ce->pin_count)) return; - /* We may be called from inside intel_context_pin() to evict another */ - intel_context_get(ce); - mutex_lock_nested(&ce->pin_mutex, SINGLE_DEPTH_NESTING); - - if (likely(atomic_dec_and_test(&ce->pin_count))) { - CE_TRACE(ce, "retire\n"); + CE_TRACE(ce, "unpin\n"); + ce->ops->unpin(ce); - ce->ops->unpin(ce); - - intel_context_active_release(ce); - } - - mutex_unlock(&ce->pin_mutex); + intel_context_get(ce); + intel_context_active_release(ce); intel_context_put(ce); } diff --git a/drivers/gpu/drm/i915/i915_active.c b/drivers/gpu/drm/i915/i915_active.c index cfe09964622b..f3da5c06f331 100644 --- a/drivers/gpu/drm/i915/i915_active.c +++ b/drivers/gpu/drm/i915/i915_active.c @@ -605,12 +605,15 @@ int i915_active_acquire_preallocate_barrier(struct i915_active *ref, struct intel_engine_cs *engine) { intel_engine_mask_t tmp, mask = engine->mask; + struct llist_node *pos = NULL, *next; struct intel_gt *gt = engine->gt; - struct llist_node *pos, *next; int err; GEM_BUG_ON(i915_active_is_idle(ref)); - GEM_BUG_ON(!llist_empty(&ref->preallocated_barriers)); + + /* Wait until the previous preallocation is completed */ + while (!llist_empty(&ref->preallocated_barriers)) + cond_resched(); /* * Preallocate a node for each physical engine supporting the target @@ -653,16 +656,24 @@ int i915_active_acquire_preallocate_barrier(struct i915_active *ref, GEM_BUG_ON(rcu_access_pointer(node->base.fence) != ERR_PTR(-EAGAIN)); GEM_BUG_ON(barrier_to_engine(node) != engine); - llist_add(barrier_to_ll(node), &ref->preallocated_barriers); + next = barrier_to_ll(node); + next->next = pos; + if (!pos) + pos = next; intel_engine_pm_get(engine); } + GEM_BUG_ON(!llist_empty(&ref->preallocated_barriers)); + llist_add_batch(next, pos, &ref->preallocated_barriers); + return 0; unwind: - llist_for_each_safe(pos, next, take_preallocated_barriers(ref)) { + while (pos) { struct active_node *node = barrier_from_ll(pos); + pos = pos->next; + atomic_dec(&ref->count); intel_engine_pm_put(barrier_to_engine(node));