From patchwork Wed Oct 16 12:20:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Tvrtko Ursulin X-Patchwork-Id: 13838264 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 72B77D1AD50 for ; Wed, 16 Oct 2024 12:20:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D171C10E065; Wed, 16 Oct 2024 12:20:21 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.b="d7k8kpoH"; dkim-atps=neutral Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) by gabe.freedesktop.org (Postfix) with ESMTPS id DC0D410E606 for ; Wed, 16 Oct 2024 12:20:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=lLhbPUENwr+vb4uA+4Ct/oqOIg2vO14J4FiDu7CYtfw=; b=d7k8kpoHo5PrkMzFNk4Arz8Afp rEA9LNQ03/meFPTKJFPL0L6KEbV3bKtdEKT57z6MisVLt1neCq82o+RRhz5AwA7OWrLueKo0hBw+l iwRH+1JC1OE8TSI5AMkRXlY1PBgFOIem32dWnuS3w0ynwEFTp/YS6ZeCCGzyRE3aIQil5XNuPjjYK bzLuTF+CGk5DQpzvM1WGekD2cwLyp6A6xb7zNPieDqOZiG2lCl53zpNZziComU1NrUmazRKeYY8RF +3BCD6sWSnB/hOauRe4wLNKXb0YWSdAJeHv6oZig8j/zQHaICACBp3hKbePki2uOawC0N6sXIyqOs yHhBJPfw==; Received: from [90.241.98.187] (helo=localhost) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1t130l-00Ajiu-3M; Wed, 16 Oct 2024 14:20:19 +0200 From: Tvrtko Ursulin To: dri-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, Tvrtko Ursulin , =?utf-8?q?Christian_K=C3=B6nig?= , Alex Deucher , Luben Tuikov , Matthew Brost , Philipp Stanner Subject: [PATCH 4/5] drm/sched: Re-group and rename the entity run-queue lock Date: Wed, 16 Oct 2024 13:20:12 +0100 Message-ID: <20241016122013.7857-5-tursulin@igalia.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20241016122013.7857-1-tursulin@igalia.com> References: <20241016122013.7857-1-tursulin@igalia.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Tvrtko Ursulin When writing to a drm_sched_entity's run-queue, writers are protected through the lock drm_sched_entity.rq_lock. This naming, however, frequently collides with the separate internal lock of struct drm_sched_rq, resulting in uses like this: spin_lock(&entity->rq_lock); spin_lock(&entity->rq->lock); Rename drm_sched_entity.rq_lock to improve readability. While at it, re-order that struct's members to make it more obvious what the lock protects. v2: * Rename some rq_lock straddlers in kerneldoc, improve commit text. (Philipp) Signed-off-by: Tvrtko Ursulin Suggested-by: Christian König Cc: Alex Deucher Cc: Luben Tuikov Cc: Matthew Brost Cc: Philipp Stanner Reviewed-by: Christian König --- drivers/gpu/drm/scheduler/sched_entity.c | 28 ++++++++++++------------ drivers/gpu/drm/scheduler/sched_main.c | 2 +- include/drm/gpu_scheduler.h | 21 +++++++++--------- 3 files changed, 26 insertions(+), 25 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index b72cba292839..c013c2b49aa5 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -105,7 +105,7 @@ int drm_sched_entity_init(struct drm_sched_entity *entity, /* We start in an idle state. */ complete_all(&entity->entity_idle); - spin_lock_init(&entity->rq_lock); + spin_lock_init(&entity->lock); spsc_queue_init(&entity->job_queue); atomic_set(&entity->fence_seq, 0); @@ -133,10 +133,10 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity, { WARN_ON(!num_sched_list || !sched_list); - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); entity->sched_list = sched_list; entity->num_sched_list = num_sched_list; - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); } EXPORT_SYMBOL(drm_sched_entity_modify_sched); @@ -244,10 +244,10 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity) if (!entity->rq) return; - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); entity->stopped = true; drm_sched_rq_remove_entity(entity->rq, entity); - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); /* Make sure this entity is not used by the scheduler at the moment */ wait_for_completion(&entity->entity_idle); @@ -396,9 +396,9 @@ static void drm_sched_entity_wakeup(struct dma_fence *f, void drm_sched_entity_set_priority(struct drm_sched_entity *entity, enum drm_sched_priority priority) { - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); entity->priority = priority; - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); } EXPORT_SYMBOL(drm_sched_entity_set_priority); @@ -515,10 +515,10 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity) next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue)); if (next) { - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); drm_sched_rq_update_fifo_locked(entity, next->submit_ts); - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); } } @@ -559,14 +559,14 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity) if (fence && !dma_fence_is_signaled(fence)) return; - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); sched = drm_sched_pick_best(entity->sched_list, entity->num_sched_list); rq = sched ? sched->sched_rq[entity->priority] : NULL; if (rq != entity->rq) { drm_sched_rq_remove_entity(entity->rq, entity); entity->rq = rq; } - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); if (entity->num_sched_list == 1) entity->sched_list = NULL; @@ -605,9 +605,9 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job) struct drm_sched_rq *rq; /* Add the entity to the run queue */ - spin_lock(&entity->rq_lock); + spin_lock(&entity->lock); if (entity->stopped) { - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); DRM_ERROR("Trying to push to a killed entity\n"); return; @@ -621,7 +621,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job) if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) drm_sched_rq_update_fifo_locked(entity, submit_ts); - spin_unlock(&entity->rq_lock); + spin_unlock(&entity->lock); drm_sched_wakeup(sched); } diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 07ee386b8e4b..2670bf9f34b2 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -176,7 +176,7 @@ void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity, ktime_t ts * for entity from within concurrent drm_sched_entity_select_rq and the * other to update the rb tree structure. */ - lockdep_assert_held(&entity->rq_lock); + lockdep_assert_held(&entity->lock); spin_lock(&entity->rq->lock); diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h index b6d095074c19..8ef33765b3b8 100644 --- a/include/drm/gpu_scheduler.h +++ b/include/drm/gpu_scheduler.h @@ -96,14 +96,22 @@ struct drm_sched_entity { */ struct list_head list; + /** + * @lock: + * + * Lock protecting the run-queue (@rq) to which this entity belongs, + * @priority and the list of schedulers (@sched_list, @num_sched_list). + */ + spinlock_t lock; + /** * @rq: * * Runqueue on which this entity is currently scheduled. * * FIXME: Locking is very unclear for this. Writers are protected by - * @rq_lock, but readers are generally lockless and seem to just race - * with not even a READ_ONCE. + * @lock, but readers are generally lockless and seem to just race with + * not even a READ_ONCE. */ struct drm_sched_rq *rq; @@ -136,17 +144,10 @@ struct drm_sched_entity { * @priority: * * Priority of the entity. This can be modified by calling - * drm_sched_entity_set_priority(). Protected by &rq_lock. + * drm_sched_entity_set_priority(). Protected by &lock. */ enum drm_sched_priority priority; - /** - * @rq_lock: - * - * Lock to modify the runqueue to which this entity belongs. - */ - spinlock_t rq_lock; - /** * @job_queue: the list of jobs of this entity. */