From patchwork Mon Mar 20 14:43:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rob Clark X-Patchwork-Id: 13181344 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77583C7618A for ; Mon, 20 Mar 2023 14:44:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231851AbjCTOon (ORCPT ); Mon, 20 Mar 2023 10:44:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231857AbjCTOok (ORCPT ); Mon, 20 Mar 2023 10:44:40 -0400 Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0B2DCA1A; Mon, 20 Mar 2023 07:44:38 -0700 (PDT) Received: by mail-pl1-x62b.google.com with SMTP id u5so12652623plq.7; Mon, 20 Mar 2023 07:44:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679323478; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=xALpMXlLTSMvOfS7mQNvHfzG9+8QM3cmx9b7Fz6Q2XU=; b=cxu8fcc47sheJUocs3NFK/ej2kra9Ypkl7pCx1H1P5vOekErq1/GNU3/ZBsh7fug/U LK5SzMY1CdLJhSlItGMRB+oN2kKcpG9ZezdZTN4n8Us/IaCGxAzVEcp9zoIzcbsHXM8l Qze0Vuq2K4bx7XB8PZONqv84P/6H9hG3kl7ovKb5I6Z0JnHdaUA2grKNAlEuYnpDmN+B Y9CLZCVJ6ye3i6QM7sDrald94pji9aWZ+2cy0EOHNDHwDIaL6b6wQ2WpqdFMnc1TBHeR qnuRIQoDVOVCXCBRpQ2sohXgh4ltYqi2IkT24bat3p9pR9f1dZscLLR8ov0SK99wX8qm HqPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679323478; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=xALpMXlLTSMvOfS7mQNvHfzG9+8QM3cmx9b7Fz6Q2XU=; b=sNva6z4hfKo7CcVhs4Ogj8oEn1utR9+RmVVISSiwsyw6v8wHdyiFLjzmje9aCvHVR9 uEV3FvdYvpKRZuRr/mp/1Z5cNl8HjsFq2HGIePxF7F9uzPQ3e9G/ZYw4dEuWl3dEMQOD 5MpUHWolH/sXuD93CU3A9OpC7CnIP7DEIV2JCKuc1+9QMcjNY0qDECxDgB0pPyLr91/K ij1+jFWMKoBLpxxcdNOars3/oEq7C3X/PItbVNpo5LC8eVcaudvtDXn7irWgNoJZEnSz U955qNJb/CoLE+zh9GpeIhx/FTcY7MqmK0z4vm6/GNlUwn3Ddoca0ksgRpFCkxDtX4N4 Lq3Q== X-Gm-Message-State: AO0yUKVVxLXhK86X99fHkVGr1nayN+mhDOhSUbIfKmEAmvpW+4cDfrQ7 EEJrWS0jgyqLESi+D+1VEa0= X-Google-Smtp-Source: AK7set/Og7pcuw4IzsENyS7Re6THWUo/30QuP9+MbL2JloNr5T9/L0e5eyWIxk080vd7BjvX4FSQ2A== X-Received: by 2002:a05:6a20:7b05:b0:da:39a5:6e66 with SMTP id s5-20020a056a207b0500b000da39a56e66mr920491pzh.18.1679323478303; Mon, 20 Mar 2023 07:44:38 -0700 (PDT) Received: from localhost ([2a00:79e1:abd:4a00:61b:48ed:72ab:435b]) by smtp.gmail.com with ESMTPSA id r13-20020a63e50d000000b004fb26a80875sm6389111pgh.22.2023.03.20.07.44.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Mar 2023 07:44:37 -0700 (PDT) From: Rob Clark To: dri-devel@lists.freedesktop.org Cc: Daniel Vetter , freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, Rob Clark , Rob Clark , Abhinav Kumar , Dmitry Baryshkov , Sean Paul , David Airlie , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 04/23] drm/msm: Decouple vma tracking from obj lock Date: Mon, 20 Mar 2023 07:43:26 -0700 Message-Id: <20230320144356.803762-5-robdclark@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230320144356.803762-1-robdclark@gmail.com> References: <20230320144356.803762-1-robdclark@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org From: Rob Clark We need to use the inuse count to track that a BO is pinned until we have the hw_fence. But we want to remove the obj lock from the job_run() path as this could deadlock against reclaim/shrinker (because it is blocking the hw_fence from eventually being signaled). So split that tracking out into a per-vma lock with narrower scope. Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/msm_gem.h | 1 + drivers/gpu/drm/msm/msm_gem_vma.c | 44 ++++++++++++++++++++++++---- drivers/gpu/drm/msm/msm_ringbuffer.c | 2 +- 3 files changed, 40 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h index d3219c523034..1929f09c5b0d 100644 --- a/drivers/gpu/drm/msm/msm_gem.h +++ b/drivers/gpu/drm/msm/msm_gem.h @@ -59,6 +59,7 @@ struct msm_fence_context; struct msm_gem_vma { struct drm_mm_node node; + spinlock_t lock; uint64_t iova; struct msm_gem_address_space *aspace; struct list_head list; /* node in msm_gem_object::vmas */ diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index 2827679dc39a..98287ed99960 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -40,19 +40,28 @@ msm_gem_address_space_get(struct msm_gem_address_space *aspace) bool msm_gem_vma_inuse(struct msm_gem_vma *vma) { + bool ret = true; + + spin_lock(&vma->lock); + if (vma->inuse > 0) - return true; + goto out; while (vma->fence_mask) { unsigned idx = ffs(vma->fence_mask) - 1; if (!msm_fence_completed(vma->fctx[idx], vma->fence[idx])) - return true; + goto out; vma->fence_mask &= ~BIT(idx); } - return false; + ret = false; + +out: + spin_unlock(&vma->lock); + + return ret; } /* Actually unmap memory for the vma */ @@ -73,8 +82,7 @@ void msm_gem_vma_purge(struct msm_gem_vma *vma) vma->mapped = false; } -/* Remove reference counts for the mapping */ -void msm_gem_vma_unpin(struct msm_gem_vma *vma) +static void vma_unpin_locked(struct msm_gem_vma *vma) { if (GEM_WARN_ON(!vma->inuse)) return; @@ -82,13 +90,23 @@ void msm_gem_vma_unpin(struct msm_gem_vma *vma) vma->inuse--; } +/* Remove reference counts for the mapping */ +void msm_gem_vma_unpin(struct msm_gem_vma *vma) +{ + spin_lock(&vma->lock); + vma_unpin_locked(vma); + spin_unlock(&vma->lock); +} + /* Replace pin reference with fence: */ void msm_gem_vma_unpin_fenced(struct msm_gem_vma *vma, struct msm_fence_context *fctx) { + spin_lock(&vma->lock); vma->fctx[fctx->index] = fctx; vma->fence[fctx->index] = fctx->last_fence; vma->fence_mask |= BIT(fctx->index); - msm_gem_vma_unpin(vma); + vma_unpin_locked(vma); + spin_unlock(&vma->lock); } /* Map and pin vma: */ @@ -103,7 +121,9 @@ msm_gem_vma_map(struct msm_gem_vma *vma, int prot, return -EINVAL; /* Increase the usage counter */ + spin_lock(&vma->lock); vma->inuse++; + spin_unlock(&vma->lock); if (vma->mapped) return 0; @@ -113,11 +133,22 @@ msm_gem_vma_map(struct msm_gem_vma *vma, int prot, if (!aspace) return 0; + /* + * NOTE: iommu/io-pgtable can allocate pages, so we cannot hold + * a lock across map/unmap which is also used in the job_run() + * path, as this can cause deadlock in job_run() vs shrinker/ + * reclaim. + * + * Revisit this if we can come up with a scheme to pre-alloc pages + * for the pgtable in map/unmap ops. + */ ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt, size, prot); if (ret) { vma->mapped = false; + spin_lock(&vma->lock); vma->inuse--; + spin_unlock(&vma->lock); } return ret; @@ -148,6 +179,7 @@ struct msm_gem_vma *msm_gem_vma_new(struct msm_gem_address_space *aspace) if (!vma) return NULL; + spin_lock_init(&vma->lock); vma->aspace = aspace; return vma; diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c index 44a22b283730..31b4fbf96c36 100644 --- a/drivers/gpu/drm/msm/msm_ringbuffer.c +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c @@ -23,8 +23,8 @@ static struct dma_fence *msm_job_run(struct drm_sched_job *job) for (i = 0; i < submit->nr_bos; i++) { struct drm_gem_object *obj = &submit->bos[i].obj->base; - msm_gem_lock(obj); msm_gem_vma_unpin_fenced(submit->bos[i].vma, fctx); + msm_gem_lock(obj); msm_gem_unpin_locked(obj); msm_gem_unlock(obj); submit->bos[i].flags &= ~(BO_VMA_PINNED | BO_OBJ_PINNED);