From patchwork Thu Apr 8 09:54:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Stevens X-Patchwork-Id: 417788 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 44C5AC433ED for ; Thu, 8 Apr 2021 09:54:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0FE26611EF for ; Thu, 8 Apr 2021 09:54:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231305AbhDHJyx (ORCPT ); Thu, 8 Apr 2021 05:54:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231301AbhDHJyw (ORCPT ); Thu, 8 Apr 2021 05:54:52 -0400 Received: from mail-pf1-x429.google.com (mail-pf1-x429.google.com [IPv6:2607:f8b0:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 310B4C061761 for ; Thu, 8 Apr 2021 02:54:40 -0700 (PDT) Received: by mail-pf1-x429.google.com with SMTP id c17so1421450pfn.6 for ; Thu, 08 Apr 2021 02:54:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=F06Z1RXUI5OZQHllx6yIelYubQ59fvVFVd2c1q8aYFo=; b=lFey3WOVaEoUGK+gffnBEpyZ85Q8vR72KNL7iQWslR0Dsuw+Qfd9pWdCFEMJN0S2Lf lDfiSrMZ0bvyr9HpQ1mdr0wOzq6x7HAf4Ltx7i6kZuMn22oHwfvSly1Sw5P23rSLVzCc Eiij/wKY6lESQsif5OiYrqsXIGqyONMMct5mk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=F06Z1RXUI5OZQHllx6yIelYubQ59fvVFVd2c1q8aYFo=; b=qH6FTw3O5/RLNbuJe9qwEJCp3Role2yaPGWlSsqazwYlH4M0kMs84pzDcAHYX1G4RT QLWyDZ/BSxbQBco89nAoZRuUa+Cg00pK0r8WKSvDI1RfyGIAA3q6EcAMAhZxzR2J3WSS cM6IPF3f7lxsE33YIRXMe34fZuciEX4lITa3GPs2Hv0Q6AsmiKuHhmM6Lg0lYmQrgyQG QtfVcCtNavOm1YsQerAoE72/KFVG8SoMlvXnBLzb4Uv4EKBXhY3mnhA0RsybTNdD2H3d UDSgkFeKa9fvhX4CN9LvegpiSutm5Gj/YtEC6rZPlGkukCvQQz3hTzTy8nte4h5A7to7 8+Jg== X-Gm-Message-State: AOAM5303DqtpvXKTkwj7ahyw4JyrBcoiOb5AikakRs2VlvZ2rkt3tKyq oJ2BwzWZEeP/lP0jbQyvUqfBzg== X-Google-Smtp-Source: ABdhPJxqkTB+8ooQy09dyBF9z9TbQVzPFo13ucXTs4ZmBx6F2XZyy5mEcW4yJMjsd5Y9vdSh3MDdMA== X-Received: by 2002:a63:f056:: with SMTP id s22mr7279239pgj.369.1617875679652; Thu, 08 Apr 2021 02:54:39 -0700 (PDT) Received: from localhost ([2401:fa00:8f:203:25d8:8458:73e8:75ac]) by smtp.gmail.com with UTF8SMTPSA id js16sm7528068pjb.21.2021.04.08.02.54.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 08 Apr 2021 02:54:39 -0700 (PDT) From: David Stevens X-Google-Original-From: David Stevens To: =?utf-8?q?Christian_K=C3=B6nig?= Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Sumit Semwal , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, David Stevens Subject: [PATCH v3] drm/syncobj: use newly allocated stub fences Date: Thu, 8 Apr 2021 18:54:28 +0900 Message-Id: <20210408095428.3983055-1-stevensd@google.com> X-Mailer: git-send-email 2.31.0.208.g409f899ff0-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: David Stevens Allocate a new private stub fence in drm_syncobj_assign_null_handle, instead of using a static stub fence. When userspace creates a fence with DRM_SYNCOBJ_CREATE_SIGNALED or when userspace signals a fence via DRM_IOCTL_SYNCOBJ_SIGNAL, the timestamp obtained when the fence is exported and queried with SYNC_IOC_FILE_INFO should match when the fence's status was changed from the perspective of userspace, which is during the respective ioctl. When a static stub fence started being used in by these ioctls, this behavior changed. Instead, the timestamp returned by SYNC_IOC_FILE_INFO became the first time anything used the static stub fence, which has no meaning to userspace. Signed-off-by: David Stevens --- v2 -> v3: - reuse the static stub spinlock v1 -> v2: - checkpatch style fixes drivers/dma-buf/dma-fence.c | 27 ++++++++++++++++++++++++++- drivers/gpu/drm/drm_syncobj.c | 25 +++++++++++++++++++------ include/linux/dma-fence.h | 1 + 3 files changed, 46 insertions(+), 7 deletions(-) diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c index d64fc03929be..ce0f5eff575d 100644 --- a/drivers/dma-buf/dma-fence.c +++ b/drivers/dma-buf/dma-fence.c @@ -123,7 +123,9 @@ static const struct dma_fence_ops dma_fence_stub_ops = { /** * dma_fence_get_stub - return a signaled fence * - * Return a stub fence which is already signaled. + * Return a stub fence which is already signaled. The fence's + * timestamp corresponds to the first time after boot this + * function is called. */ struct dma_fence *dma_fence_get_stub(void) { @@ -141,6 +143,29 @@ struct dma_fence *dma_fence_get_stub(void) } EXPORT_SYMBOL(dma_fence_get_stub); +/** + * dma_fence_allocate_private_stub - return a private, signaled fence + * + * Return a newly allocated and signaled stub fence. + */ +struct dma_fence *dma_fence_allocate_private_stub(void) +{ + struct dma_fence *fence; + + fence = kzalloc(sizeof(*fence), GFP_KERNEL); + if (fence == NULL) + return ERR_PTR(-ENOMEM); + + dma_fence_init(fence, + &dma_fence_stub_ops, + &dma_fence_stub_lock, + 0, 0); + dma_fence_signal(fence); + + return fence; +} +EXPORT_SYMBOL(dma_fence_allocate_private_stub); + /** * dma_fence_context_alloc - allocate an array of fence contexts * @num: amount of contexts to allocate diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 349146049849..a54aa850d143 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -350,12 +350,16 @@ EXPORT_SYMBOL(drm_syncobj_replace_fence); * * Assign a already signaled stub fence to the sync object. */ -static void drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj) +static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj) { - struct dma_fence *fence = dma_fence_get_stub(); + struct dma_fence *fence = dma_fence_allocate_private_stub(); + + if (IS_ERR(fence)) + return PTR_ERR(fence); drm_syncobj_replace_fence(syncobj, fence); dma_fence_put(fence); + return 0; } /* 5s default for wait submission */ @@ -469,6 +473,7 @@ EXPORT_SYMBOL(drm_syncobj_free); int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, struct dma_fence *fence) { + int ret; struct drm_syncobj *syncobj; syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL); @@ -479,8 +484,13 @@ int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, INIT_LIST_HEAD(&syncobj->cb_list); spin_lock_init(&syncobj->lock); - if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) - drm_syncobj_assign_null_handle(syncobj); + if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) { + ret = drm_syncobj_assign_null_handle(syncobj); + if (ret < 0) { + drm_syncobj_put(syncobj); + return ret; + } + } if (fence) drm_syncobj_replace_fence(syncobj, fence); @@ -1322,8 +1332,11 @@ drm_syncobj_signal_ioctl(struct drm_device *dev, void *data, if (ret < 0) return ret; - for (i = 0; i < args->count_handles; i++) - drm_syncobj_assign_null_handle(syncobjs[i]); + for (i = 0; i < args->count_handles; i++) { + ret = drm_syncobj_assign_null_handle(syncobjs[i]); + if (ret < 0) + break; + } drm_syncobj_array_free(syncobjs, args->count_handles); diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index 9f12efaaa93a..6ffb4b2c6371 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -587,6 +587,7 @@ static inline signed long dma_fence_wait(struct dma_fence *fence, bool intr) } struct dma_fence *dma_fence_get_stub(void); +struct dma_fence *dma_fence_allocate_private_stub(void); u64 dma_fence_context_alloc(unsigned num); #define DMA_FENCE_TRACE(f, fmt, args...) \