From patchwork Fri Dec 1 10:36:03 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Stach X-Patchwork-Id: 10086797 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7BD016035E for ; Fri, 1 Dec 2017 10:37:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8424A29FE8 for ; Fri, 1 Dec 2017 10:37:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 77DF02A0D6; Fri, 1 Dec 2017 10:37:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CD90429FE8 for ; Fri, 1 Dec 2017 10:37:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6CED06ECE1; Fri, 1 Dec 2017 10:36:31 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.ORG Delivered-To: dri-devel@lists.freedesktop.ORG Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1446B6ECBE for ; Fri, 1 Dec 2017 10:36:26 +0000 (UTC) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7] helo=dude.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.84_2) (envelope-from ) id 1eKigD-0004JB-8k; Fri, 01 Dec 2017 11:36:25 +0100 From: Lucas Stach To: etnaviv@lists.freedesktop.org Subject: [PATCH 06/27] drm/etnaviv: get rid of userptr worker Date: Fri, 1 Dec 2017 11:36:03 +0100 Message-Id: <20171201103624.6565-7-l.stach@pengutronix.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171201103624.6565-1-l.stach@pengutronix.de> References: <20171201103624.6565-1-l.stach@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: dri-devel@lists.freedesktop.org Cc: patchwork-lst@pengutronix.de, kernel@pengutronix.de, dri-devel@lists.freedesktop.org, Russell King X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP All code paths which populate userptr BOs are fine with the get_pages function taking the mmap_sem lock. This allows to get rid of the pretty involved architecture with a worker being scheduled if the mmap_sem needs to be taken, but instead call GUP directly and allow it to take the lock if necessary. This simplifies the code a lot and removes the possibility of this function returning -EAGAIN, which complicates object population handling at the callers. Signed-off-by: Lucas Stach --- drivers/gpu/drm/etnaviv/etnaviv_gem.c | 146 +++++----------------------------- drivers/gpu/drm/etnaviv/etnaviv_gem.h | 3 +- 2 files changed, 23 insertions(+), 126 deletions(-) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c index a52220eeee45..fcc969fa0e69 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c @@ -705,141 +705,41 @@ int etnaviv_gem_new_private(struct drm_device *dev, size_t size, u32 flags, return 0; } -struct get_pages_work { - struct work_struct work; - struct mm_struct *mm; - struct task_struct *task; - struct etnaviv_gem_object *etnaviv_obj; -}; - -static struct page **etnaviv_gem_userptr_do_get_pages( - struct etnaviv_gem_object *etnaviv_obj, struct mm_struct *mm, struct task_struct *task) -{ - int ret = 0, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT; - struct page **pvec; - uintptr_t ptr; - unsigned int flags = 0; - - pvec = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); - if (!pvec) - return ERR_PTR(-ENOMEM); - - if (!etnaviv_obj->userptr.ro) - flags |= FOLL_WRITE; - - pinned = 0; - ptr = etnaviv_obj->userptr.ptr; - - down_read(&mm->mmap_sem); - while (pinned < npages) { - ret = get_user_pages_remote(task, mm, ptr, npages - pinned, - flags, pvec + pinned, NULL, NULL); - if (ret < 0) - break; - - ptr += ret * PAGE_SIZE; - pinned += ret; - } - up_read(&mm->mmap_sem); - - if (ret < 0) { - release_pages(pvec, pinned); - kvfree(pvec); - return ERR_PTR(ret); - } - - return pvec; -} - -static void __etnaviv_gem_userptr_get_pages(struct work_struct *_work) -{ - struct get_pages_work *work = container_of(_work, typeof(*work), work); - struct etnaviv_gem_object *etnaviv_obj = work->etnaviv_obj; - struct page **pvec; - - pvec = etnaviv_gem_userptr_do_get_pages(etnaviv_obj, work->mm, work->task); - - mutex_lock(&etnaviv_obj->lock); - if (IS_ERR(pvec)) { - etnaviv_obj->userptr.work = ERR_CAST(pvec); - } else { - etnaviv_obj->userptr.work = NULL; - etnaviv_obj->pages = pvec; - } - - mutex_unlock(&etnaviv_obj->lock); - drm_gem_object_put_unlocked(&etnaviv_obj->base); - - mmput(work->mm); - put_task_struct(work->task); - kfree(work); -} - static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj) { struct page **pvec = NULL; - struct get_pages_work *work; - struct mm_struct *mm; - int ret, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT; + struct etnaviv_gem_userptr *userptr = &etnaviv_obj->userptr; + int ret, pinned = 0, npages = etnaviv_obj->base.size >> PAGE_SHIFT; might_lock_read(¤t->mm->mmap_sem); - if (etnaviv_obj->userptr.work) { - if (IS_ERR(etnaviv_obj->userptr.work)) { - ret = PTR_ERR(etnaviv_obj->userptr.work); - etnaviv_obj->userptr.work = NULL; - } else { - ret = -EAGAIN; - } - return ret; - } + if (userptr->mm != current->mm) + return -EPERM; - mm = get_task_mm(etnaviv_obj->userptr.task); - pinned = 0; - if (mm == current->mm) { - pvec = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); - if (!pvec) { - mmput(mm); - return -ENOMEM; - } + pvec = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); + if (!pvec) + return -ENOMEM; + + do { + unsigned num_pages = npages - pinned; + uint64_t ptr = userptr->ptr + pinned * PAGE_SIZE; + struct page **pages = pvec + pinned; - pinned = __get_user_pages_fast(etnaviv_obj->userptr.ptr, npages, - !etnaviv_obj->userptr.ro, pvec); - if (pinned < 0) { + ret = get_user_pages_fast(ptr, num_pages, + !userptr->ro ? FOLL_WRITE : 0, pages); + if (ret < 0) { + release_pages(pvec, pinned); kvfree(pvec); - mmput(mm); - return pinned; + return ret; } - if (pinned == npages) { - etnaviv_obj->pages = pvec; - mmput(mm); - return 0; - } - } - - release_pages(pvec, pinned); - kvfree(pvec); - - work = kmalloc(sizeof(*work), GFP_KERNEL); - if (!work) { - mmput(mm); - return -ENOMEM; - } - - get_task_struct(current); - drm_gem_object_get(&etnaviv_obj->base); - - work->mm = mm; - work->task = current; - work->etnaviv_obj = etnaviv_obj; + pinned += ret; - etnaviv_obj->userptr.work = &work->work; - INIT_WORK(&work->work, __etnaviv_gem_userptr_get_pages); + } while (pinned < npages); - etnaviv_queue_work(etnaviv_obj->base.dev, &work->work); + etnaviv_obj->pages = pvec; - return -EAGAIN; + return 0; } static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj) @@ -855,7 +755,6 @@ static void etnaviv_gem_userptr_release(struct etnaviv_gem_object *etnaviv_obj) release_pages(etnaviv_obj->pages, npages); kvfree(etnaviv_obj->pages); } - put_task_struct(etnaviv_obj->userptr.task); } static int etnaviv_gem_userptr_mmap_obj(struct etnaviv_gem_object *etnaviv_obj, @@ -885,9 +784,8 @@ int etnaviv_gem_new_userptr(struct drm_device *dev, struct drm_file *file, lockdep_set_class(&etnaviv_obj->lock, &etnaviv_userptr_lock_class); etnaviv_obj->userptr.ptr = ptr; - etnaviv_obj->userptr.task = current; + etnaviv_obj->userptr.mm = current->mm; etnaviv_obj->userptr.ro = !(flags & ETNA_USERPTR_WRITE); - get_task_struct(current); etnaviv_gem_obj_add(dev, &etnaviv_obj->base); diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.h b/drivers/gpu/drm/etnaviv/etnaviv_gem.h index 00bd9c851a02..d1a7d040ac97 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.h +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.h @@ -26,8 +26,7 @@ struct etnaviv_gem_object; struct etnaviv_gem_userptr { uintptr_t ptr; - struct task_struct *task; - struct work_struct *work; + struct mm_struct *mm; bool ro; };