From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 265B8C433DB for ; Mon, 18 Jan 2021 21:48:22 +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 D40A422CB1 for ; Mon, 18 Jan 2021 21:48:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D40A422CB1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E9A216E598; Mon, 18 Jan 2021 21:48:18 +0000 (UTC) Received: from mail-oi1-x22d.google.com (mail-oi1-x22d.google.com [IPv6:2607:f8b0:4864:20::22d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 955126E593; Mon, 18 Jan 2021 21:48:17 +0000 (UTC) Received: by mail-oi1-x22d.google.com with SMTP id r189so9502355oih.4; Mon, 18 Jan 2021 13:48:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=q7A8rb8jN+pS3FHHOdO0I5mP7AmGsFHnFAO5rb9uabo=; b=Pz2CpHl1U4DOcaTKq6LijdF42rPeyA9Z+ZRbSsNA8Y9jCq4HC8dnWqTpCD1lhvd35n iAwrzfEevzI2amaRaxUwXFgbWxV8i2CjIEwndbmJ7Kbp0SM08xkLcJLJn/k2evA9ta+u KlzAVHp5KX3IVNsCGE0U7ME2ZeLeZJJ7mEsA/xA0kSY974NaLN+OVMN+XD4iPdpBfRdG Ya9CG4nBEuhb96hhdVIGWuYJvNvE4BrcasHQbxVDWq1vICdDuR5RxJLACvMWl8tjoYi3 5ec7Qx+/v6PRva8qe52bUq8O2mM/vk8eB4PA2TUgn5Uq8x0IlgSnpH6YSC45irY0AEJL kAhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=q7A8rb8jN+pS3FHHOdO0I5mP7AmGsFHnFAO5rb9uabo=; b=o+rNIjIC7CeR6wo0N4K94CcYrDkfwW5Cilv9BXdeeANEN+7QMI+A2s4VuY5ytm79zr vEYbXCuJbvLTO4tIPZBgqHKtYUNmGx6K+FFyK9C2haYCK657Ms9E2o7YKeY4NgRfw602 XcZmgyf/O7q5AWZsmmwsO5551njfdqFuRa5ivR09pcH5hK+YXov+mQlJIU3Ss5V/Jbjq 8z5f/mmzCjLe9Lf51TUjs938YLtEB0b6wIqc+GiKSMqjnjzAwOvl7QDyABPN65l1aVIk Z/OJ/KAy0/oZMMZNkdfR588KT2xST8BMn5nfG9NvfADpe4SD9m79mhB2wEtYz7RkLfOv lJDQ== X-Gm-Message-State: AOAM533eYRYlNOtgfXEtYvECUgQAGEPX7ngc08XgzJGpk3IUozWcJF2Q houPLObM/itIpIc01uFPS4ZpvzvJQn1et5Yoi8Y= X-Google-Smtp-Source: ABdhPJyoe8KDFlASSQgcRlftuFb9OxIFMGtNTf46zwBdYfESJxeSP/2RMF3bl8pbsgZV0E+oyWtf+QR4M/YNO3NFGdk= X-Received: by 2002:aca:6202:: with SMTP id w2mr775243oib.5.1611006496939; Mon, 18 Jan 2021 13:48:16 -0800 (PST) MIME-Version: 1.0 References: <1611003683-3534-1-git-send-email-andrey.grodzovsky@amd.com> <1611003683-3534-2-git-send-email-andrey.grodzovsky@amd.com> In-Reply-To: <1611003683-3534-2-git-send-email-andrey.grodzovsky@amd.com> From: Alex Deucher Date: Mon, 18 Jan 2021 16:48:05 -0500 Message-ID: Subject: Re: [PATCH v4 01/14] drm/ttm: Remap all page faults to per process dummy page. To: Andrey Grodzovsky 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: , Cc: Greg KH , =?UTF-8?Q?Christian_K=C3=B6nig?= , Maling list - DRI developers , amd-gfx list , Daniel Vetter , "Deucher, Alexander" , Qiang Yu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Jan 18, 2021 at 4:02 PM Andrey Grodzovsky wrote: > > On device removal reroute all CPU mappings to dummy page. > > v3: > Remove loop to find DRM file and instead access it > by vma->vm_file->private_data. Move dummy page installation > into a separate function. > > v4: > Map the entire BOs VA space into on demand allocated dummy page > on the first fault for that BO. > > Signed-off-by: Andrey Grodzovsky > --- > drivers/gpu/drm/ttm/ttm_bo_vm.c | 82 ++++++++++++++++++++++++++++++++++++++++- > include/drm/ttm/ttm_bo_api.h | 2 + > 2 files changed, 83 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > index 6dc96cf..ed89da3 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > @@ -34,6 +34,8 @@ > #include > #include > #include > +#include > +#include > #include > #include > #include > @@ -380,25 +382,103 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf, > } > EXPORT_SYMBOL(ttm_bo_vm_fault_reserved); > > +static void ttm_bo_release_dummy_page(struct drm_device *dev, void *res) > +{ > + struct page *dummy_page = (struct page *)res; > + > + __free_page(dummy_page); > +} > + > +vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot) > +{ > + struct vm_area_struct *vma = vmf->vma; > + struct ttm_buffer_object *bo = vma->vm_private_data; > + struct ttm_bo_device *bdev = bo->bdev; > + struct drm_device *ddev = bo->base.dev; > + vm_fault_t ret = VM_FAULT_NOPAGE; > + unsigned long address = vma->vm_start; > + unsigned long num_prefault = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; > + unsigned long pfn; > + struct page *page; > + int i; > + > + /* > + * Wait for buffer data in transit, due to a pipelined > + * move. > + */ > + ret = ttm_bo_vm_fault_idle(bo, vmf); > + if (unlikely(ret != 0)) > + return ret; > + > + /* Allocate new dummy page to map all the VA range in this VMA to it*/ > + page = alloc_page(GFP_KERNEL | __GFP_ZERO); > + if (!page) > + return VM_FAULT_OOM; > + > + pfn = page_to_pfn(page); > + > + /* > + * Prefault the entire VMA range right away to avoid further faults > + */ > + for (i = 0; i < num_prefault; ++i) { > + > + if (unlikely(address >= vma->vm_end)) > + break; > + > + if (vma->vm_flags & VM_MIXEDMAP) > + ret = vmf_insert_mixed_prot(vma, address, > + __pfn_to_pfn_t(pfn, PFN_DEV), > + prot); > + else > + ret = vmf_insert_pfn_prot(vma, address, pfn, prot); > + > + /* Never error on prefaulted PTEs */ > + if (unlikely((ret & VM_FAULT_ERROR))) { > + if (i == 0) > + return VM_FAULT_NOPAGE; > + else > + break; > + } > + > + address += PAGE_SIZE; > + } > + > + /* Set the page to be freed using drmm release action */ > + if (drmm_add_action_or_reset(ddev, ttm_bo_release_dummy_page, page)) > + return VM_FAULT_OOM; > + > + return ret; > +} > +EXPORT_SYMBOL(ttm_bo_vm_dummy_page); > + > vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf) > { > struct vm_area_struct *vma = vmf->vma; > pgprot_t prot; > struct ttm_buffer_object *bo = vma->vm_private_data; > + struct drm_device *ddev = bo->base.dev; > vm_fault_t ret; > + int idx; > > ret = ttm_bo_vm_reserve(bo, vmf); > if (ret) > return ret; > > prot = vma->vm_page_prot; > - ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT, 1); > + if (drm_dev_enter(ddev, &idx)) { > + ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT, 1); > + drm_dev_exit(idx); > + } else { > + ret = ttm_bo_vm_dummy_page(vmf, prot); > + } > if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) > return ret; > > dma_resv_unlock(bo->base.resv); > > return ret; > + > + return ret; Duplicate return here. Alex > } > EXPORT_SYMBOL(ttm_bo_vm_fault); > > diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h > index e17be32..12fb240 100644 > --- a/include/drm/ttm/ttm_bo_api.h > +++ b/include/drm/ttm/ttm_bo_api.h > @@ -643,4 +643,6 @@ void ttm_bo_vm_close(struct vm_area_struct *vma); > int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, > void *buf, int len, int write); > > +vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot); > + > #endif > -- > 2.7.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel