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=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 E059FC433DF for ; Thu, 14 May 2020 12:40:55 +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 A28272065D for ; Thu, 14 May 2020 12:40:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="h+sQhZtv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A28272065D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch 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 0DF936EB37; Thu, 14 May 2020 12:40:55 +0000 (UTC) Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9B8AB6EB37 for ; Thu, 14 May 2020 12:40:54 +0000 (UTC) Received: by mail-wr1-x442.google.com with SMTP id j5so3899721wrq.2 for ; Thu, 14 May 2020 05:40:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=iRdEt0uWUWULnXap7eY+x8y55VAAx80JcgqWrmj1UZo=; b=h+sQhZtvUpzsE7u0G6pm/zL5JXYKaL1yLhWS6Pq72+Ua8pLyNowr9LdrLOVWecJILH az9dBoeVswk5R1w1n+RXe04kCd1yS7MtWRi54Y8YuTrnLCIcq8VF0q+hNIOKjkn5AhRo pNIaQJ9piDTghC5YahXX0+bgSk5XY4Nh/I060= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=iRdEt0uWUWULnXap7eY+x8y55VAAx80JcgqWrmj1UZo=; b=s1CYRz6xM6bdKcO0VizgHS6gSH/eD0MiV4vRj8zV0tD/cO0hApnIYmkIGdHeS2e1eN dPwkqQNsvRn9je2qwIQ/jziebEkHCo4H/esLnlnfFEBtIm2nVZvuIdJTT4hYJm6qYBJ/ 7nIosjQXj4MvD+haiUzSvJrw5nqeCHct/UlSo/dAt/lv+bF9OOrQkqyZ8qNwkQvyvrRL CzigY4dvcTzdSI2mCJuxLYEkfFjlwYJtNjVfZUse/CRCRD0wU8F/LGaosh7QaXImNxjx Mv8djcFw+WwIZCSm3YW/HTsBQDMSVkjvDEtxRip6ahU5as+utib15xiyIFjmjGpYWz0R a33w== X-Gm-Message-State: AOAM533k4L7UsvTfQ2MMNIUzio/B13bEa9ha0pOmIBF6OYwvkfhED83C MG6cikTCjHgcd6eM4LOkulUu0A== X-Google-Smtp-Source: ABdhPJz0oASI+8WqTKBSjYyZe8amgwA2EPSCm0fY1U9lSM97EKc59F1D2ZH6EyRWBos0nFeJNp57PQ== X-Received: by 2002:adf:db46:: with SMTP id f6mr5362260wrj.80.1589460053340; Thu, 14 May 2020 05:40:53 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id 77sm3981346wrc.6.2020.05.14.05.40.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 14 May 2020 05:40:52 -0700 (PDT) Date: Thu, 14 May 2020 14:40:50 +0200 From: Daniel Vetter To: Thomas Zimmermann Subject: Re: [PATCH 1/2] drm/shmem: Use cached mappings by default Message-ID: <20200514124050.GV206103@phenom.ffwll.local> References: <20200513150312.21421-1-tzimmermann@suse.de> <20200513150312.21421-2-tzimmermann@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200513150312.21421-2-tzimmermann@suse.de> X-Operating-System: Linux phenom 5.6.0-1-amd64 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: sam@ravnborg.org, airlied@linux.ie, emil.l.velikov@gmail.com, dri-devel@lists.freedesktop.org, kraxel@redhat.com, sean@poorly.run Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Wed, May 13, 2020 at 05:03:11PM +0200, Thomas Zimmermann wrote: > SHMEM-buffer backing storage is allocated from system memory; which is > typically cachable. Currently, only virtio uses cachable mappings; udl > uses its own vmap/mmap implementation for cachable mappings. Other > drivers default to writecombine mappings. I'm pretty sure this breaks all these drivers. quick grep on a few functions says this is used by lima, panfrost, v3d. And they definitely need uncached/wc stuff afaiui. Or I'm completely missing something? -Daniel > > Use cached mappings by default. The exception is pages imported via > dma-buf. DMA memory is usually not cached. > > Signed-off-by: Thomas Zimmermann > --- > drivers/gpu/drm/drm_gem_shmem_helper.c | 6 ++++-- > drivers/gpu/drm/virtio/virtgpu_object.c | 1 - > include/drm/drm_gem_shmem_helper.h | 4 ++-- > 3 files changed, 6 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c > index df31e5782eed1..1ce90325dfa31 100644 > --- a/drivers/gpu/drm/drm_gem_shmem_helper.c > +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c > @@ -259,7 +259,7 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem) > } else { > pgprot_t prot = PAGE_KERNEL; > > - if (!shmem->map_cached) > + if (shmem->map_wc) > prot = pgprot_writecombine(prot); > shmem->vaddr = vmap(shmem->pages, obj->size >> PAGE_SHIFT, > VM_MAP, prot); > @@ -546,7 +546,7 @@ int drm_gem_shmem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) > > vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND; > vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); > - if (!shmem->map_cached) > + if (shmem->map_wc) > vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot); > vma->vm_ops = &drm_gem_shmem_vm_ops; > > @@ -664,6 +664,8 @@ drm_gem_shmem_prime_import_sg_table(struct drm_device *dev, > if (IS_ERR(shmem)) > return ERR_CAST(shmem); > > + shmem->map_wc = false; /* dma-buf mappings use writecombine */ > + > shmem->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); > if (!shmem->pages) { > ret = -ENOMEM; > diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c > index 6ccbd01cd888c..80ba6b2b61668 100644 > --- a/drivers/gpu/drm/virtio/virtgpu_object.c > +++ b/drivers/gpu/drm/virtio/virtgpu_object.c > @@ -132,7 +132,6 @@ struct drm_gem_object *virtio_gpu_create_object(struct drm_device *dev, > > dshmem = &shmem->base.base; > dshmem->base.funcs = &virtio_gpu_shmem_funcs; > - dshmem->map_cached = true; > return &dshmem->base; > } > > diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h > index 294b2931c4cc0..a5bc082a77c48 100644 > --- a/include/drm/drm_gem_shmem_helper.h > +++ b/include/drm/drm_gem_shmem_helper.h > @@ -98,9 +98,9 @@ struct drm_gem_shmem_object { > unsigned int vmap_use_count; > > /** > - * @map_cached: map object cached (instead of using writecombine). > + * @map_wc: map object using writecombine (instead of cached). > */ > - bool map_cached; > + bool map_wc; > }; > > #define to_drm_gem_shmem_obj(obj) \ > -- > 2.26.2 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel