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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 6596CC2D0E2 for ; Tue, 22 Sep 2020 11:22:16 +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 E17392388B for ; Tue, 22 Sep 2020 11:22:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iLgsfzwx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E17392388B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BA5016E848; Tue, 22 Sep 2020 11:22:14 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id A59346E848; Tue, 22 Sep 2020 11:22:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=v+IUea/CGhLMdjL8zbCOPAxfGNu+qZhlo3dcebaU5kY=; b=iLgsfzwxwT611QKOl+WmOf2wbN /apXK6gTmDsVL/BXsA2nSeYw00AYm7of+qlZIT5seKhZdu6vVFYUh9VHKNyMaCNUtuxTWQsjq/fQb o+HH9FqL3yy9RUdN/gEnhHaw8zj6LjLVf/SMpazertMDW0M+AsMsYpsjEY6RqiGrpxc2TfV1v186b /dak9QRJGkXVmw5CYmBXsQSP0ryzf3Fj1FCPgdtdTrj8+Ud5C+5S63kHgzqMV4tMTbzbXE/7lodhh 8x3U5eQq2tiq0PS1EC76b9HHLbxCqMbJHon71YuO6JArA0Hf33RL3+JVtd3CmHZv47m4GshGX8kOv xhVaWjtQ==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKgMi-000579-Gi; Tue, 22 Sep 2020 11:21:44 +0000 Date: Tue, 22 Sep 2020 12:21:44 +0100 From: Matthew Wilcox To: Christoph Hellwig Message-ID: <20200922112144.GB32101@casper.infradead.org> References: <20200918163724.2511-1-hch@lst.de> <20200918163724.2511-4-hch@lst.de> <20200921191157.GX32101@casper.infradead.org> <20200922062249.GA30831@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200922062249.GA30831@lst.de> Subject: Re: [Intel-gfx] [PATCH 3/6] drm/i915: use vmap in shmem_pin_map X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Stefano Stabellini , linux-mm@kvack.org, Peter Zijlstra , intel-gfx@lists.freedesktop.org, x86@kernel.org, linux-kernel@vger.kernel.org, Minchan Kim , dri-devel@lists.freedesktop.org, xen-devel@lists.xenproject.org, Andrew Morton , Boris Ostrovsky , Nitin Gupta Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, Sep 22, 2020 at 08:22:49AM +0200, Christoph Hellwig wrote: > On Mon, Sep 21, 2020 at 08:11:57PM +0100, Matthew Wilcox wrote: > > This is awkward. I'd like it if we had a vfree() variant which called > > put_page() instead of __free_pages(). I'd like it even more if we > > used release_pages() instead of our own loop that called put_page(). > > Note that we don't need a new vfree variant, we can do this manually if > we want, take a look at kernel/dma/remap.c. But I thought this code > intentionally doesn't want to do that to avoid locking in the memory > for the pages array. Maybe the i915 maintainers can clarify. Actually, vfree() will work today; I cc'd you on a documentation update to make it clear that this is permitted. >From my current experience with the i915 shmem code, I think that the i915 maintainers are experts at graphics, and are unfamiliar with the MM. There are a number of places where they do things the hard way. _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx