Linux-Media Archive on lore.kernel.org
 help / color / Atom feed
From: 'Christoph Hellwig' <hch@lst.de>
To: David Laight <David.Laight@ACULAB.COM>
Cc: 'Christoph Hellwig' <hch@lst.de>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <maxime.ripard@bootlin.com>,
	Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
	Daniel Vetter <daniel@ffwll.ch>,
	Jani Nikula <jani.nikula@linux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	Ian Abbott <abbotti@mev.co.uk>,
	H Hartley Sweeten <hsweeten@visionengravers.com>,
	Intel Linux Wireless <linuxwifi@intel.com>,
	"moderated list:ARM PORT" <linux-arm-kernel@lists.infradead.org>,
	"dri-devel@lists.freedesktop.org"
	<dri-devel@lists.freedesktop.org>,
	"intel-gfx@lists.freedesktop.org"
	<intel-gfx@lists.freedesktop.org>,
	"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
	"linux-media@vger.kernel.org" <linux-media@vger.kernel.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	"linux-s390@vger.kernel.org" <linux-s390@vger.kernel.org>,
	"devel@driverdev.osuosl.org" <devel@driverdev.osuosl.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"iommu@lists.linux-foundation.org"
	<iommu@lists.linux-foundation.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 16/16] dma-mapping: use exact allocation in dma_alloc_contiguous
Date: Fri, 14 Jun 2019 17:05:58 +0200
Message-ID: <20190614150558.GA9402@lst.de> (raw)
In-Reply-To: <d93fd4c2c1584d92a05dd641929f6d63@AcuMS.aculab.com>

On Fri, Jun 14, 2019 at 03:01:22PM +0000, David Laight wrote:
> I'm pretty sure there is a lot of code out there that makes that assumption.
> Without it many drivers will have to allocate almost double the
> amount of memory they actually need in order to get the required alignment.
> So instead of saving memory you'll actually make more be used.

That code would already be broken on a lot of Linux platforms.

  reply index

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-14 13:47 use exact allocation for dma coherent memory Christoph Hellwig
2019-06-14 13:47 ` [PATCH 01/16] media: videobuf-dma-contig: use dma_mmap_coherent Christoph Hellwig
2019-06-14 13:47 ` [PATCH 02/16] drm/ati_pcigart: stop using drm_pci_alloc Christoph Hellwig
2019-06-14 13:47 ` [PATCH 03/16] drm/i915: " Christoph Hellwig
2019-06-14 16:45   ` [Intel-gfx] " Ville Syrjälä
2019-06-14 13:47 ` [PATCH 04/16] drm: move drm_pci_{alloc,free} to drm_legacy Christoph Hellwig
2019-06-14 13:47 ` [PATCH 05/16] drm: don't mark pages returned from drm_pci_alloc reserved Christoph Hellwig
2019-06-14 13:47 ` [PATCH 06/16] drm: don't pass __GFP_COMP to dma_alloc_coherent in drm_pci_alloc Christoph Hellwig
2019-06-14 13:47 ` [PATCH 07/16] IB/hfi1: stop passing bogus gfp flags arguments to dma_alloc_coherent Christoph Hellwig
2019-06-14 13:47 ` [PATCH 08/16] IB/qib: " Christoph Hellwig
2019-06-14 13:47 ` [PATCH 09/16] cnic: " Christoph Hellwig
2019-06-14 13:47 ` [PATCH 10/16] iwlwifi: " Christoph Hellwig
2019-06-14 13:47 ` [PATCH 11/16] s390/ism: " Christoph Hellwig
2019-06-14 13:47 ` [PATCH 12/16] staging/comedi: mark as broken Christoph Hellwig
2019-06-14 14:02   ` Greg KH
2019-06-14 14:48     ` Christoph Hellwig
2019-06-14 15:30       ` Greg KH
2019-06-14 15:34         ` Christoph Hellwig
2019-06-17 13:15           ` Ian Abbott
2019-06-14 13:47 ` [PATCH 13/16] mm: rename alloc_pages_exact_nid to alloc_pages_exact_node Christoph Hellwig
2019-06-14 13:47 ` [PATCH 14/16] mm: use alloc_pages_exact_node to implement alloc_pages_exact Christoph Hellwig
2019-06-14 13:47 ` [PATCH 15/16] dma-mapping: clear __GFP_COMP in dma_alloc_attrs Christoph Hellwig
2019-06-14 13:47 ` [PATCH 16/16] dma-mapping: use exact allocation in dma_alloc_contiguous Christoph Hellwig
2019-06-14 14:15   ` David Laight
2019-06-14 14:50     ` Christoph Hellwig
2019-06-14 15:01       ` David Laight
2019-06-14 15:05         ` Christoph Hellwig [this message]
2019-06-14 15:05       ` Robin Murphy
2019-06-14 15:08         ` Christoph Hellwig
2019-06-14 15:16         ` David Laight
2019-06-17  8:21 ` use exact allocation for dma coherent memory Dan Carpenter
2019-06-17  8:33   ` Christoph Hellwig
2019-06-19 16:29     ` Jason Gunthorpe
2019-06-20 10:51       ` Christoph Hellwig

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190614150558.GA9402@lst.de \
    --to=hch@lst.de \
    --cc=David.Laight@ACULAB.COM \
    --cc=abbotti@mev.co.uk \
    --cc=airlied@linux.ie \
    --cc=daniel@ffwll.ch \
    --cc=devel@driverdev.osuosl.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=hsweeten@visionengravers.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jani.nikula@linux.intel.com \
    --cc=joonas.lahtinen@linux.intel.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-rdma@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=linuxwifi@intel.com \
    --cc=maarten.lankhorst@linux.intel.com \
    --cc=maxime.ripard@bootlin.com \
    --cc=netdev@vger.kernel.org \
    --cc=rodrigo.vivi@intel.com \
    --cc=sean@poorly.run \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Media Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-media/0 linux-media/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-media linux-media/ https://lore.kernel.org/linux-media \
		linux-media@vger.kernel.org linux-media@archiver.kernel.org
	public-inbox-index linux-media


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-media


AGPL code for this site: git clone https://public-inbox.org/ public-inbox