linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Lukas Wunner <lukas@wunner.de>
To: Ira Weiny <ira.weiny@intel.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>,
	linux-pci@vger.kernel.org,
	Gregory Price <gregory.price@memverge.com>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Alison Schofield <alison.schofield@intel.com>,
	Vishal Verma <vishal.l.verma@intel.com>,
	Dave Jiang <dave.jiang@intel.com>,
	"Li, Ming" <ming4.li@intel.com>, Hillf Danton <hdanton@sina.com>,
	Ben Widawsky <bwidawsk@kernel.org>,
	linuxarm@huawei.com, linux-cxl@vger.kernel.org
Subject: Re: [PATCH v3 16/16] cxl/pci: Rightsize CDAT response allocation
Date: Thu, 16 Feb 2023 09:03:43 +0100	[thread overview]
Message-ID: <20230216080343.GA23125@wunner.de> (raw)
In-Reply-To: <63ed7f50ed22b_19cbb72946d@iweiny-mobl.notmuch>

On Wed, Feb 15, 2023 at 04:56:48PM -0800, Ira Weiny wrote:
> Lukas Wunner wrote:
> > Jonathan notes that cxl_cdat_get_length() and cxl_cdat_read_table()
> > allocate 32 dwords for the DOE response even though it may be smaller.
> > 
> > In the case of cxl_cdat_get_length(), only the second dword of the
> > response is of interest (it contains the length).  So reduce the
> > allocation to 2 dwords and let DOE discard the remainder.
> > 
> > In the case of cxl_cdat_read_table(), a correctly sized allocation for
> > the full CDAT already exists.  Let DOE write each table entry directly
> > into that allocation.  There's a snag in that the table entry is
> > preceded by a Table Access Response Header (1 dword).
> 
> Where is this 'Table Access Response Header' defined?

CXL r3.0 table 8-14 (sec 8.1.11.1, page 399).

I'll amend the commit message with a reference to the spec.

Thanks,

Lukas

  reply	other threads:[~2023-02-16  8:03 UTC|newest]

Thread overview: 62+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-10 20:25 [PATCH v3 00/16] Collection of DOE material Lukas Wunner
2023-02-10 20:25 ` [PATCH v3 01/16] cxl/pci: Fix CDAT retrieval on big endian Lukas Wunner
2023-02-11  0:22   ` Dan Williams
2023-02-19 13:03     ` Lukas Wunner
2023-02-14 11:15   ` Jonathan Cameron
2023-02-14 13:51     ` Lukas Wunner
2023-02-14 15:45       ` Jonathan Cameron
2023-02-28  2:53   ` Alexey Kardashevskiy
2023-02-28  8:24     ` Lukas Wunner
2023-02-28 12:08       ` Alexey Kardashevskiy
2023-02-10 20:25 ` [PATCH v3 02/16] cxl/pci: Handle truncated CDAT header Lukas Wunner
2023-02-11  0:40   ` Dan Williams
2023-02-11  9:34     ` Lukas Wunner
2023-02-14 11:16   ` Jonathan Cameron
2023-02-15  1:41   ` Li, Ming
2023-02-10 20:25 ` [PATCH v3 03/16] cxl/pci: Handle truncated CDAT entries Lukas Wunner
2023-02-11  0:50   ` Dan Williams
2023-02-11 10:56     ` Lukas Wunner
2023-02-14 11:30   ` Jonathan Cameron
2023-02-10 20:25 ` [PATCH v3 04/16] cxl/pci: Handle excessive CDAT length Lukas Wunner
2023-02-11  1:04   ` Dan Williams
2023-02-14 11:33   ` Jonathan Cameron
2023-02-16 10:26     ` Lukas Wunner
2023-02-17 10:01       ` Jonathan Cameron
2023-02-10 20:25 ` [PATCH v3 05/16] PCI/DOE: Silence WARN splat with CONFIG_DEBUG_OBJECTS=y Lukas Wunner
2023-02-10 20:25 ` [PATCH v3 06/16] PCI/DOE: Fix memory leak " Lukas Wunner
2023-02-11  1:06   ` Dan Williams
2023-03-01  1:51   ` Davidlohr Bueso
2023-02-10 20:25 ` [PATCH v3 07/16] PCI/DOE: Provide synchronous API and use it internally Lukas Wunner
2023-02-15  1:45   ` Li, Ming
2023-02-28 18:58   ` Davidlohr Bueso
2023-02-10 20:25 ` [PATCH v3 08/16] cxl/pci: Use synchronous API for DOE Lukas Wunner
2023-02-10 20:25 ` [PATCH v3 09/16] PCI/DOE: Make asynchronous API private Lukas Wunner
2023-02-15  1:48   ` Li, Ming
2023-02-10 20:25 ` [PATCH v3 10/16] PCI/DOE: Deduplicate mailbox flushing Lukas Wunner
2023-02-14 11:36   ` Jonathan Cameron
2023-02-15  5:07   ` Li, Ming
2023-02-10 20:25 ` [PATCH v3 11/16] PCI/DOE: Allow mailbox creation without devres management Lukas Wunner
2023-02-14 11:51   ` Jonathan Cameron
2023-02-15  5:17   ` Li, Ming
2023-02-10 20:25 ` [PATCH v3 12/16] PCI/DOE: Create mailboxes on device enumeration Lukas Wunner
2023-02-15  2:07   ` Li, Ming
2023-02-28  1:18   ` Alexey Kardashevskiy
2023-02-28  1:39     ` Dan Williams
2023-02-28  5:43     ` Lukas Wunner
2023-02-28  7:24       ` Alexey Kardashevskiy
2023-02-28 10:42         ` Jonathan Cameron
2023-03-02 20:22         ` Lukas Wunner
2023-03-07  1:55           ` Alexey Kardashevskiy
2023-04-03  0:55           ` Alexey Kardashevskiy
2023-02-10 20:25 ` [PATCH v3 13/16] cxl/pci: Use CDAT DOE mailbox created by PCI core Lukas Wunner
2023-02-10 20:25 ` [PATCH v3 14/16] PCI/DOE: Make mailbox creation API private Lukas Wunner
2023-02-15  2:13   ` Li, Ming
2023-02-10 20:25 ` [PATCH v3 15/16] PCI/DOE: Relax restrictions on request and response size Lukas Wunner
2023-02-15  5:05   ` Li, Ming
2023-02-15 11:49     ` Lukas Wunner
2023-02-10 20:25 ` [PATCH v3 16/16] cxl/pci: Rightsize CDAT response allocation Lukas Wunner
2023-02-14 13:05   ` Jonathan Cameron
2023-02-16  0:56   ` Ira Weiny
2023-02-16  8:03     ` Lukas Wunner [this message]
2023-02-28  1:45   ` Alexey Kardashevskiy
2023-02-28  5:55     ` Lukas Wunner

Reply instructions:

You may reply publicly 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=20230216080343.GA23125@wunner.de \
    --to=lukas@wunner.de \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=alison.schofield@intel.com \
    --cc=bwidawsk@kernel.org \
    --cc=dan.j.williams@intel.com \
    --cc=dave.jiang@intel.com \
    --cc=gregory.price@memverge.com \
    --cc=hdanton@sina.com \
    --cc=helgaas@kernel.org \
    --cc=ira.weiny@intel.com \
    --cc=linux-cxl@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linuxarm@huawei.com \
    --cc=ming4.li@intel.com \
    --cc=vishal.l.verma@intel.com \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).