From: "Christian König" <christian.koenig@amd.com>
To: Kalesh Singh <kaleshsingh@google.com>
Cc: jannh@google.com, jeffv@google.com, keescook@chromium.org,
surenb@google.com, minchan@kernel.org, hridya@google.com,
kernel-team@android.com, Alexey Dobriyan <adobriyan@gmail.com>,
Jonathan Corbet <corbet@lwn.net>,
Sumit Semwal <sumit.semwal@linaro.org>,
Andrew Morton <akpm@linux-foundation.org>,
Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
Michal Hocko <mhocko@suse.com>,
Alexey Gladkov <gladkov.alexey@gmail.com>,
Anand K Mistry <amistry@google.com>, NeilBrown <neilb@suse.de>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Michel Lespinasse <walken@google.com>,
Bernd Edlinger <bernd.edlinger@hotmail.de>,
Andrei Vagin <avagin@gmail.com>,
Yafang Shao <laoar.shao@gmail.com>,
Christian Brauner <christian.brauner@ubuntu.com>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-doc@vger.kernel.org, linux-media@vger.kernel.org,
dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org
Subject: Re: [PATCH v3 2/2] dmabuf: Add dmabuf inode number to /proc/*/fdinfo
Date: Fri, 5 Feb 2021 08:56:36 +0100 [thread overview]
Message-ID: <df97ba85-2291-487a-8af0-84398f9e8188@amd.com> (raw)
In-Reply-To: <20210205022328.481524-2-kaleshsingh@google.com>
Am 05.02.21 um 03:23 schrieb Kalesh Singh:
> If a FD refers to a DMA buffer add the DMA buffer inode number to
> /proc/<pid>/fdinfo/<FD> and /proc/<pid>/task/<tid>/fdindo/<FD>.
>
> The dmabuf inode number allows userspace to uniquely identify the buffer
> and avoids a dependency on /proc/<pid>/fd/* when accounting per-process
> DMA buffer sizes.
BTW: Why do we make this DMA-buf specific? Couldn't we always print the
inode number for all fds?
Regards,
Christian.
>
> Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
> ---
> Changes in v3:
> - Add documentation in proc.rst
> Changes in v2:
> - Update patch description
>
> Documentation/filesystems/proc.rst | 17 +++++++++++++++++
> drivers/dma-buf/dma-buf.c | 1 +
> 2 files changed, 18 insertions(+)
>
> diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
> index 2fa69f710e2a..fdd38676f57f 100644
> --- a/Documentation/filesystems/proc.rst
> +++ b/Documentation/filesystems/proc.rst
> @@ -2031,6 +2031,23 @@ details]. 'it_value' is remaining time until the timer expiration.
> with TIMER_ABSTIME option which will be shown in 'settime flags', but 'it_value'
> still exhibits timer's remaining time.
>
> +DMA Buffer files
> +~~~~~~~~~~~~~~~~
> +
> +::
> +
> + pos: 0
> + flags: 04002
> + mnt_id: 9
> + dmabuf_inode_no: 63107
> + size: 32768
> + count: 2
> + exp_name: system-heap
> +
> +where 'dmabuf_inode_no' is the unique inode number of the DMA buffer file.
> +'size' is the size of the DMA buffer in bytes. 'count' is the file count of
> +the DMA buffer file. 'exp_name' is the name of the DMA buffer exporter.
> +
> 3.9 /proc/<pid>/map_files - Information about memory mapped files
> ---------------------------------------------------------------------
> This directory contains symbolic links which represent memory mapped files
> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> index 9ad6397aaa97..d869099ede83 100644
> --- a/drivers/dma-buf/dma-buf.c
> +++ b/drivers/dma-buf/dma-buf.c
> @@ -414,6 +414,7 @@ static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file)
> {
> struct dma_buf *dmabuf = file->private_data;
>
> + seq_printf(m, "dmabuf_inode_no:\t%lu\n", file_inode(file)->i_ino);
> seq_printf(m, "size:\t%zu\n", dmabuf->size);
> /* Don't count the temporary reference taken inside procfs seq_show */
> seq_printf(m, "count:\t%ld\n", file_count(dmabuf->file) - 1);
next prev parent reply other threads:[~2021-02-05 7:57 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-05 2:23 [PATCH v3 1/2] procfs: Allow reading fdinfo with PTRACE_MODE_READ Kalesh Singh
2021-02-05 2:23 ` [PATCH v3 2/2] dmabuf: Add dmabuf inode number to /proc/*/fdinfo Kalesh Singh
2021-02-05 2:36 ` Randy Dunlap
2021-02-05 7:56 ` Christian König [this message]
2021-02-05 15:13 ` Kalesh Singh
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=df97ba85-2291-487a-8af0-84398f9e8188@amd.com \
--to=christian.koenig@amd.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=amistry@google.com \
--cc=avagin@gmail.com \
--cc=bernd.edlinger@hotmail.de \
--cc=christian.brauner@ubuntu.com \
--cc=corbet@lwn.net \
--cc=dri-devel@lists.freedesktop.org \
--cc=ebiederm@xmission.com \
--cc=gladkov.alexey@gmail.com \
--cc=hridya@google.com \
--cc=jannh@google.com \
--cc=jeffv@google.com \
--cc=kaleshsingh@google.com \
--cc=keescook@chromium.org \
--cc=kernel-team@android.com \
--cc=laoar.shao@gmail.com \
--cc=linaro-mm-sig@lists.linaro.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=mchehab+huawei@kernel.org \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
--cc=neilb@suse.de \
--cc=sumit.semwal@linaro.org \
--cc=surenb@google.com \
--cc=walken@google.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).