From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: "Life is hard, and then you die" <ronald@innovation.ch>
Cc: Jonathan Corbet <corbet@lwn.net>,
"Rafael J. Wysocki" <rafael@kernel.org>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] debugfs: make return value of all debugfs helpers consistent
Date: Tue, 16 Apr 2019 15:29:25 +0200 [thread overview]
Message-ID: <20190416132925.GA17483@kroah.com> (raw)
In-Reply-To: <20190415232959.GC13033@innovation.ch>
On Mon, Apr 15, 2019 at 04:29:59PM -0700, Life is hard, and then you die wrote:
>
> Hi Greg,
>
> On Mon, Apr 15, 2019 at 10:48:44AM +0200, Greg Kroah-Hartman wrote:
> > On Mon, Apr 15, 2019 at 01:25:06AM -0700, Ronald Tschalär wrote:
> > > Since commit ff9fb72bc077 ("debugfs: return error values, not NULL")
> > > almost all the debugfs helpers have stopped returning NULL. The lone
> > > holdeout was debugfs_create_u32_array(). So fix that.
> > >
> > > Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
> > > ---
> > > fs/debugfs/file.c | 6 +++---
> > > 1 file changed, 3 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
> > > index ddd708b09fa1..bb706d073782 100644
> > > --- a/fs/debugfs/file.c
> > > +++ b/fs/debugfs/file.c
> > > @@ -999,8 +999,8 @@ static const struct file_operations u32_array_fops = {
> > > * Once array is created its size can not be changed.
> > > *
> > > * The function returns a pointer to dentry on success. If an error occurs,
> > > - * %ERR_PTR(-ERROR) or NULL will be returned. If debugfs is not enabled in
> > > - * the kernel, the value %ERR_PTR(-ENODEV) will be returned.
> > > + * %ERR_PTR(-ERROR) will be returned. If debugfs is not enabled in the kernel,
> > > + * the value %ERR_PTR(-ENODEV) will be returned.
> > > */
> > > struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
> > > struct dentry *parent,
> > > @@ -1009,7 +1009,7 @@ struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
> > > struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
> > >
> > > if (data == NULL)
> > > - return NULL;
> > > + return ERR_PTR(-ENOMEM);
> > >
> > > data->array = array;
> > > data->elements = elements;
> >
> > There is only one caller of this function in the kernel now, and it does
> > not even care about the return value at all, so we should just remove
> > the return value entirely as that's the easiest and best thing to do
> > here.
>
> Interesting argument: since this is a helper/library function, and
> therefore potentially used in the future by others, it seems to me
> that consistency with the other functions and providing error feedback
> would be important.
Not if you never actually use the return value for anything :)
> > I was going to start doing this slowly over time, but as you are
> > touching the function now, might as well do it here :)
>
> Are you saying the plan is to make all these helpers return void?
Yes, no caller should do anything "different" based on a return value of
a debugfs call. Note, sometimes you do want to save off dentries for
some files that you later remove, but that's it.
thanks,
greg k-h
next prev parent reply other threads:[~2019-04-16 14:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-15 8:25 [PATCH 0/2] debugfs helpers cleanups Ronald Tschalär
2019-04-15 8:25 ` [PATCH 1/2] debugfs: update documented return values of debugfs helpers Ronald Tschalär
2019-04-15 8:25 ` [PATCH 2/2] debugfs: make return value of all debugfs helpers consistent Ronald Tschalär
2019-04-15 8:48 ` Greg Kroah-Hartman
2019-04-15 23:29 ` Life is hard, and then you die
2019-04-16 13:29 ` Greg Kroah-Hartman [this message]
2019-04-16 13:46 ` [PATCH] debugfs: make debugfs_create_u32_array() return void Greg Kroah-Hartman
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=20190416132925.GA17483@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=corbet@lwn.net \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rafael@kernel.org \
--cc=ronald@innovation.ch \
/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).