From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Jones Subject: Re: [PATCH RESUBMIT 1/2] fs/seq_file: Create new function seq_open_init() Date: Thu, 25 Sep 2014 10:10:05 +0100 Message-ID: <5423DBED.4090306@codethink.co.uk> References: <1411557356-10673-1-git-send-email-rob.jones@codethink.co.uk> <1411557356-10673-2-git-send-email-rob.jones@codethink.co.uk> <20140924143904.b6f12611013876253d8ac50a@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: rdunlap@infradead.org, viro@zeniv.linux.org.uk, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel@codethink.co.uk, keescook@chromium.org, penguin-kernel@I-love.SAKURA.ne.jp To: Andrew Morton Return-path: In-Reply-To: <20140924143904.b6f12611013876253d8ac50a@linux-foundation.org> Sender: linux-doc-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 24/09/14 22:39, Andrew Morton wrote: > On Wed, 24 Sep 2014 12:15:55 +0100 Rob Jones wrote: > >> Add a new function to help reduce boilerplate code. >> >> This is a wrapper function for seq_open() that will simplify the code in a >> significant number of cases where seq_open() is currently called. >> >> It's first use is in __seq_open_private(), thereby recovering most of >> the code space used by the new function. > > It would be nice to include one or more of the conversions in this patch > series so we can see what the effects look like. There are certainly lots of candidates around. However, I thought that the change to __seq_open_private() already gave a good illustration of the level of savings to be made, in that it more or less made the new function "self financing". > >> --- a/fs/seq_file.c >> +++ b/fs/seq_file.c >> @@ -639,28 +639,38 @@ int seq_release_private(struct inode *inode, struct file *file) >> } >> EXPORT_SYMBOL(seq_release_private); >> >> +int seq_open_init(struct file *f, const struct seq_operations *ops, void *p) >> +{ >> + struct seq_file *s; >> + int rc; >> + >> + rc = seq_open(f, ops); >> + if (rc) >> + return rc; >> + >> + s = f->private_data; >> + s->private = p; >> + >> + return 0; >> +} >> +EXPORT_SYMBOL(seq_open_init); > > A global exported-to-modules interface should be documented, please. > Especially when it has a void* argument. seq_file.c is patchy - some > of it is documented, some of it uses the read-programmers-mind > approach. I have included documentation as the second patch. Would it have been better to include them in a single patch? I didn't do that because seq_file and Documentation have different maintainers. I'm still learning the protocols here. > > > __seq_open_private() has > void *private; > > single_open() has > void *data > > And now seq_open_init() has > void *p > > but these all refer to the same thing. Can we have a bit of > consistency in the naming please? I suggest "private", to match > the seq_file field. A valid point and I can easily make the change but fixing single_open() would mean that the patch is addressing two issues, is that acceptable? Another protocol question, sorry. -- Rob Jones Codethink Ltd mailto:rob.jones@codethink.co.uk tel:+44 161 236 5575