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Message-ID: <1416270932.29010.6.camel@perches.com>
Subject: Re: [PATCH 20/26 v5] seq_buf: Add seq_buf_can_fit() helper function
From: Joe Perches <joe@perches.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jiri Kosina <jkosina@suse.cz>, Petr Mladek <pmladek@suse.cz>
Date: Mon, 17 Nov 2014 16:35:32 -0800
In-Reply-To: <20141117192733.0ab1ba2e@gandalf.local.home>
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On Mon, 2014-11-17 at 19:27 -0500, Steven Rostedt wrote:
> On Mon, 17 Nov 2014 16:07:33 -0800
> Joe Perches <joe@perches.com> wrote:
> 
> > On Mon, 2014-11-17 at 12:36 -0500, Steven Rostedt wrote:
> > > On Fri, 14 Nov 2014 23:59:07 -0500
> > > Steven Rostedt <rostedt@goodmis.org> wrote:
> > > 
> > > > From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
> > > > 
> > > > Add a seq_buf_can_fit() helper function that removes the possible mistakes
> > > > of comparing the seq_buf length plus added data compared to the size of
> > > > the buffer.
> > []
> > > > +static bool seq_buf_can_fit(struct seq_buf *s, size_t len)
> > > > +{
> > > > +	return s->len + len < s->size;
> > > > +}
> > > > +
> > 
> > Why is this useful?
> 
> Places the logic in one place and makes the next patch much shorter.

What "logic" does it place in one place and
how does it matter?

I don't see it making mistakes more or less
likely, I just see it being used to avoid
setting the overflow state which seems like
more of an error than anything else.

Why avoid setting overflow at all?