Received-SPF: pass (google.com: domain of linux-kernel+bounces-19755-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
Date: Mon, 8 Jan 2024 10:21:15 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Linux Trace Kernel
 <linux-trace-kernel@vger.kernel.org>, Masami Hiramatsu
 <mhiramat@kernel.org>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Andy Shevchenko <andy@kernel.org>, Tom Zanussi <zanussi@kernel.org>
Subject: Re: [PATCH] tracing histograms: Simplify parse_actions() function
Message-ID: <20240108102115.43464fd6@gandalf.local.home>
In-Reply-To: <CAHp75VcsV8t2-6GB24Rz003B2JSAEOBjWD7B7FjEXuCQhkJ5pQ@mail.gmail.com>
References: <20240107203258.37e26d2b@gandalf.local.home>
	<CAHp75VcsV8t2-6GB24Rz003B2JSAEOBjWD7B7FjEXuCQhkJ5pQ@mail.gmail.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

On Mon, 8 Jan 2024 10:32:14 +0200
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Mon, Jan 8, 2024 at 3:31=E2=80=AFAM Steven Rostedt <rostedt@goodmis.or=
g> wrote:
> >
> > From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
> >
> > The parse_actions() function uses 'len =3D str_has_prefix()' to test wh=
ich
> > action is in the string being parsed. But then it goes and repeats the
> > logic for each different action. This logic can be simplified and
> > duplicate code can be removed as 'len' contains the length of the found
> > prefix which should be used for all actions. =20
>=20
> > Link: https://lore.kernel.org/all/20240107112044.6702cb66@gandalf.local=
.home/
> >
> > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> =20
>=20
> If you want Link to be formally a tag, you should drop the following
> blank line.

The link is for humans not for parsers.

>=20
>=20
> > +               if ((len =3D str_has_prefix(str, "onmatch(")))
> > +                       hid =3D HANDLER_ONMATCH;
> > +               else if ((len =3D str_has_prefix(str, "onmax(")))
> > +                       hid =3D HANDLER_ONMAX;
> > +               else if ((len =3D str_has_prefix(str, "onchange(")))
> > +                       hid =3D HANDLER_ONCHANGE; =20
>=20
> The repeating check for ( might be moved out as well after this like
>=20
>   if (str[len] !=3D '(') {
>     // not sure if you need data to be assigned here as well
>     ret =3D -EINVAL;
>     ...
>   }
>=20

Not sure how that makes it any better. It adds more code. I could start
with checking the "on" before checking for "match", "max" and "change", but
that just makes it more complex.

-- Steve