From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S933780AbcFQQMD (ORCPT <rfc822;w@1wt.eu>);
	Fri, 17 Jun 2016 12:12:03 -0400
Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:63446
	"EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK)
	by vger.kernel.org with ESMTP id S932106AbcFQQMA (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 17 Jun 2016 12:12:00 -0400
X-IronPort-AV: E=Sophos;i="5.26,484,1459807200"; 
   d="scan'208";a="181648367"
Date: Fri, 17 Jun 2016 18:11:53 +0200 (CEST)
From: Julia Lawall <julia.lawall@lip6.fr>
X-X-Sender: jll@hadrien
To: SF Markus Elfring <elfring@users.sourceforge.net>
cc: cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Christian Lamparter <chunkeey@googlemail.com>,
        David Woodhouse <dwmw2@infradead.org>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Hauke Mehrtens <hauke@hauke-m.de>, Jiri Slaby <jslaby@suse.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        Josh Boyer <jwboyer@fedoraproject.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Mark Brown <broonie@kernel.org>, Michal Marek <mmarek@suse.com>,
        Mimi Zohar <zohar@linux.vnet.ibm.com>,
        Ming Lei <ming.lei@canonical.com>,
        Stephen Boyd <stephen.boyd@linaro.org>, Takashi Iwai <tiwai@suse.de>,
        Vikram Mulukutla <markivx@codeaurora.org>
Subject: Re: [Cocci] [PATCH v2 4/8] scripts: add glimpse.sh for indexing the
 kernel
In-Reply-To: <477f1f1d-f60f-79b9-1f0f-f9cb030c240a@users.sourceforge.net>
Message-ID: <alpine.DEB.2.10.1606171809150.3164@hadrien>
References: <1466116292-21843-1-git-send-email-mcgrof@kernel.org> <1466116292-21843-5-git-send-email-mcgrof@kernel.org> <alpine.DEB.2.10.1606171129200.3164@hadrien> <477f1f1d-f60f-79b9-1f0f-f9cb030c240a@users.sourceforge.net>
User-Agent: Alpine 2.10 (DEB 1266 2009-07-14)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

> Under which circumstances will the indexing efforts pay off?

Indexing is beneficial when a semantic patch uses in an essential way some
words that appear rarely in the code base.  For example, the following
semantic patch will only do something useful on code that contains xyz:

- x = kmalloc();
  ..
- x = xyz();

There is no need to parse the code, match the thousands of occurrences of
kmalloc, nor to do the tracing of execution paths implied by ... if the
code does not contain any call to xyz anyway.

julia