From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77B1FC6379F for ; Fri, 20 Nov 2020 11:57:36 +0000 (UTC) Received: from isis.lip6.fr (isis.lip6.fr [132.227.60.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6F5D122253 for ; Fri, 20 Nov 2020 11:57:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6F5D122253 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=inria.fr Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=cocci-bounces@systeme.lip6.fr Received: from systeme.lip6.fr (systeme.lip6.fr [132.227.104.7]) by isis.lip6.fr (8.15.2/8.15.2) with ESMTP id 0AKBv6KL004013; Fri, 20 Nov 2020 12:57:06 +0100 (CET) Received: from systeme.lip6.fr (systeme.lip6.fr [127.0.0.1]) by systeme.lip6.fr (Postfix) with ESMTP id 92F587789; Fri, 20 Nov 2020 12:57:06 +0100 (CET) Received: from isis.lip6.fr (isis.lip6.fr [132.227.60.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by systeme.lip6.fr (Postfix) with ESMTPS id EE1AA7B6 for ; Fri, 20 Nov 2020 12:57:04 +0100 (CET) Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by isis.lip6.fr (8.15.2/8.15.2) with ESMTP id 0AKBv4lK007751 for ; Fri, 20 Nov 2020 12:57:04 +0100 (CET) X-IronPort-AV: E=Sophos;i="5.78,356,1599516000"; d="scan'208";a="365151898" Received: from 173.121.68.85.rev.sfr.net (HELO hadrien) ([85.68.121.173]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Nov 2020 12:57:03 +0100 Date: Fri, 20 Nov 2020 12:57:03 +0100 (CET) From: Julia Lawall X-X-Sender: jll@hadrien To: Alexandru Ardelean In-Reply-To: Message-ID: References: User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 X-Greylist: Sender IP whitelisted, Sender e-mail whitelisted, not delayed by milter-greylist-4.4.3 (isis.lip6.fr [132.227.60.2]); Fri, 20 Nov 2020 12:57:07 +0100 (CET) X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.4.3 (isis.lip6.fr [132.227.60.2]); Fri, 20 Nov 2020 12:57:04 +0100 (CET) X-Scanned-By: MIMEDefang 2.78 on 132.227.60.2 X-Scanned-By: MIMEDefang 2.78 on 132.227.60.2 Cc: LKML , Robo Bot , Andy Shevchenko , Joe Perches , Alexandru Ardelean , cocci Subject: Re: [Cocci] Proposal for a new checkpatch check; matching _set_drvdata() & _get_drvdata() X-BeenThere: cocci@systeme.lip6.fr X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: cocci-bounces@systeme.lip6.fr Errors-To: cocci-bounces@systeme.lip6.fr On Fri, 20 Nov 2020, Alexandru Ardelean wrote: > On Fri, Nov 20, 2020 at 12:47 PM Julia Lawall wrote: > > > > > > > > On Thu, 19 Nov 2020, Joe Perches wrote: > > > > > On Thu, 2020-11-19 at 17:16 +0200, Andy Shevchenko wrote: > > > > On Thu, Nov 19, 2020 at 4:09 PM Alexandru Ardelean > > > > wrote: > > > > > > > > > > Hey, > > > > > > > > > > So, I stumbled on a new check that could be added to checkpatch. > > > > > Since it's in Perl, I'm reluctant to try it. > > > > > > > > > > Seems many drivers got to a point where they now call (let's say) > > > > > spi_set_drvdata(), but never access that information via > > > > > spi_get_drvdata(). > > > > > Reasons for this seem to be: > > > > > 1. They got converted to device-managed functions and there is no > > > > > longer a remove hook to require the _get_drvdata() access > > > > > 2. They look like they were copied from a driver that had a > > > > > _set_drvdata() and when the code got finalized, the _set_drvdata() was > > > > > omitted > > > > > > > > > > There are a few false positives that I can notice at a quick look, > > > > > like the data being set via some xxx_set_drvdata() and retrieved via a > > > > > dev_get_drvdata(). > > > > > > > > I can say quite a few. And this makes a difference. > > > > So, basically all drivers that are using PM callbacks would rather use > > > > dev_get_drvdata() rather than bus specific. > > > > > > > > > I think checkpatch reporting these as well would be acceptable simply > > > > > from a reviewability perspective. > > > > > > > > > > I did a shell script to quickly check these. See below. > > > > > It's pretty badly written but it is enough for me to gather a list. > > > > > And I wrote it in 5 minutes :P > > > > > I initially noticed this in some IIO drivers, and then I suspected > > > > > that this may be more widespread. > > > > > > > > It seems more suitable for coccinelle. > > > > > > To me as well. > > > > To me as well, since it seems to involve nonlocal information. > > > > I'm not sure to understand the original shell script. Is there > > something interesting about pci_set_drvdata? > > Ah, it's a stupid script I wrote in 5 minutes, so I did not bother to > make things smart. > In the text-matching I did in shell, there are some entries that come > from comments and docs. > It's only about 3-4 entries, so I just did a visual/manual ignore. > > In essence: > The script searches for all strings that contain _set_drvdata. > The separators are whitespace. > It creates a list of all xxxx_set_drvdata functions. > For each xxxx_set_drvdata function: > It checks all files that have a xxxx_set_drvdata entry, but no > xxxx_get_drvdata OK, but I have the impression that you want to ignore pci_set_drvdata for some reason? Or did I misunderstand? julia > > I piped this output into a file and started manually checking the drivers. > There is one [I forget which function] that is xxxx_set_drvdata() but > equivalent is xxxx_drvdata() > > As Andy said, some precautions must be taken in places where > xxxx_set_drvdata() is called but dev_get_drvdata() is used. > Cases like PM suspend/resume calls. > And there may be some cases outside this context. > > > > > > julia > _______________________________________________ Cocci mailing list Cocci@systeme.lip6.fr https://systeme.lip6.fr/mailman/listinfo/cocci