From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail2-relais-roc.national.inria.fr (mail2-relais-roc.national.inria.fr [192.134.164.83]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 34E7D3224; Sat, 18 Mar 2023 17:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=inria.fr; s=dc; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=t/EnRKvaSnN9nj3FCPFC2n3uFwpintvP56OIP4eUTpc=; b=vmKmoiSAsEE7+29gvZm9kauac+0MnkZONYLN5iMTnArlATVW1DevI2S/ wVODkWnxwZxXhxMEGx7meeRjxEcGYCx3Ie16PE0LcfaFG0kpYTYtHmkix vC/rkOfL3LNsTfdKa0h3D8pYx8eXkwEA4ZPTwPI8KNnjuGbJ+LDPBk5BA s=; Authentication-Results: mail2-relais-roc.national.inria.fr; dkim=none (message not signed) header.i=none; spf=SoftFail smtp.mailfrom=julia.lawall@inria.fr; dmarc=fail (p=none dis=none) d=inria.fr X-IronPort-AV: E=Sophos;i="5.98,271,1673910000"; d="scan'208";a="97891427" Received: from 231.85.89.92.rev.sfr.net (HELO hadrien) ([92.89.85.231]) by mail2-relais-roc.national.inria.fr with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Mar 2023 18:14:50 +0100 Date: Sat, 18 Mar 2023 18:14:50 +0100 (CET) From: Julia Lawall X-X-Sender: jll@hadrien To: Sumitra Sharma cc: Marc Dietrich , Greg Kroah-Hartman , ac100@lists.launchpad.net, linux-tegra@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, outreachy@lists.linux.dev Subject: Re: [PATCH] Staging: nvec: Change container_of macro to an inline function. In-Reply-To: <20230318170514.GA49181@sumitra.com> Message-ID: References: <20230318170514.GA49181@sumitra.com> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII On Sat, 18 Mar 2023, Sumitra Sharma wrote: > The macro has the drawback that one cannot determine > what type it applies to by looking at the definition. > Hence this macro definition is not type-safe. > > The inline function gives the same benefits as the > macro and only accepts the specific type of arguments. > Use static because the definition only requires it to be > visible in the current file. Sumitra, The subject line and log message could be a little less generic. For the subject line, one has the impression that you are changing the definition of container_of itself. The log message is also a bit wordy. Something like the following would be more concise and still present the issue: Convert to_nvec_led from a macro to an inline function, to make the relevant types apparent in the definition and to benefit from the type checking performed by the compiler at call sites. julia > > Signed-off-by: Sumitra Sharma > --- > drivers/staging/nvec/nvec_paz00.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/nvec/nvec_paz00.c b/drivers/staging/nvec/nvec_paz00.c > index 8b4da95081c8..9573ba762cdd 100644 > --- a/drivers/staging/nvec/nvec_paz00.c > +++ b/drivers/staging/nvec/nvec_paz00.c > @@ -14,8 +14,10 @@ > #include > #include "nvec.h" > > -#define to_nvec_led(led_cdev) \ > - container_of(led_cdev, struct nvec_led, cdev) > +static inline struct nvec_led *to_nvec_led(struct led_classdev *led_cdev) > +{ > + return container_of(led_cdev, struct nvec_led, cdev); > +} > > #define NVEC_LED_REQ {'\x0d', '\x10', '\x45', '\x10', '\x00'} > > -- > 2.25.1 > > >