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Message-ID: <c94bd56f8be79670542af53eaaf4bd749505b78b.camel@perches.com>
Subject: Re: [RFC PATCH v3 03/13] module: Move livepatch support to a
 separate file
From:   Joe Perches <joe@perches.com>
To:     Aaron Tomlin <atomlin@redhat.com>, mcgrof@kernel.org
Cc:     cl@linux.com, pmladek@suse.com, mbenes@suse.cz,
        akpm@linux-foundation.org, jeyu@kernel.org,
        linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org,
        live-patching@vger.kernel.org, atomlin@atomlin.com,
        ghalat@redhat.com, allen.lkml@gmail.com
Date:   Fri, 28 Jan 2022 23:27:29 -0800
In-Reply-To: <20220128203934.600247-4-atomlin@redhat.com>
References: <20220128203934.600247-1-atomlin@redhat.com>
         <20220128203934.600247-4-atomlin@redhat.com>
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On Fri, 2022-01-28 at 20:39 +0000, Aaron Tomlin wrote:
> No functional change.
> 
> This patch migrates livepatch support (i.e. used during module
> add/or load and remove/or deletion) from core module code into
> kernel/module/livepatch.c. At the moment it contains code to
> persist Elf information about a given livepatch module, only.
[]
> diff --git a/include/linux/module.h b/include/linux/module.h
[]
> @@ -668,11 +668,22 @@ static inline bool is_livepatch_module(struct module *mod)
>  {
>  	return mod->klp;
>  }
> +
> +static inline bool set_livepatch_module(struct module *mod)
> +{
> +	mod->klp = true;
> +	return true;
> +}
>  #else /* !CONFIG_LIVEPATCH */
>  static inline bool is_livepatch_module(struct module *mod)
>  {
>  	return false;
>  }
> +
> +static inline bool set_livepatch_module(struct module *mod)
> +{
> +	return false;
> +}
>  #endif /* CONFIG_LIVEPATCH */

style trivia:

Generally, these static inlines can be written deduplicating
the function declaration and using IS_ENABLED or #if inside
the definition.

Something like:

static inline bool is_livepatch_module(struct module *mod)
{
	if (IS_ENABLED(CONFIG_LIVEPATCH)) {
		mod->klp = true;
		return true;
	}
	return false;
}

or

static inline bool is_livepatch_module(struct module *mod)
{
#ifdef CONFIG_LIVEPATCH
	mod->klp = true;
	return true;
#else
	return false;
#endif
}