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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Byungchul Park <byungchul.park@lge.com>,
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Subject: Re: [PATCH RFC v7 07/23] dept: Apply sdt_might_sleep_strong() to
 wait_for_completion()/complete()
In-Reply-To: <1673235231-30302-8-git-send-email-byungchul.park@lge.com>
References: <1673235231-30302-1-git-send-email-byungchul.park@lge.com>
 <1673235231-30302-8-git-send-email-byungchul.park@lge.com>
Date:   Wed, 18 Jan 2023 13:59:34 +0100
Message-ID: <87wn5khubt.ffs@tglx>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

On Mon, Jan 09 2023 at 12:33, Byungchul Park wrote:
> Makes Dept able to track dependencies by
> wait_for_completion()/complete().
>
> In order to obtain the meaningful caller points, replace all the
> wait_for_completion*() declarations with macros in the header.

That's just wrong.

> -extern void wait_for_completion(struct completion *);
> +extern void raw_wait_for_completion(struct completion *);

> +#define wait_for_completion(x)					\
> +({								\
> +	sdt_might_sleep_strong(NULL);				\
> +	raw_wait_for_completion(x);				\
> +	sdt_might_sleep_finish();				\
> +})

The very same can be achieved with a proper annotation which does not
enforce THIS_IP but allows to use __builtin_return_address($N). That's
what everything else uses too.

Thanks,

        tglx